Abstract: Methods and systems are provided for controlling an AC motor via an inverter. The method includes determining a delay-compensated offset based on a synchronous frame current, producing a current error based on a synchronous frame current and a commanded current, producing a voltage error based on an anti-windup offset and the current error, producing a commanded voltage based on the delay-compensated offset and the voltage error, and providing the inverter with the commanded voltage.

Abstract: A motor current calculation device includes a first wire, a current detecting unit, a decision unit, and a calculation unit. The first wire is configured and arranged to carry flow of a motor current that has been passed through a motor and a drive current that has been passed through a motor drive unit to drive the motor. The current detecting unit is configured and arranged to detect a sum of the motor current and the drive current flowing through the first wire. The decision unit is configured and arranged to determine a first detection result of the current detecting unit when the motor is not rotating as the drive current. The calculation unit is configured to calculate the motor current by subtracting the drive current determined by the decision unit from a second detection result of the current detecting unit when the motor is rotating.

Abstract: An inverter has an inverter circuit and a current detector. In the inverter circuit, upper-arm switching elements and lower-arm switching elements, which are connected to DC power supply, provide DC with pulse-width modulation (PWM) so as to output AC to a load. The current detector detects current of the load. With the structure above, the inverter calculates an average value of DC that flows between the DC power supply and the inverter circuit according to a product of an ON-period in which any one of the switching elements maintains ON and a current value detected by the current sensor.

Abstract: A surgical motor control device for controlling a surgical drive unit comprises a sensorless electric motor with M motor windings. The motor control device is configured to perform a method for controlling the drive unit. The motor control device be configured to control the drive unit using a multiphase PWM method. An improved method for controlling a surgical drive unit and an improved surgical drive system are also proposed.

Abstract: According to a method for driving a converter (4) in accordance with a period commutation pattern, a transition region (25) is provided between a sinusoidal commutation region (21) and a block commutation region (22) in the context of the commutation pattern, in which transition region (25) a phase voltage (<UL1>) output by the converter (4) is set in temporally constant fashion for a first subsection (t1) of each half-cycle (P1, P2) in the manner of block commutation, while the phase voltage (<UL1>) is set in temporally varying fashion for a second subsection (t2, t3) of the half-cycle (P1, P2) in the manner of sinusoidal commutation. An apparatus (5) which is suitable for carrying out the method has a control unit (6) which is designed to generate a switching signal (PWM) for the converter (4) in accordance with the above-described method.

Abstract: A control apparatus of an alternating-current motor includes an inverter which is connected to a direct-current source and outputs three-phase alternating currents to the alternating-current motor, a current detector which detects a current of the alternating-current motor, a voltage command/PWM signal generation unit which calculates an output voltage command of the inverter based on a signal from the current detector and generates a pulse width modulation signal to control a switching element arranged in the inverter based on the output voltage command, and a motor current imbalance compensation unit which generates a motor current imbalance compensation amount based on the current detected by the current detector. The pulse width modulation signal is directly or indirectly adjusted at the voltage command/PWM signal generation unit based on the motor current imbalance compensation amount in accordance with a driving state of the inverter.

Abstract: Circuitry for controlling motors, such as a brushless motor (BLM), is disclosed. The circuitry may comprise one or more inputs for receiving rotor position signals from one or more Hall effect sensors that detect the position of, for example, a BLM rotor. The circuitry may also comprise an input for receiving a pulse width modulated speed control signal. The circuitry generates one or more drive signals, each of which may comprise a logical combination (e.g., a logical AND combination) of the speed control signal and a rotor position signal, for controlling power switches that are coupled to electromagnets of the BLM.

Abstract: The present invention discloses a control system for controlling a motor for a heating, ventilation and air conditioning (HVAC) or a pump comprising: an opto-isolated speed command signal processing interface into which a signal for controlling a speed of the motor is inputted and which outputs an output signal for controlling the speed of the motor being transformed as having a specific single frequency; a communication device into which a plurality of operation control commands of the motor; an opto-isolated interface for isolating the plurality of operation control commands inputted through the communication device and the transformed output signal for controlling the speed of the motor, respectively; a microprocessor, being connected to the opto-isolated interface, for outputting an output signal for controlling an operation of the motor depending on the plurality of operation control commands and the transformed output signal for controlling the speed of the motor; a sensor, being connected to the motor,

Abstract: A system for controlling a trapezoidally (square wave) driven DC motor includes a unipolar commutation circuit coupled between a DC power supply and a brushless DC motor. The motor has three phases formed by respective stator windings coupled at respective proximal ends to a common node and having respective opposite ends remote from the common node. The commutation circuit drives the motor according to a commutation cycle including three primary steps. During each primary step, one of the phases is driven while the other two phases are not driven. Voltages at the remote ends of the undriven phases are sensed, and timing signals are generated at points where the voltages coincide. The timing signals are used to determine motor position and speed, and to synchronize the commutation cycle with motor position and speed. In one embodiment, the commutation cycle includes transitional steps between the primary steps for smoother operation.

Abstract: In an AC-input type brushless DC motor, a current control circuit controls an average current of an inverter circuit, a current indication circuit makes addition or subtraction, with respect to a reference current value, to the average current to be supplied to the inverter circuit such that the average current falls into a correlation indicated by a correlation indication circuit. The foregoing structure allows setting speed-torque characteristics of the brushless DC motor such that the torque increases at a higher rpm of the motor. The characteristics are good for driving a fan.

Abstract: A motor driving integrated circuit includes a data receiving circuit, a control circuit, and a pulse generating circuit. The data signal receiving circuit receives data signals inputted via a data signal input terminal. The control circuit controls the motor driving integrated circuit based on a first data signal received through the data signal receiving circuit. The pulse generating circuit generates a pulse signal for PWM (Pulse Width Modulation)—controlling a motor coil based on a second data signal received through the data signal receiving circuit. The pulse generating circuit includes a rectangular signal generating circuit configured to generate a plurality of rectangular signals different in pulse width, and a synthesizing circuit configured to synthesize the plurality of rectangular signals outputted from the rectangular signal generating circuit to generate the pulse signal with a duty ratio corresponding to the second data signal.

Abstract: A particularly high level of performance in a sensorless, electronically commutated multiphase electric motor can be achieved, wherein for one full cycle at least, one motor phase is controlled in an asymmetrical manner relative to a further motor phase by controlling a commutation angle of one motor phase by reduction relative to a corresponding commutation angle of the other motor phase. Alternatively or in addition, according to the aforementioned method, at least one motor phase is asymmetrically controlled by reduction by self-reference for a full cycle, a commutation angle being controlled by reduction relative to a preceding or subsequent commutation angle or the size of the intermediate angles between two commutation angles being varied, the reduced commutation angle always being preceded or followed by a measurement angle within which the relevant motor phase is switched at zero current for detecting the rotor position by measuring the counter-electromotive force.

Abstract: Current control circuit controls an output voltage of DC power supply so as to increase current passing through inverter circuit as the motor increases its the speed. The control offers an RPM—torque characteristic of the motor in which torque increases as the RPM increases. By virtue of the RPM—torque characteristic, a ventilating device employing brushless DC motor exhibits preferable air quantity—static pressure characteristic where less change in air quantity is expected even when a pressure loss—outside wind pressure, duct length or the like—varies.

Abstract: A drive system for a compressor of a chiller system includes a variable speed drive. The variable speed drive receives an input AC power at a fixed input AC voltage and a fixed input frequency, and provides an output AC power at a variable voltage and variable frequency. The variable speed drive includes a converter connected to an AC power source. The converter is arranged to convert the input AC voltage to a DC voltage. A DC link is connected to the converter and configured to filter and store the DC voltage from the converter. An inverter is connected to the DC link. A motor is connectable to the compressor for powering the compressor. A controller is arranged to control switching in the converter and the inverter. The controller is arranged to apply randomized pulse width modulation to vary the switching frequency of transistors in the converter and the inverter at each switching cycle. The motor may be a permanent magnet synchronous motor.

Abstract: An embodiment of the invention relates to a driver adapted to provide a drive signal with an adjustable waveform for an external bridge to control EMI. The driver includes a detector configured to measure a switching characteristic of a switch in the external bridge to produce the drive signal with an adjustable waveform characteristic. The driver includes an adjustable circuit element to adjust the waveform characteristic in response to the measured switching characteristic. The measured switching characteristic may be a derivative of a voltage of the switch in the bridge such as a derivative of a drain-to-source voltage of a half-bridge circuit. The driver may be formed with an amplifier with an adjustable gain controlled by the signal produced by the detector. The adjustable gain amplifier may be formed with a transistor coupled in series with a leg of a current mirror.

Abstract: A position sensorless drive method capable of driving a permanent magnet motor by an ideal sine-wave current and enabling the driving from an extremely low-speed range in the vicinity of zero-speed is provided. A neutral-point potential of the permanent magnet motor is detected in synchronization with a PWM waveform of an inverter. The position of a rotor of the permanent magnet motor is estimated from the variation of the neutral-point potential. Since the neutral-point potential is varied in accordance with the magnetic circuit characteristics of an individual permanent magnet motor, the position can be detected regardless of the presence of saliency of the permanent magnet motor.

Abstract: A motor controller for controlling a permanent magnet motor having a rotor having a permanent magnet and a stator having multiphase windings including a position detector generating and outputting rotor rotational position signal; a waveform data storage storing sinusoidal waveform data; a drive signal output section reading the waveform data from the waveform data storage at timings determined based on the rotational position signal and outputting a voltage signal corresponding to the waveform data to the windings through a drive section; a data history storage storing data corresponding to the voltage signal of previous control period; and an output data modifier that, when outputting the voltage signal in current control period, compares corresponding waveform data with previous waveform data, and if difference between the current and the previous data is equal to or greater than a predetermined value, current output data is modified by a portion of the difference.

Abstract: An embodiment of a motor controller includes a motor driver and a signal conditioner. The motor driver is operable to generate a motor-coil drive signal having a first component at a first frequency, and the signal conditioner is coupled to the motor driver and is operable to alter the first component. For example, if the first component of the motor-coil drive signal causes the motor to audibly vibrate (e.g., “whine”), then the signal conditioner may alter the amplitude or phase of the first component to reduce the vibration noise to below a threshold level.

Abstract: Reference signals are combined with a chop frequency signal in a pulse width modulator (PWM) to provide plural inputs to a multi-phase H-bridge amplifier. Also provided to the bridge amplifier is a high voltage DC input which is converted by the pulsed inputs to the bridge amplifier to a variable AC voltage for driving a motor. The AC drive voltage is also provided to a variable frequency voltage-controlled oscillators (VCOs) in a feedback arrangement, with the variable frequency VCO outputs heterodyned with each of plural outputs of a multi-phase ring oscillator to provide plural baseband signals having a constant phase relationship at a high frequency. The baseband signals form the aforementioned reference signals provided to the PWM in the feedback arrangement with closed loop control and frequency and phase discrimination using phase lock loop techniques for synchronous motor control over a range of DC-100 kHz with 0-25 MHz VCOs.

Abstract: An inverter control circuit controls transistors based on comparison of a voltage command wave with a carrier wave, when a magnitude of a voltage vector is equal to or less than a peak value of the carrier wave. The voltage command wave is a wave, which is offset to a maximum value side from a reference potential of the carrier wave so that a maximum value of the voltage command wave equals a peak value of the carrier wave. The inverter control circuit makes an on-period of the transistor on a positive bus side longer than that of the transistor on a negative bus side by using the command voltage. The amount of electricity charged in a capacitor is reduced in comparison with a case in which the voltage command wave is used. Thus, thermal loss of a stator coil and a diode on the positive bus side is reduced.

Abstract: Methods and apparatus are provided for sensing currents on a plurality of phases and determining current information therefrom. The multi-phase boost converter includes a single sensor coupled to all of the plurality of phases and a controller coupled to the sensor for determining the current information in response to currents on each of the plurality of phases sensed by the sensor. The sensing method utilizes the gate drive signals and the DC current sensor output to calculate the currents on each of the plurality of phases sensed by the sensor.

Abstract: The invention specifies a circuit arrangement (1, 20) for controlling a brushless electric motor (37) with a control chip (2), particularly a microcontroller, which has a number of PWM contacts (8), which can be used to output a PWM signal, and a number of commutation contacts (5, 5?, 6, 6?, 7, 7?), which can be used to output a commutation signal. In this case, provision is made for at least one commutation contact (5, 5?, 6, 6?, 7, 7?) to be alternately controllable as an input and an output, for the at least one commutation contact (5, 5?, 6, 6?, 7, 7?) to have its output electrically connected to a PWM contact (8), and for the commutation contact (5, 5?, 6, 6?, 7, 7?) connected in this manner to be able to be contacted for the purpose of tapping off a control signal. Such a circuit arrangement (1, 20) increases the control options for a given control chip (2). The number of PWM sources required is reduced.

Abstract: A control device (2??) for an AC-DC current converter associated with a polyphase synchronous rotary electrical machine. The AC-DC current converter contains, for each phase, a branch of two power switches in series, known as high and low (25). The control device (2??) contains means of generating a signal (?(t)) representing the angular position of the rotor. The control device contains one or more digital tables (20H, 20B) addressed by the signal of the angular position of the rotor (?(t)) and delivering at their outputs binary control signals (200H-202H, 200B-202B), each controlling one branch of power switches (25).

Abstract: A load driving device includes a driver that supplies drive current to a load having an inductance component, a current sensing resistor that generates sensed voltage corresponding to switching current that flows in the driver, a switch circuit that delivers one of the sensed voltage and a predetermined bias voltage selectively, a comparator that compares a selected voltage of the switch circuit with a predetermined reference voltage, and a logic circuit that generates a drive control signal for the driver based on a comparison output signal of the comparator, so as to perform constant-current chopping control of the drive current with improved stability of the constant-current chopping control while avoiding malfunction due to noise.

Abstract: Methods and systems are provided for controlling an AC motor via an inverter. The method includes determining a delay-compensated offset based on a synchronous frame current, producing a current error based on a synchronous frame current and a commanded current, producing a voltage error based on an anti-windup offset and the current error, producing a commanded voltage based on the delay-compensated offset and the voltage error, and providing the inverter with the commanded voltage.

Abstract: In one aspect, a control circuit to control a speed of a motor includes a PWM oscillator configured to generate a PWM output signal having a duty cycle. The speed of the motor is controlled by the PWM output signal to be proportional to the duty cycle. The control circuit also includes a duty cycle control circuit responsive to a duty cycle selection signal and coupled to the PWM oscillator. The duty cycle control circuit is configured to compare a voltage reference and a supply voltage. The duty cycle control circuit controls the duty cycle of the PWM output signal to be inversely proportional to the supply voltage.

Abstract: The invention relates to an electronically commutated motor (10) and to a method of controlling an electronically commutated motor (10). In order to reduce commutation noise, it is proposed to influence the working range of the power-stage transistors (20, 22) with the aid of a component (48), in such a way that each transistors produces, during energization of each respective stator winding, a substantially constant current through the stator winding (12, 14). Preferably, each power-stage transistor operates within a pinch-off range.

Abstract: The present invention discloses a control system for controlling a motor for a heating, ventilation and air conditioning (HVAC) or a pump comprising: an opto-isolated speed command signal processing interface into which a signal for controlling a speed of the motor is inputted and which outputs an output signal for controlling the speed of the motor being transformed as having a specific single frequency; a communication device into which a plurality of operation control commands of the motor; an opto-isolated interface for isolating the plurality of operation control commands inputted through the communication device and the transformed output signal for controlling the speed of the motor, respectively; a microprocessor, being connected to the opto-isolated interface, for outputting an output signal for controlling an operation of the motor depending on the plurality of operation control commands and the transformed output signal for controlling the speed of the motor; a sensor, being connected to the motor,

Abstract: Circuitry for controlling motors, such as a brushless motor (BLM), is disclosed. The circuitry may comprise one or more inputs for receiving rotor position signals from one or more Hall effect sensors that detect the position of, for example, a BLM rotor. The circuitry may also comprise an input for receiving a pulse width modulated speed control signal. The circuitry generates one or more drive signals, each of which may comprise a logical combination (e.g., a logical AND combination) of the speed control signal and a rotor position signal, for controlling power switches that are coupled to electromagnets of the BLM.

Abstract: An electric fan device includes a motor which drives an electric fan for a vehicle, a control switch which controls a motor current supplied to the motor, and a control unit which controls an on/off operation of the control switch with pulse-width modulation. The control unit outputs a PWM pulse having a main PWM pulse and a vibration reducing pulse within one cycle to the control switch.

Abstract: An electric motor control strategy includes using a low resolution position sensor that provides a square wave output signal. The position sensor information is converted into sinusoidal commutation signals for motor control that reduces torque ripple. In one disclosed example, square wave commutation is used at low motor speeds and a controller switches to sinusoidal commutation once a selected threshold speed of the motor is reached. In another disclosed example, sinusoidal commutation is used at all motor speeds with two different techniques for converting the square wave sensor signal into a sinusoidal commutation signal, depending on the motor speed.

Abstract: An inverter contains the following structure: an inverter circuit having upper-arm switching elements connected on the positive side of a DC power source and lower-arm switching elements connected on the negative side of the DC power source; a current sensor that detects current flowing between the DC power source and the inverter circuit; and a control circuit that not only effects control of the inverter circuit so that AC is fed to a motor from the inverter circuit according to an ON-period controlled by a PWM system, but also makes a correction to the ON-period so as to allow the current sensor to detect phase current. The control circuit determines an amount of the correction by judging a direction of current of a phase having an intermediate length of the ON-period.

Abstract: Reference signals are combined with a chop frequency signal in a pulse width modulator (PWM) to provide plural inputs to a multi-phase H-bridge amplifier. Also provided to the bridge amplifier is a high voltage DC input which is converted by the pulsed inputs to the bridge amplifier to a variable AC voltage for driving a motor. The AC drive voltage is also provided to a variable frequency voltage-controlled oscillators (VCOs) in a feedback arrangement, with the variable frequency VCO outputs heterodyned with each of plural outputs of a multi-phase ring oscillator to provide plural baseband signals having a constant phase relationship at a high frequency. The baseband signals form the aforementioned reference signals provided to the PWM in the feedback arrangement with closed loop control and frequency and phase discrimination using phase lock loop techniques for synchronous motor control over a range of DC-100 kHz with 0-25 MHz VCOs.

Abstract: A drive system for a multi-phase brushless motor comprises a single current sensor drive circuit, including switch means, switchable between a plurality of states. A controller is arranged to provide pulse width modulated drive signals to control the switch means so as to control the time that the drive circuit switches between said states in each of a series of pulse width modulation periods, and to: determine a demanded voltage parameter set, identify PWM periods during which the demanded voltage parameter set is such that neither two nominal corresponding state times, nor a higher number of equivalent state times producing the same net voltage, in a single PWM period, would allow a predetermined minimum time to be spent in a predetermined number of active states sufficient for current sensing.

Abstract: A motor control system and method implements non-trapezoidal motor control and meets established “fail passive” regulatory guidelines. In particular, a system and method of controlling a multi-phase brushless motor that includes a multi-pole permanent magnet rotor, and an individual, electrically isolated stator winding associated with each phase that includes a first terminal and a second terminal. A motor command is supplied to a motor control. The motor control is configured such that the first terminal of each stator winding is selectively coupled to a power source at a first duty cycle, and the second terminal of each stator winding is selectively coupled to a power source asynchronously with the first terminal of each stator winding at a second duty cycle.

Abstract: Brushless Multiphase Self-Commutation Control (or BMSCC), also known as Real Time Emulation Control (or RTLC), is a contact-less means for powering any electric apparatus with “conditioned” or “re-fabricated” multiphase electrical excitation that is synchronized to the movement of the electric apparatus. BMSCC inherently phase-locks the frequency of excitation to any speed or position of the electric apparatus being controlled by a natural electromagnetic processing means and as a result, the BMSCC is an Electromagnetic Self-Commutator. BMSCC should never be confused with any derivative of Field Oriented Control, which is the other means of conditioning speed-synchronized electrical excitation by iteratively performing “speed-variant-to-speed-invariant” transformations and frequency synthesis by the unnatural processing means of an electronic computer. The control flexibility of BMSCC realizes additional synergistic or complementary electric apparatus inventions as shown in the illustration.

Abstract: Converters are connected in parallel to each other. The converter boosts a voltage from a power storage devices based on a signal from an ECU and outputs the boosted voltage to a capacitor. The converter boosts a voltage from a power storage device based on a signal from the ECU and outputs the boosted voltage to the capacitor. The ECU generates the signals by using carrier signals having phases desynchronized with each other and identical frequencies, and outputs the generated signals to the converters, respectively.

Abstract: Current control circuit controls an output voltage of DC power supply so as to increase current passing through inverter circuit as the motor increases its the speed. The control offers an RPM—torque characteristic of the motor in which torque increases as the RPM increases. By virtue of the RPM—torque characteristic, a ventilating device employing brushless DC motor exhibits preferable air quantity—static pressure characteristic where less change in air quantity is expected even when a pressure loss-outside wind pressure, duct length or the like—varies.

Abstract: A method of and system for controlling a brushless direct current (BLDC) motor includes providing with a lookup table a predetermined corresponding desired revolution time (DRT) for the BLDC motor for an ambient temperature. A Hall device is used to measure an actual revolution time (RT) of the BLDC motor. DRT and RT are compared to change duration of a pulse width modulation (PWM) signal in response to the comparison result. The PWM signal is applied to one of two BLDC motor windings.

Abstract: A brushless electrical machine has at least one phase winding which produces magnetic flux in the machine. A controller controls the flux in the machine with reference to a demanded flux and a stabilisation signal which, in combination, enable the controller to operate in a stable manner in the presence of disturbances in the inputs or parameters of the controller. The controller is able to operate with either a hardware rotor position detector or with a sensorless position algorithm.

Abstract: Control of rotational speed of a direct current multi-phase brushless motor is provided using an apparatus and method that works at low speed but does not depend upon Hall effect sensors. An apparatus for accelerating rotation of the motor shaft has a power stage circuit coupled to a back Electromotive Force (EMF) sensor circuit and a microprocessor. The power stage pulses at a duty cycle less than 100% under control of the microprocessor. The back EMF sensor circuit measures an order with respect to voltage of at least one phase relative to one or more other phases during off-time. The microprocessor determines one or more phases to be pulsed, and the polarity of the pulses based on the measured order. A method for sustaining rotation pulses the phases, measures order with respect to voltage of at least one phase relative to one or more other phases, and updates commutation state based on the measured order.

Abstract: A method of tuning a DC brushless motor, wherein measurement of back EMF voltage is used to detect changes in the torque requirements caused by variation in the operating conditions of the DC brushless motor, the method including varying the timing of the driving signals to the motor to compensate for the changes in the torque requirements.

Abstract: A selector selects an analog signal group to be used for PWM control out of a plurality of analog signals output by a PWM controlled load. An AD converter AD converts the analog signal group and generates a digital signal group that becomes control data for duty ratio setting in a duty ratio setting register to provide the generated digital signal group to a control unit for controlling a PWM circuit. A duty ratio comparison circuit compares duty ratios set by the plurality of duty ratio setting registers. An AD conversion channel selection circuit controls an analog signal group selecting operation by the selector based on a comparison result of the duty ratio comparison circuit.

Abstract: A method capable of controlling brushless DC motor detects the magnetic pole positions of the rotor with a Hall component to produce a Hall signal correspondingly, generates a PWM signal based on an external control signal with a PWM generator, controls a switch circuit based on the PWM signal and the Hall signal with a driver such that switched output is capable of being sent to the current phase of the stator coils for rotating the rotor. Further, while the Hall signal is detected to be level-switched, the external control signal level increases or decreases corresponding to change of the level of the Hall signal with respect to the duty cycle of the PWM signal being controlled to increase to the preset duty cycle from 0 or to decrease to 0 from the preset duty cycle for eliminating both sharp wave in the current during switching and noise.

Abstract: Methods and apparatus for controlling a polyphase motor in implantable medical device applications are provided. In one embodiment, the polyphase motor is a brushless DC motor. The back emf of a selected phase of the motor is sampled while a drive voltage or the selected phase is substantially zero. Various embodiments utilize sinusoidal or trapezoidal drive voltages. The sampled back emf provides an error signal indicative of the positional error of the rotor. In one embodiment, the sampled back emf is normalized with respect to a commanded angular velocity of the rotor to provide an error signal proportional only to the positional error of the motor rotor. The error signal is provided as feedback to control a frequency of the drive voltage. A speed control generates a speed control signal corresponding to a difference between a commanded angular velocity and an angular velocity inferred from the frequency of the drive voltage.

Abstract: The brushless motor has a first and second drive member. The first drive member is equipped with M phase coil groups each having N electromagnetic coils where M is an integer of 1 or greater and N is an integer of 1 or greater. The second drive member has a plurality of permanent magnets, and is able to move relative to the first drive member. The first drive member has 2 (M×N) magnetic body cores. Each phase electromagnetic coil is coiled on a periodically selected magnetic body core at a ratio of 1 to 2M from among the arrangement of 2 (M×N) magnetic body cores.

Abstract: A motor driving device includes an output circuit, a control circuit, a backflow preventing diode, and a capacitor. The output circuit is driven by a first voltage, includes a switching element of which turning-on/off is switched according to a switching control signal, and outputs current to motor coils when receiving a pulse-width-modulated first voltage. The control circuit is driven by a second voltage, and includes a position detecting circuit that detects the position of a rotor of the motor and a switching circuit that generates the switching control signal on the basis of the detection result of the position detecting circuit in order to switch the turning-on/off of the switching element. The capacitor performs a charging operation by a voltage applied from an input terminal of the first voltage through the diode, and applies a voltage of a node between the diode and the capacitor to the control circuit.

Abstract: A particularly high level of performance in a sensorless, electronically commutated multiphase electric motor can be achieved, wherein for one full cycle at least, one motor phase is controlled in an asymmetrical manner relative to a further motor phase by controlling a commutation angle of one motor phase by reduction relative to a corresponding commutation angle of the other motor phase. Alternatively or in addition, according to the aforementioned method, at least one motor phase is asymmetrically controlled by reduction by self-reference for a full cycle, a commutation angle being controlled by reduction relative to a preceding or subsequent commutation angle or the size of the intermediate angles between two commutation angles being varied, the reduced commutation angle always being preceded or followed by a measurement angle within which the relevant motor phase is switched at zero current for detecting the rotor position by measuring the counter-electromotive force.

Abstract: The invention relates to a two-phase permanent magnet motor which is controlled by a frequency converter. The frequency converter is advantageously provided with a three-phase inverter having six switches that are controlled in such a manner as to minimize switching losses.

Abstract: A vector control system for a permanent magnet synchronous motor, using a current control equivalent output value, a frequency instruction value, a current detection value, an inference phase error value, and a motor constant, identifies a motor resistance equivalent or a resistance setting error equivalent. Next, the vector control unit, using the identified value, corrects a set value R* equivalent of a voltage instruction calculation unit and a n inference phase error calculation unit. Thereby, a vector control system for a permanent magnet synchronous motor can realize a robust control characteristic for changing of a resistance constant of a motor in a low rotation speed area under position sensor-less control. Further, a vector control system for a permanent magnet synchronous motor can be applied in common in a system performing inexpensive current detection.