Class / Patent application number | Description | Number of patent applications / Date published |
318400330 | Voltage injection detection (e.g., voltage injected at startup to determine position, etc.) | 72 |
20090085505 | Electric drive unit - Electric drive units comprising a common active part having a stator and a rotor, which has windings and/or permanent magnets for a drive function and an energy transmission function, enable the rotor winding that is provided for energy transmission to be used to allow position detection at a low additional cost. For this purpose, a power converter in the rotor, which provides the output of electrical energy for the energy transmission function, impresses an alternating voltage into the rotor winding, said voltage being detected in the stator and allowing the rotor position to be determined. | 04-02-2009 |
20090096396 | Method for Determining the Rotor Position of a Separately Excited Rotating Electrical Machine - A method is specified for determining the rotor position of a separately excited rotating electrical machine which machine has a stator winding set and a rotor winding set and in which method the stator winding set is fed from an associated converter unit, and the rotor winding set is fed from an associated exciter unit. First of all, the stator winding set is short-circuited by means of the converter unit. An exciter voltage signal is then applied to the rotor winding set by means of the exciter unit, which exciter voltage signal has a change from a variable first voltage value to a variable second voltage value: Furthermore, the stator current (Isa, Isb, Isc) is determined in each winding of the stator winding set, and a rotor position angle (θ) is calculated. | 04-16-2009 |
20090108783 | Rotor orientation detection in brushless DC motors - In order to determine the orientation of the rotor of a brushless DC motor | 04-30-2009 |
20090128074 | INITIAL ROTOR POSITION DETECTION AND START-UP SYSTEM FOR A DYNAMOELECTRIC MACHINE - A method for detecting an initial rotor angular position and starting a dynamoelectric machine having a stator and a rotor includes the steps of driving the dynamoelectric machine into partial magnetic saturation to determine the initial rotor angular position of the dynamoelectric machine, and starting the dynamoelectric machine utilizing the initial rotor angular position previously determined. | 05-21-2009 |
20090146597 | METHOD FOR DETECTING THE POSITION OF A ROTOR - The invention relates to a method for determining the position of a rotor ( | 06-11-2009 |
20090174355 | Starting Apparatus for a Direct Current Brushless Motor and Method Thereof - A starting apparatus for a direct current (DC) brushless motor and a method thereof are provided. The DC brushless motor comprises a plurality of windings presenting a joint connection via a common connection. The starting apparatus provides current to two of the three windings and rotates the DC brushless motor to obtain a Back Electro-Motive Force (BEMF) from the floating winding. Then, the starting apparatus provides a current to another two windings to operate the motor according to the variation of BEMF induced by the swing of the motor when it rotates to a static equilibrium point. | 07-09-2009 |
20090179603 | Control Apparatus for Starting a Direct Current Brushless Motor and Method Thereof - An apparatus for starting a direct current brushless motor and a method thereof are provided. The direct current brushless motor comprises a plurality of windings. The control apparatus comprises a sense amplifier, a differential circuit, and a control circuit. The sense amplifier is configured to detect a first back electromotive force of a non-electrified first winding. The differential circuit is configured to calculate a differential value of the first back electromotive force. The control circuit is configured to provide a current to two of the windings and to switch the current to another two of the windings to start the direct current brushless motor. | 07-16-2009 |
20090200974 | SENSORLESS CONTROL APPARATUS OF SYNCHRONOUS MACHINE - A sensorless control apparatus of a rotary machine includes an inverter | 08-13-2009 |
20090251089 | Systems and Methods for Detecting Angular Position - Methods and systems for detecting an angular position of an electric motor are disclosed, including sending an electrical pulse through a stator coil of the electric motor, determining an approximate angular position of a rotor of the electric motor in response to detecting an timing of a returning electrical pulse from the stator coil, the timing of the returning electrical pulse being indicative of the angular position of the rotor; and determining an accurate position of the rotor in response to sensing a transition of a digital sensor in response to the rotor rotating relative to the stator, the transition being indicative of the accurate position. | 10-08-2009 |
20090261765 | SYNCHRONOUS MOTOR, ENCODERLESS MOTOR SYSTEM AND A METHOD FOR OPERATING AN ENCODERLESS MOTOR SYSTEM WITH A SYNCHRONOUS MOTOR - The invention relates to a synchronous motor ( | 10-22-2009 |
20090278485 | Device and Method for Determining the Rotational Position of a Rotor in an Electric Machine - The invention relates to a device and a method for determining the rotational position of the rotor of an electric machine that has star-connected pole winding phases. The device is equipped with a unit for applying voltage pulses ( | 11-12-2009 |
20100026223 | METHOD AND APPARATUS FOR IDENTIFYING ORIENTATION OF A STATIONARY ROTOR IN A SENSOR-LESS PMSM - A method and apparatus for determining rotor position in a stationary rotor of a sensor-less permanent magnet synchronous machine that employs a rotating magnetic field to identify a magnetic axis of the stator without a magnetic direction and then determines magnetic direction by applying pulses along the magnet axis in two polarities. | 02-04-2010 |
20100045222 | DIRECT FLUX REGULATED PERMANENT MAGNET BRUSHLESS MOTOR UTILIZING SENSORLESS CONTROL BY DC AND AC EXCITATION - A flux regulated permanent magnet brushless motor has a stator having an inner peripheral bore. A permanent magnet rotor is mounted within the inner peripheral bore. A control winding is supplied to a DC current to regulate flux of the machine. A small AC current is also supplied and an output is sensed to determine a position of the permanent magnet rotor. | 02-25-2010 |
20100090631 | Sensorless Method and Related Device for Starting a Three-phase Brushless Direct-current Motor - A sensorless method for starting a three-phase brushless direct-current motor includes generating a start-up control signal, a start mode selection signal, and a control signal commutation period; switching to a start mode according to the start mode selection signal; implementing a position aligning procedure according to the start-up control signal and the control signal commutation period; detecting a zero crossing point of back electromotive forces during each control signal commutation period; outputting a sensorless mode selection signal while detecting the zero crossing points of the back electromotive forces during consecutive control signal commutation periods; switching to a sensorless mode according to the sensorless mode selection signal; and detecting a zero crossing point of back electromotive forces in the sensorless mode to determine a starting result of the three-phase brushless direct-current motor. | 04-15-2010 |
20100090632 | MOTOR MAGNETIC POLE POSITION DETECTING DEVICE - A motor magnetic pole position detecting device includes a detection current command generation unit generating a detection AC current command, a current detection section detecting a current flowing into the motor, a coordinate conversion unit vector-converting the current detected by the current detection section into an excitation component and a torque component both represented by a d-q orthogonal coordinate system based on a phase angle obtained at any rotational frequency, a current control unit delivering a voltage command to current-control the motor based on the detection current command and the current converted by the coordinate conversion unit, an inductance calculation unit calculating motor inductance based on the voltage command and the current converted by the coordinate conversion unit, and a magnetic pole position detection section calculating a frequency and phase of the inductance calculated by the inductance calculation unit, converting the inductance phase into a motor magnetic pole position. | 04-15-2010 |
20100097022 | LOCATION SYSTEM AND METHOD - A location system is configured for determining a magnetic pole position of a motor. The location system includes a motor driver, a current control module, a current feedback apparatus, a speed feedback apparatus, and a magnetic pole position location module. The current control module is configured for set current of the motor via the motor driver. The current feedback apparatus is configured for sensing an actual current of the motor. The speed feedback apparatus is configured for sensing an actual speed of the motor. The magnetic pole position location module is configured for inputting a magnetic pole position of the motor, receiving the actual current from the current feedback apparatus, receiving the actual speed from the speed feedback apparatus, and processing the actual current and the actual speed to obtain an initial magnetic pole position. | 04-22-2010 |
20100109589 | BRUSHLESS MOTOR, BRUSHLESS MOTOR CONTROL SYSTEM, AND BRUSHLESS MOTOR CONTROL METHOD - A brushless motor control system according to the present invention detects a rotor stop position when activating the brushless motor including a stator having coils of three phases U, V, and W, and controls a phase voltage for energizing the coils of the respective phases U, V, and W, and the brushless motor includes the stator having coils of phases U, V, and W of N (N≧2) poles, in which any one phase coil among the coils of the phases U, V, and W is removed in one of the N poles, and the brushless motor control system includes: a current rise detecting circuit that, when the brushless motor is in a stop state, sequentially selects coils of two phases from the coils of the respective phases U, V, and W, applies a predetermined direct current voltage between the selected coils of the two phases, and detects a value of an electric current flowing to the selected coils of the two phases; and a rotor stop position detecting unit that determines a rotor stop position of the brushless motor based on information of the value of the electric current flowing to the respective phase coils which is detected by the current rise detecting circuit. | 05-06-2010 |
20100141191 | SYSTEMS AND METHODS FOR DETERMINING A COMMUTATION STATE FOR A BRUSHLESS DC MOTOR - A system for determining a commutation state for a brushless DC motor includes flyback detection circuitry that detects a flyback condition for each of a plurality of motor commutation states for the multiphase motor. The flyback detection circuitry provides a detection signal indicative of the detected flyback condition for each of a plurality of motor commutation states for the substantially stationary multiphase motor. A timer provides a time value based on the detection signal, the time value indicating a duration for the flyback condition for each respective motor commutation state. Logic is determines the commutation state for the multiphase motor based on the time value for each of the plurality of motor commutation states. | 06-10-2010 |
20100141192 | OPERATION OF BLDC MOTORS - The present invention there is provides a method of determining the rotor position in an electric motor comprising the steps of: superimposing one or more alternating signals on to the driving waveform so as to generate one or more oscillating currents in the stator coils; monitoring the variation in magnitude of the oscillating currents and thereby determining the rotor position. Typically, two alternating signals are applied in opposition so as to have no net effect on the torque applied by the driving waveform. Using this technique rotor position estimation can be obtained at start-up from stand-still and at low to medium speeds. The method can be used in applications where a fast motor start is needed under unknown load conditions and can be used to detect when the rotor has passed a certain position that coincides with the commutation instance. | 06-10-2010 |
20100156333 | Motor control device and drive device for hybrid vehicle - A hybrid drive device includes a first motor; an operative mechanism that drivingly connects the first motor to an engine of a vehicle; a second motor that is drivingly connected to a drive wheel; an engine rotation speed sensor that detects a rotation speed of the engine; a magnetic pole position sensor that detects a magnetic pole position of the second motor; a current sensor that detects a current flowing to the first motor; a sensorless motor control device that estimates a magnetic pole position of the first motor based on the current detected by the current sensor, and drivingly controls the first motor; and a second motor control device that drivingly controls the second motor based on the magnetic pole position detected by the magnetic pole position sensor. | 06-24-2010 |
20100156334 | Sensorless motor control device - A sensorless motor control device includes a magnetic pole position estimating unit that does not use a sensor to detect a magnetic pole position of a motor having a salient rotor, and overlays a high-frequency current on the motor to estimate the magnetic pole position of the rotor of the motor; and a high-frequency current control unit for changing a magnitude of the high-frequency current based on a magnitude of one of a torque and a current of the motor. | 06-24-2010 |
20100171455 | INITIAL POLARITY DETECTION FOR PERMANENT MAGNET MOTOR DRIVES - Methods and apparatus are provided for aligning a control reference axis with a magnetic north of a permanent magnet motor. The method includes the steps of injecting a predetermined stator current on an estimated reference axis of the permanent magnet motor and introducing predetermined error on the estimated reference axis. The method further includes the steps of determining if a speed of the permanent magnet motor is greater than a predetermined threshold speed and setting the control reference axis to 180° added to the estimated reference axis if the speed of the permanent magnet motor is greater than the predetermined threshold speed or setting the control reference axis to the estimated reference axis if the speed of the permanent magnet motor is less than or equal to the predetermined threshold speed. | 07-08-2010 |
20100181952 | INITIAL ROTOR POSITION DETECTION FOR PERMANENT MAGNET SYNCHRONOUS MOTORS - An apparatus and method for use with a PMSM detect the fall time or the rise time and the fall time of a motor current in the PMSM under different voltage vectors when the PMSM is in start-up to determine an initial rotor position for the PMSM at standstill. | 07-22-2010 |
20100225262 | METHOD FOR DETERMINING A ROTOR POSITION IN A PERMANENT MAGNET MOTOR - A method for determining the position of a rotor in a permanent magnet synchronous motor includes applying voltage pulses to the windings at successive electrical angles while the motor is at a standstill. The resultant current is sampled. The position of a maximum current is determined by identifying an segment of an electrical cycles which includes the maximum current, and using a spline interpolation to model the current flow in this segment. The maximum current is then correlated to the position of the rotor. | 09-09-2010 |
20100277113 | Position Estimation At Starting and Lower Speeds in Three-Phase Switched Reluctance Machines - Provided is a method of indirect position estimation in three-phase switched reluctance machines. The method may comprise providing a three-phase switched reluctance machine. A three-phase switched reluctance machine may comprise a rotor and three phases. The method may further comprise producing data about the machine, setting threshold current values for at least a first phase; and sensing rotor position. Sensing rotor position may comprise applying a sensing pulse voltage sufficient to induce a pulse current having some maximum amperage in the first phase, determining the amplitude of the maximum amperage of said pulse current with respect to the thresholds for the first phase, and determining the sector of the rotor based upon the amplitude of the maximum amperage of the pulse current in the first phase. | 11-04-2010 |
20100301790 | ROTOR POSITION ESTIMATOR FOR AN ELECTRICAL MACHINE - A method for estimating a rotor position in an electrical machine is provided. The method is applicable to electrical machines that have magnetic saliency. The method includes extracting the rotor position from a demodulated output signal generated in response to an injected high frequency carrier signal and determining a position error compensation based upon a demodulation delay and a velocity or rotational frequency of the electrical machine. The method also includes estimating the rotor position by applying the position error compensation to the extracted rotor position. | 12-02-2010 |
20100327789 | SENSORLESS CONTROL OF SALIENT-POLE MACHINES - A controller ( | 12-30-2010 |
20110037421 | DETERMINATION OF THE POSITION OF THE ROTOR OF AN ELECTRIC MACHINE - The invention relates to a frequency converter, and also to a method for determining the position of the rotor of an electric machine. The frequency converter comprises a load bridge and also a control of the load bridge, for supplying electricity between the load bridge and an electric machine connected to the load bridge. The frequency converter comprises a determination for at least one electrical parameter of the aforementioned electric machine, and the frequency converter comprises a determination for the position of the rotor of the aforementioned electric machine. The load bridge is fitted to supply a first alternating electricity excitation signal, which is formed in relation to the electrical angle of the electric machine, to the aforementioned electric machine. The frequency converter is further fitted to determine the first alternating electricity response signal corresponding to the aforementioned first alternating electricity excitation signal, and the position of the rotor is determined on the basis of the first alternating electricity response signal. | 02-17-2011 |
20110089876 | FAIL-SAFE CONTROLS FOR ELECTRIC TRACTION DRIVE SYSTEMS - A method is provided for operation of an internal permanent magnet motor having a rotor. The method includes determining whether a neutral point access signal is received from the rotor and operating the internal permanent magnet motor using sensorless signals corresponding to a rotor position and a rotor speed of the rotor derived by a first sensorless signal estimation method when the neutral point access signal is received from the rotor, wherein the first sensorless signal estimation method utilizes the neutral point access signal to generate the rotor position and the rotor speed. The method further includes operating the internal permanent magnet motor using sensorless signals corresponding to a rotor position and a rotor speed of the rotor derived by a second sensorless signal estimation method when the neutral point access signal is not received from the rotor, wherein the second sensorless signal estimation method does not utilize the neutral point access signal to generate the rotor position and the rotor speed. | 04-21-2011 |
20110109255 | SYSTEM AND METHOD FOR DETERMINING THE START POSITION OF A MOTOR - A system and method for determining the start position of a motor. According to an embodiment, a voltage pulse signal may be generated across a pair of windings in a motor. A current response signal will be generated and based upon the position of the motor, the response signal will be greater in one pulse signal polarity as opposed to an opposite pulse signal polarity. The response signal may be compared for s specific duration of time or until a specific integration threshold has been reached. Further, the response signal may be converted into a digital signal such that a sigma-delta circuit may smooth out glitches more easily. In this manner, the position of the motor may be determined to within 60 electrical degrees during a startup. | 05-12-2011 |
20110181220 | SYNCHRONOUS MACHINE STARTING DEVICE - A synchronous machine starting device includes a power conversion unit for converting supplied power into AC power and supplying the AC power to an armature of a synchronous machine, an AC voltage detection unit for detecting AC voltage supplied to the armature of the synchronous machine, a rotor position detection unit for detecting a rotor position of the synchronous machine, based on the detected AC voltage, and a power conversion control unit for controlling the power conversion portion, based on the detected rotor position. The rotor position detection portion includes a level monitoring unit outputting a first position signal indicating a timing at which a level of AC voltage supplied to the armature of the synchronous machine reaches a prescribed value, based on the detected AC voltage, a feedback operation unit for calculating an error of an estimated phase based on the estimated phase indicating the rotor position and the detected AC voltage, calculating the estimated phase based on the calculated phase error, and outputting a second position signal indicating the calculated estimated phase, and a selector circuit receiving the first position signal or a position signal obtained based on the first position signal, and the second position signal, selecting one of the received two position signals, and outputting the selected signal to the power conversion control unit as a signal indicating the rotor position of the synchronous machine. | 07-28-2011 |
20110199031 | MOTOR CONTROLLER FOR DETERMINING A POSITION OF A ROTOR OF AN AC MOTOR, AC MOTOR SYSTEM, AND METHOD OF DETERMINING A POSITION OF A ROTOR OF AN AC MOTOR - A motor controller for determining a position of a rotor of an AC motor, the motor controller comprises a control input for receiving a control signal, an output for providing a power control signal for controlling power applied to a stator of the AC motor, and an input for receiving a feedback signal representative of the current in the stator. The control input and output are coupled by a reference path, and the input is coupled to the control input by a feedback path. A carrier signal injection element injects a high frequency carrier signal in the reference path at an injection node. The motor controller is arranged to generate the power control signal in dependence on the control signal, the feedback signal, and the high frequency carrier signal. A position determining element generates a position signal representing the position of the rotor in dependence on the feedback signal which includes a carrier signal component comprising rotor position information. The motor controller further comprises a filter block coupled between the control input and the injection node in the reference path for filtering signals in the reference path in a frequency range including the frequency of the high frequency carrier signal. | 08-18-2011 |
20110234135 | MOTOR CONTROL DEVICE - A motor control device that has a high-frequency component, and a DC bias component that has a magnitude which causes a motor to be magnetically saturated and take on a certain value over a predetermined period, and is positively and negatively symmetrical are impressed as an observation command on a d-axis current command. The polarity of the magnetic pole of a permanent magnet is identified based on a relationship of large and small magnitudes between a first amplitude, which is attained during a period during which a DC bias component takes on a positive certain value, among amplitudes of a high- frequency component contained in a d-axis response voltage computed based on a feedback current respondent to the observation command, and a second amplitude attained during a period during which the DC bias component takes on a negative certain value. | 09-29-2011 |
20110248659 | DETERMINING INITIAL ROTOR POSITION OF AN ALTERNATING CURRENT MOTOR - Determination of an estimated initial angular position of the rotor of an AC motor includes application of voltages corresponding to a high frequency reference signal vector to the stator windings of the motor and production of an estimated initial angular position of the rotor as a function of the resulting q-axis stator current component iq_HF, adjustment of transformation of signal vectors from stationary to rotating coordinates and vice versa using the estimated angular position, and production of an adjusted estimated angular position of the rotor as a function of the q-axis stator current component as adjusted. Determination of an initial estimated angular position of the rotor and production of an adjusted initial estimated angular position of the rotor is performed with the rotor at standstill and before initially applying voltage corresponding to the drive signal vector to the stator windings, and production of an initial value of a drive signal vector command in stationary coordinates uses the adjusted estimated angular position. Determination of an estimated angular position of the rotor after application of stator current may use a different method, such as a physical relative position sensor. | 10-13-2011 |
20110254491 | SYNCHRONOUS-MACHINE STARTING DEVICE - A synchronous-machine starting device includes an induction voltage operating unit ( | 10-20-2011 |
20110279073 | METHOD FOR OPERATING AN ELECTRONICALLY COMMUTATED ELECTRIC MOTOR AND APPARATUS THEREFOR - The invention relates to a method of controlling the run-up of an electronically commutated electric motor ( | 11-17-2011 |
20110298406 | SYNCHRONOUS MACHINE STARTING DEVICE - In a synchronous machine starting device, an AC voltage detection unit detects AC voltage supplied to an armature of a synchronous machine through an electric power line from a power conversion unit. The AC voltage detection unit has a first output end and a second output end isolated from the electric power line, transforms AC voltage supplied through the electric power line at a first ratio to output the transformed voltage from the first output end, and transforms AC voltage supplied through the electric power line at a second ratio and then limits the transformed voltage to a prescribed positive voltage value or lower and a prescribed negative voltage value or higher for output from the second output end. Then, a detected voltage selection unit selects one of the voltage received from the first output end and the voltage received from the second output end, and outputs the selected one to a rotor position detection unit. The rotor position detection unit detects a rotor position of the synchronous machine based on the voltage received from the detected voltage selection unit. A power conversion control unit controls the power conversion unit based on the detected rotor position. | 12-08-2011 |
20120038303 | Apparatus And Method For Sensorless Identification Of Rotating Electrical Equivalent Circuit Parameters Of A Three-Phase Asynchronous Motor - Identification of electrical equivalent circuit parameters ( | 02-16-2012 |
20120062160 | Permanent Magnet Motor with Stator-Based Saliency for Position Sensorless Drive - A permanent magnet motor for position sensorless drive operation provides a stator design that exhibits a saliency (machine asymmetric) functionally dependent on rotor position as caused by periodic magnetic saturation of stator structure. This saturation property is caused by rotor zigzag leakage flux from surface permanent magnets. The stator structure may be designed to further saturate from zigzag leakage flux to provide greatest spatial saliency in the quadrature phase for motor position sensorless position estimation. The position, velocity, and shaft torque can be extracted by measuring the phase current from the stator coil of permanent magnet motor. | 03-15-2012 |
20120062161 | ROTOR POSITION DETECTION AT STANDSTILL AND LOW SPEEDS USING A PMG TO OPERATE A WOUND FIELD SYNCHRONOUS MACHINE - A method of operating a WFSM in a motoring mode determines a relative position of a PMG rotor with respect to the WFSM rotor. A PMG is coupled to the WFSM via a coupling shaft. A relative difference between the WFSM rotor position and the PMG rotor position is determined based on carrier injection sensorless (“CIS”) stimulation signals. The relative difference between the PMG rotor and the WFSM main machine in conjunction with the PMG rotor position is used to determine the WFSM rotor position during motoring operation of the main machine. A stator of the WFSM main machine is energized to maintain operation of the WFSM in response to the detected main rotor position. | 03-15-2012 |
20120098474 | APPARATUS FOR DETECTING THE POSITION OF A ROTOR OF AN ELECTRIC MOTOR AND RELATED METHOD - An apparatus detects the position of a rotor of an electric motor having three phases and a plurality of windings. The apparatus includes circuitry configured to connect at least two of said windings between first and second reference voltages according to a first current path disconnect said at least two windings, and allow the current stored in said two windings to be discharged through a second current path. The apparatus comprises a measuring circuit configured to measure the time period between the starting instant of storing the current in the two windings and the final instant of discharging the two windings and a rotor detector configured to detect the rotor position based at least in part on the measured time period. | 04-26-2012 |
20120153883 | Method for Determining the Rotor Position of a Synchronous Machine Operated in Field-Oriented Manner - A method for determining the rotor position of a synchronous machine operated in field-oriented manner, which has an effective inductivity that is dependent on the rotor position,
| 06-21-2012 |
20120181963 | INITIAL POSITION DETECTION FOR A SENSORLESS, BRUSHLESS DC MOTOR - Because there is a desire to migrate to sensorless, brushless direct current (DC) motors in large scale applications (i.e., vehicles), there is a need to provide a control system for such motors in large scale applications. Here, a motor controller is provided that uses small voltage pulses to generate currents (which are sufficiently small so as to not commute the motor) through pairs of phases. Based on the rise times of these currents, the motor controller can determine the initial position by using a lookup table (LUT) without commuting the motor. | 07-19-2012 |
20120194113 | Apparatus and method of estimating inductance of permanent magnet synchronous motor - A method of estimating inductance of a permanent magnet synchronous motor (PMSM) includes injecting a signal having a frequency differing from an operating frequency of the PMSM into the PMSM during sensorless operation, sensing magnitudes of current responses to the injected signal, and estimating an inductance value at which the magnitude of the sensed current response is minimal to be an actual inductance value of the PMSM, thereby estimating inductance used in the PMSM regardless of position estimation error of the PMSM and thus more accurately and reliably estimating inductance of the PMSM. | 08-02-2012 |
20120206077 | APPARATUS FOR CALCULATING ROTATIONAL POSITION OF ROTARY MACHINE - In a system, a superimposing element sets a command value vector of a high-frequency voltage signal and superimposes the high-frequency voltage signal with the command value vector on an output voltage of an inverter. The high-frequency voltage signal has a frequency higher than an electrical angular frequency of a rotary machine. The command value vector is correlated with a measured high-frequency component value of a current signal flowing in the rotary machine. A calculating element calculates a rotational angle of the rotary machine based on the measured high-frequency component value of the current signal flowing in the rotary machine. A reducing element controls at least one of the inverter and a direct voltage power supply to reduce a difference due to the dead time between the command value vector and a vector of a high-frequency voltage signal to be actually superimposed on the output voltage of the inverter. | 08-16-2012 |
20120223665 | METHOD AND DEVICE FOR DETERMINING A ROTOR POSITION OF A SYNCHRONOUS MACHINE - The invention relates to a method for determining a rotor position of a two-phase synchronous machine ( | 09-06-2012 |
20120293101 | Starting Sensorless Brushless Direct-Current (BLDC) Motors Based on Current-Ripple Analysis - In one embodiment, a method includes measuring between two consecutive electrical commutations of a brushless direct-current (BLDC) motor a current through the BLDC motor. One or more pulse-width-modulation (PWM)-configurable signals are driving the BLDC motor. The method includes determining a waveform of the current through the BLDC motor; if the waveform of the current through the BLDC motor comprises a first type, then increasing a duty cycle of each of one or more of the PWM-configurable signals driving the BLDC motor; and, if the waveform of the current through the BLDC motor comprises a second type, then decreasing a time interval between electrical communications of the BLDC motor. | 11-22-2012 |
20130043817 | DRIVING APPARATUS AND STOP POSITION DETECTION METHOD - A driving apparatus including an inverter unit for energizing the coil by switching ON and OFF of the switching element, an energization pattern determination unit for selecting a plurality of energization patterns, each of which indicates a direction of a current that flows through the coil, one by one when driving of a motor is started, and energizing the coil by switching ON and OFF of the switching element based on a selected energization pattern at a duty ratio corresponding to a value of a maximum current capable of being supplied by the power supply apparatus, a current applied time measurement unit for measuring an energization time, which is a time until a value of the current flowing through the coil reaches a predetermined target current value for each energization pattern, and a rotor stop position estimation unit for estimating a position at which the rotor stops. | 02-21-2013 |
20130093375 | METHOD OF POSITION SENSORLESS CONTROL OF AN ELECTRICAL MACHINE - A position sensorless control methodology for electrical machines using high frequency flux vector signal injection in the estimated rotor flux rotational reference frame is provided. In one aspect, the estimated position error function is derived directly from the stator flux equation without any simplification. The method is applicable for electrical generator motoring mode operation from standstill and power generation mode operation. | 04-18-2013 |
20130106333 | APPARATUS AND METHOD OF DETERMINING ROTOR POSITION IN A SALIENT-TYPE MOTOR | 05-02-2013 |
20130193888 | SENSORLESS ROTOR POSITION DETERMINATION FOR A WOUND FIELD SYNCHRONOUS MACHINE - A rotor position determination and tracking system for a dynamo electric machine includes a first AC power supply to inject a carrier wave into a main stator of the dynamoelectric machine and a second AC power supply to inject an excitation voltage or current into an exciter stator of the dynamo electric machine. A plurality of current sensors and voltage sensors located at the exciter input lines sense current and voltage thereat. A first control logic receives the sensed current and voltage and outputs an estimated rotor position. A second control logic receives an estimated exciter field voltage or current rotating wave form angle and filtered sensed current or voltage signals from the first control logic and utilizes a known main stator carrier frequency to determine the rotor position. The rotor position is input into the first control logic to calibrate the first control logic for tracking of the true rotor position. | 08-01-2013 |
20130241454 | METHOD AND PROCESSING UNIT FOR DETERMINING THE POSITION OF THE ARMATURE OF A SYNCHRONOUS MACHINE RELATIVE TO THE STATOR OF THE SYNCHRONOUS MACHINE - A method for determining a position of an armature of a synchronous machine relative to a stator of the synchronous machine includes the steps of applying to the synchronous machine a plurality of test current vectors, with each test current vector having identical current magnitude and a different angle in relation to an armature-related d,q coordinate system, during application of the test current vectors to the synchronous machine, determining values of a physical response quantity of the armature proportional to the q component of the test current vectors, determining a first harmonic of the determined values of the physical response quantity as a function of the angle, and determining the position of the armature relative to the stator as a zero crossing of the first harmonic where a first derivative of the first harmonic is positive. | 09-19-2013 |
20130314017 | Circuit and Method for Calibration of Sensorless Control of a Permanent Magnet Brushless Motor during Start-up - A system for controlling motor switching in a sensorless BLDC having a stator with three stator windings and a permanent magnet rotor. The system includes a controller unit comprising a control signal generator, a memory device, a processing unit, a signal acquisition device, and an analog-to-digital converter. A power stage controlled by the controller unit has a plurality of switches and drives two windings of the three stator windings with a pulse width modulation signal and leaves one stator of the three stator windings undriven. The processing unit acquires a demodulated measured voltage on the undriven winding. The processing unit calculates a threshold at which the power stage will change which two windings of the three stator windings are driven when the demodulated measured voltage surpasses the threshold. | 11-28-2013 |
20130342145 | SYSTEM AND METHOD FOR ISOLATING THE UNDRIVEN VOLTAGE OF A PERMANENT MAGNET BRUSHLESS MOTOR FOR DETECTION OF ROTOR POSITION - The system and method disclose for the controlling of sequential phase switching in driving a set of stator windings of a multi-phase sensorless brushless permanent magnet DC motor. A motor controller controls a power stage that drives two windings of a set of three windings in the motor with pulse width modulated signal. A plurality of voltage values on an undriven winding of the set of three windings are sampled within a window of time, wherein a period beginning when the driven windings are energized and ending when the driven windings are de-energized encompasses the window of time. The sampled voltage values are processed. When the processed voltage values exceed a threshold, the motor controller changes which two windings are driven. | 12-26-2013 |
20130342146 | METHOD AND SYSTEM FOR SWITCHING BETWEEN DIFFERENT TYPES OF OPERATION OF A SENSORLESS PERMANENT MAGNET BRUSHLESS MOTOR AT LOW OR ZERO SPEED TO DETERMINE ROTOR POSITION - The system and method disclose for the controlling of motor switching. The system includes a controller unit having a control signal generator, a memory device, a processing unit, a signal acquisition device, and an analog-to-digital converter. A power stage has a plurality of switches and receives a control signal from the control signal generator and a power signal from a power source. The power stage drives two windings of the set of three stator windings with a multi-state pulse and leaves one stator of the three stator windings undriven. The processing unit acquires a demodulated measured voltage on the undriven winding. The processing unit communicates with the power stage to change which two windings of the three stator windings are driven when the demodulated measured voltage surpasses a threshold. | 12-26-2013 |
20140070746 | CONTROL DEVICE AND METHOD FOR ESTABLISHING THE ROTOR ANGLE OF A SYNCHRONOUS MACHINE - A method for establishing the rotor angle of a synchronous machine. The method includes determining a first estimated value for the d-axis of the synchronous machine, feeding at least one refinement voltage pulse pair into the stator of the synchronous machine, the refinement voltage pulse pairs each distanced from the first estimated value for the d-axis of the synchronous machine by the same angular value in different directions, detecting the angle-dependent refinement current responses to the refinement voltage pulses, determining the angle-dependent refinement phase differences on the basis of the respective detected refinement current response, determining first estimated curves on the basis of at least some of the angle-dependent refinement current responses, determining second estimated curves on the basis of at least some of the angle-dependent refinement phase differences. and determining a refined estimated value for the d-axis of the synchronous machine on the basis of the estimated curves. | 03-13-2014 |
20140070747 | CONTROL DEVICE AND METHOD FOR ESTABLISHING THE ROTOR ANGLE OF A SYNCHRONOUS MACHINE - A method and a device for establishing the rotor angle of a synchronous machine. In one embodiment, the method includes the steps of feeding at least one initial voltage pulse of predefinable pulse length and pulse height into the stator of the synchronous machine, detecting the respective current response to the at least one initial voltage pulse, determining the respective phase difference on the basis of the respective detected current response, establishing at least one first estimated value by comparing the current response with a current response characteristic curve of the synchronous machine, establishing at least one second estimated value by comparing the phase difference with a phase difference characteristic curve of the synchronous machine, forming a multiplicity of differences between each of the first estimated values and each of the second estimated values, and determining an initial estimated value for the rotor angle of the synchronous machine on the basis of the determined difference having the lowest value. | 03-13-2014 |
20140117901 | Switched Reluctance Initial Rotor Position Estimation - A method of estimating an initial rotor position of a switched reluctance (SR) machine having a rotor and a stator is provided. The method may comprise the steps of driving a phase current in each of a plurality of phases of the SR machine to a predefined limit, performing an integration of a common bus voltage associated with each phase, determining a flux value for each phase based on the integrations, and determining the initial rotor position based on the flux values. | 05-01-2014 |
20140145659 | METHOD FOR DETERMINING THE ROTARY POSITION OF THE ROTOR OF AN ELECTRIC MACHINE - A method for determining the rotary position of the rotor of an electric machine, which includes star-connected phase conductors, wherein a measurement signal representing the rotary position of the rotor within a magnetic half-period is determined from the potential at the star point. At a measurement time a specified voltage is applied to the ends of all the phase conductors by forcing the star point to a specific potential. At a time following the measurement time a voltage that deviates from the specified voltage is applied to the ends of one of the phase conductors. Then the measurement signal is derived from the current that develops from the measurement time in a connection of the star point to the specified potential. | 05-29-2014 |
20140145660 | ROTATING ELECTRICAL MACHINE CONTROL DEVICE - A rotating electrical machine control device that applies a high frequency current to a rotating electrical machine including a rotor having saliency, estimates a magnetic pole direction of the rotor on the basis of a high frequency component contained in a voltage command as a response component to the high frequency current, and controls the rotating electrical machine. A high frequency superimposing section sets an estimated d-q axis rotating coordinate system, and a magnetic pole direction adjusting section sets a high frequency coordinate system having a phase difference of the high frequency current command with respect to the estimated d-q axis rotating coordinate system. A steady estimation error correcting section calculates a magnetic flux interference estimation error as an error of the estimated value of the magnetic pole direction which is caused by the d-q axis magnetic flux interference. | 05-29-2014 |
20140184120 | METHOD AND APPARATUS FOR ESTIMATING ANGLES IN A SYNCHRONOUS MACHINE - The invention relates to an apparatus for estimating angles in a synchronous machine ( | 07-03-2014 |
20140232311 | Method and System for Determining the Position of a Synchronous Motor's Rotor - To establish an initial/resting position of a permanent magnet rotor, all motor stator windings are stimulated (voltage applied thereto) in sequence, the time it takes for current in the stimulated stator winding to rise to a specific current value is measured for each stator winding and these time measurement results processed. From the measured time results rotor position to within 60 degrees is determined and the position sector is known prior to starting/rotating the motor. Once the rotor position is known, the next commutation point in a six step sequence is known before actually starting/rotating the motor. Position measurement winding stimulation may be interleaved with commutation pulses, or the unexcited stator winding may be stimulated between commutation pulses to the other two excited stator, wherein one of the two stator windings remains connected to the power and provides a current return path to the unexcited but stimulated stator winding. | 08-21-2014 |
20140292244 | CONTROL APPARATUS FOR SWITCHED RELUCTANCE MOTOR - A control apparatus is provided for controlling a multi-phase, switched reluctance motor. The control apparatus includes voltage adjusters, a controller, and a carrier signal generator. Each of the voltage adjusters adjusts a voltage applied to a corresponding one of voltage application targets on the same salient pole of a stator of the motor. The controller controls each of the voltage adjusters via a pulse-width modulation based on comparison between a command signal and a corresponding one of carrier signals, thereby controlling the voltage applied to the corresponding voltage application target to a command voltage indicated by the command signal. The carrier signal generator generates the carrier signals so that for at least one pair of the voltage application targets on the same salient pole of the stator, two of the carrier signals which respectively correspond to the pair of the voltage application targets are offset in phase from each other. | 10-02-2014 |
20150054441 | METHOD AND DEVICE FOR DETERMINING THE POSITION OF A BRUSHLESS ELECTRIC DRIVE - A method for determining the position of an at least two-phase, in particular three-phase bmshless electric drive comprising at least two phase windings, each of which has a first and a second terminal, a second terminal of a first phase winding being electrically connected to the first terminal of a second phase winding at a common connecting terminal. In order to be able to reliably determine the position of the electric drive even at low speeds, a voltage pulse is applied between the first terminal of the first phase winding and the second terminal of the second phase winding, the resulting voltage at the connecting terminal or at a third phase winding connected thereto is detected and the voltage ratio between the first phase winding and the second phase winding is determined therefrom, and the ratio between the variable inductances is determined from said voltage ratio. | 02-26-2015 |
20150295526 | ENHANCED INDUCTIVE SENSE USING MUTUAL INDUCTANCE - Methods and apparatus for determining rotor position in a motor including a rotor and stator windings. The method includes measuring inductive sense values for each pair of the stator windings by performing an inductive sense routine on the motor, measuring stator winding voltage values, induced by mutual inductance between windings, for each of the stator windings by performing a mutual inductance sensing routine on the motor, and determining the rotor position based on the inductive sense values and the stator winding voltage values. | 10-15-2015 |
20150340980 | DEVICE FOR DETERMINING A POSITION OF A ROTOR OF A POLYPHASE ELECTRIC MOTOR - A device for determining a rotor position in a polyphase electric motor having a first phase, a second phase and a third phase. A power control unit applies a first voltage on the first phase, and a second voltage on the second phase, the first voltage and the second voltage being periodic signals of opposite polarity, alternating between a first part and a second part of the alternating period, such as square waves. A sample unit samples a third voltage on the third phase for acquiring a first sample at a first instant in the first part and a second sample at a second instant in the second part, and a difference value between the first sample and the second sample. The difference value represents a mutual inductance between the stator coils due to the rotor position. A determination unit determines the rotor position based on the difference value. | 11-26-2015 |
20150381087 | Sensorless Control of Switched Reluctance Machines for Low Speeds and Standstill - A method for determining rotor position of a switched reluctance (SR) machine having a rotor and a stator is provided. The method may include injecting a test pulse into one or more idle phases of the SR machine, determining a decoupled flux value based at least partially on a total flux value corresponding to the test pulse and a mutual flux value, and determining the rotor position based at least partially on the decoupled flux value. | 12-31-2015 |
20150381090 | SENSORLESS SYSTEM AND METHOD FOR DETERMINING MOTOR ANGLE AT ZERO OR LOW SPEEDS - A system and method for determining electrical angles of electric motors at zero and low speeds without using angle sensors, and a system and method for estimating resistances and temperatures in electric motors, wherein the two systems and methods may be used separately or together. When used together, they substantially simultaneously estimate motor flux linkage, magnet flux, and motor resistance. In particular, the estimated magnet flux is used to derive the electrical angle and to estimate an average rotor temperature, and the estimated motor resistance is used to estimate the average stator temperature. A Kalman filter, which may be a linear Kalman filter or a Luenberger observer, is used to update state equations from which various motor parameters can be derived or estimated. The system and method which works for motors operating at zero and low speeds can be combined with systems and methods that work at high speeds. | 12-31-2015 |
20150381091 | SYSTEM AND METHOD FOR ESTIMATING MOTOR RESISTANCE AND TEMPERATURE - A system and method for determining electrical angles of electric motors at zero and low speeds without using angle sensors, and a system and method for estimating resistances and temperatures in electric motors, wherein the two systems and methods may be used separately or together. When used together, they substantially simultaneously estimate motor flux linkage, magnet flux, and motor resistance. In particular, the estimated magnet flux is used to derive the electrical angle and to estimate an average rotor temperature, and the estimated motor resistance is used to estimate the average stator temperature. A Kalman filter, which may be a linear Kalman filter or a Luenberger observer, is used to update state equations from which various motor parameters can be derived or estimated. The system and method which works for motors operating at zero and low speeds can be combined with systems and methods that work at high speeds. | 12-31-2015 |
20160134216 | Circuits and Methods of Determining Position and Velocity of a Rotor - A motor controller includes a square wave voltage generator and adding circuitry for adding the square wave voltage to a first drive voltage that is connectable to the stator windings of a motor. A current monitor for monitoring the input current to the motor as a result of the square wave voltage. A device for determining the position of the rotor based on the input current. | 05-12-2016 |
20160134217 | MOTOR, MOTOR SYSTEM, AND DETECTION METHOD OF MECHANICAL ANGLE OF MOTOR - A motor includes a stator and a rotor that is arranged opposite to the stator through a predetermined air gap. The stator is such that a plurality of coils are wound around respective slots for each of a plurality of phases. In the stator, the number of turns of one of the plurality of coils is different from those of the others for each of the phases. In the rotor, among a plurality of magnetic poles formed of a plurality of permanent magnets arranged in a circumferential direction of a core, a magnetoresistance of at least one magnetic pole is different from those of the others. | 05-12-2016 |
20160149443 | PERMANENT MAGNET MOTOR, POSITION ESTIMATION APPARATUS AND MOTOR DRIVE CONTROL APPARATUS - A permanent magnet motor is provided, which includes a rotor including a rotation axle and a plurality of magnetized rotor magnets on a periphery, which rotor magnets are magnetized to form alternately N-poles and S-poles; first and second ring-shaped-claw-pole units, whose inner circumferences face the rotor magnets, including a plurality of first and second claw-poles along the inner circumference, the first and the second claw-poles being closely adjacent to each other extending alternately in upward and downward axis directions of the rotation axle, bottom sides of the first and the second claw-poles forming a ring shape. A first opening portion is formed in a first joint surface of the first ring-shaped-claw-pole unit, to be joined to the second ring-shaped-claw-pole unit, and the second opening portion is formed in a second joint surface of the second ring-shaped-claw-pole unit, to be joined to the first ring-shaped-claw-pole unit. | 05-26-2016 |