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: A heating, ventilation and air conditioning (HVAC) system is provided. The system includes an integrated motor including a plurality of operating speeds and an input for selecting one of the plurality of operating speeds. The system further includes a system controller and an adjustment module. The adjustment module includes a plurality of operating modes each associated with one of the plurality of operating speeds and the ability to manually vary associations between the plurality of operating modes and the plurality of operating speeds. The adjustment module selects one of the plurality of operating modes on the basis of control commands received from the system controller and setting programmed or manually entered into and stored in the adjustment module and controls the integrated motor according to the operating speed associated with the selected operating mode.

Abstract: A power supply device for a variable rotation speed drive includes a free-running converter connected to a land-based power grid, and an inverter connected to the variable rotation speed drive. A direct-current cable electrically connects the DC side of the converter with the DC side of the inverter. The inverter includes a plurality of phase modules having an upper and a lower valve branches with least two series-connected, two-pole subsystems with distributed energy storage devices. The inverter is located on the seabed in immediate vicinity of the variable rotation speed drive. Signal electronics of the inverter is located on land. In this way, the distance between the power supply on land and the drive on the ocean floor can reach several hundred kilometers, with ocean depths of several kilometers.

Abstract: A motor control apparatus includes a phase sensing circuit, current sensing circuit, phase lock loop, controller and driving circuit. The phase sensing circuit detects a phase switching state of a magnetic pole of a motor circuit, then generates and outputs a phase switching signal to the phase lock loop during motor operation. The current sensing circuit detects current flowing through a coil of the motor to generate and output a current phase signal to the phase lock loop. The phase lock loop compares a phase difference between the phase switching signal and the current phase signal to generate and output a phase-switch controlling signal to the controller. The controller generates and outputs a driving signal to the driving circuit in accordance with the phase-switch controlling signal. The driving circuit controls the phase switching state of the magnetic pole to drive the motor in accordance with the driving signal.

Abstract: A motor load control apparatus capable of suppressing heat generation of an electronic switch and suppressing occurrence of noise associated with rotation of a fan and vibration of the fan is provided. A switch section (17) in which a first electronic switch (T1) and a second electronic switch (T2) are connected in parallel is provided, and the first electronic switch (T1) is driven by a PWM signal with a predetermined duty ratio and a predetermined frequency and the second electronic switch (T2) is driven in a state of delaying the PWM signal by which the first electronic switch (T1) is driven by a predetermined time. Consequently, as compared with the case of one electronic switch, a heating value of each of the electronic switches can be reduced and radiation measures of the whole apparatus can be reduced. Further, noise or vibration occurring by PWM control can be reduced by changing delay time at random.

Abstract: The present disclosure related to a control method for a sensorless motor with energy recovery ability, using which duty cycle of a sensorless motor can be changed by the control of complementary switches so as to enable the sensorless motor to switch between a high efficiency driving operation and an energy recovery operation while being activated. Thereby, the conduction loss and the wear and tear to the switches can be minimized while simultaneously enhancing the energy recovery efficiency and thus improving the battery life.

Abstract: A bi-power motor controlling system includes a motor, a system apparatus and a motor controlling apparatus. The system apparatus has a rotational-speed target value for determining the targeted rotational speed of the motor. In addition, the system apparatus outputs a first power and a second power to the motor and the motor controlling apparatus, respectively. The motor controlling apparatus detects the motor to obtain a first rotational-speed value of the motor, and then adjusts the rotational speed of the motor to a second rotational-speed value according to the first rotational-speed value. Then, the motor controlling apparatus further generates a rotational-speed feedback signal to the system apparatus. The system apparatus adjusts the outputted first power in accordance with the rotational-speed feedback signal to make the rotational speed of the motor reach the rotational-speed target value.

Abstract: A motor driving device driving coil terminals of a three-phase motor to flow three-phase currents includes: a pulse modulator generating three-phase modulation pulses, each of which has a duty ratio in accordance with a voltage level of a coil terminal; a shift amount selection unit selecting a first shift amount corresponding to at least one of two predetermined amounts according to a pulse width of the longest pulse among the three-phase modulation pulses; a first shift unit shifting the second-longest pulse among the three-phase modulation pulses backward by the first shift amount to delay timing; a second shift unit shifting the third-longest pulse among the three-phase modulation pulses backward by a predetermined second shift amount to delay timing; and an inverter driving each of the coil terminals by switching a driving power supply with the three-phase modulation pulses by reflecting shift results of the first and second shift units.

Abstract: A method controls a motor, especially for opening and closing a door. The motor is controlled by a pulse width-modulated switching signal that is divided into a specifiable number of pulse width-modulated control signals for actuating a bridge circuit to a corresponding number of functional channels. The functional channels are switched off independently from each other by at least one or more switch-off signals on at least one switching circuit of a number of independent switching circuits corresponding to the number of functional channels.

Abstract: When it is determined that a rotor is initially in a stationary state, a current vector is applied to a coil by a vector control method so as to rotate the rotor in a forward direction from a present position of the rotor regardless of a predetermined start position of the rotor. Therefore, a motor can be stably started with less power consumption and noise/vibration.

Abstract: A first and a second drive current for an electrical drive are generated as a function of a nominal value for a movement variable, such as drive torque or rotational speed. An alternating magnetic field is generated in the drive by the drive currents. The alternating magnetic field causes movement of the drive. A first measurement signal and a second measurement signal are determined by a measurement device. The two measurement signals represent the first drive current and the second drive current. A field-producing direct-axis current component and a torque-producing quadrature-axis current component are determined as a function of the first and second measurement signals. In addition, an actual value of the movement variable is determined as a function of the measurement signals. At least one of the drive currents is generated with a variable test current component which forms a test pattern for checking the measurement device.

Abstract: Power conversion systems and methods are provided for driving a plurality of motor loads, in which an autotransformer receives AC input currents and provides a plurality of multiphase outputs at a non-zero phase angle relative to one another, and the individual multiphase outputs are provided to corresponding motor drives with rectifiers to convert the multiphase outputs to DC electrical power, and inverters to convert the DC power to AC to drive corresponding motor loads.

Abstract: A motor controller comprises a processor selectively outputting an on-signal to either one of an upper arm switching element and a lower arm switching element based upon a detected position by the position sensor, gate drivers inputting a driving voltage to the gates of the switching elements by shifting a level of the on-signal from the processor to the upper arm switching element and a bootstrap capacitor configured to be charged while the upper arm switching element is turned off and to behave as a voltage supply for the gate driver while the upper arm switching element is turned on. The processor is configured to reduce a set duty ratio when the set duty ratio is equal to or larger than a predetermined value (e.g. 80 percents) and a rotational position of the motor does not change for a first predetermined time. This motor controller can prevent the switching element from a burnout even if the motor is locked.

Abstract: Methods, systems and apparatus are provided for controlling operation of and regulating current provided to a five-phase machine when one or more phases has experienced a fault or has failed. In one implementation, the disclosed embodiments can be used to synchronously regulate current in a vector controlled motor drive system that includes a five-phase AC machine, a five-phase inverter module coupled to the five-phase AC machine, and a synchronous current regulator.

Abstract: Methods, system and apparatus are provided for increasing voltage utilization in a five-phase vector controlled machine drive system that employs third harmonic current injection to increase torque and power output by a five-phase machine. To do so, a fundamental current angle of a fundamental current vector is optimized for each particular torque-speed of operating point of the five-phase machine.

Abstract: An inverter controller controlling an inverter main circuit, the inverter controller including: a PWM signal generating part which generates a PWM signal to control on-off of a plurality of switching elements configuring the inverter main circuit; an operating state detecting part which detects an operating state of a load based on a direct current bus voltage of the inverter main circuit, a motor current which flows between the inverter main circuit and the load and an operation instruction to the load; a gate resistance selecting signal generating part which generates a gate resistance selecting signal corresponding to the operating state of the load; and a gate resistance selecting part which selects gate resistances connected to gate terminals of the switching elements of the inverter main circuit by using the gate resistance selecting signal.

Abstract: A control apparatus for an AC motor controls an inverter in a pulse width modulation scheme to feed a coil current to a stator coil of a stator. A pattern switching mechanism switches a control pattern to a first pattern or to a second pattern; a first pattern calculating mechanism calculates a control signal using a first pattern parameter; a second pattern calculating mechanism calculates a control signal using a second pattern parameter; an offset calculating mechanism calculates a difference between a control signal of an old pattern and a control signal of a new pattern, and reflects the offset amount on the control signals; and a control output mechanism calculates a final control output signal on the basis of the control signals, and transmits the final control output signal to the inverter.

Abstract: A driving device for three-phase alternating current synchronous motors controls state of charge of a capacitor, and a three-phase alternating current synchronous motor is started prior to the operation of the synchronous motor. Prior to control by a normal operation control unit, the state of charge of the capacitor is controlled by an initial state control unit and a synchronization control unit. Passage of large current through the capacitor immediately after the start of the execution of control by the normal operation control unit is suppressed. As a result, the operating state of the three-phase alternating current synchronous motor does not become unstable and the execution of control by the normal operation control unit can be started with the output voltage of the capacitor stable.

Abstract: In a method and control system for controlling a brushless, electronically commutated electric motor (M), a three-phase source AC voltage (UN) is rectified and fed to a DC link voltage (UZK), which is supplied to an inverter (2) via a slim DC link circuit (6). A motor control unit (10) for PWM pulsing controls the inverter for commutating the electric motor (M) and adjusting the motor speed with a variable duty cycle (A). The duty cycle (A) is influenced by a compensating factor (k) such that the product of the DC link voltage (UZK) and a resulting DC link current (IZK) is kept constant in the link circuit (6). The DC link voltage (UZK) is monitored. When a first threshold value (UZKac.max1) of an AC component (UZKac) is exceeded, the compensating factor (k) is modified to lower the current AC component (UZKac) below the threshold value (UZKac.max1).

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 method and an apparatus are provided for balancing current for each of a plurality of similar phases of a DC/DC boost converter. The method includes the step of measuring a voltage drop of each of the plurality of similar phases at predetermined times by measuring the voltage drop across each phase switching device when current is flowing through the switch. The method also includes the steps of calculating current information for each of the plurality of similar phases in response to the voltage drop measured for each of the plurality of similar phases and balancing current for each of the plurality of similar phases in response to the current information of each of the plurality of similar phases.

Abstract: Method for determining the angular position of the rotor of a mechanically commutated DC servo motor (5), which is arranged in the transverse branch of a bridge circuit, and the armature current of which is preset by an electromechanically activated switching device (28), —with a control and analysis unit (17) which analyzes the current ripple (3) present in the armature current (2) and attributable to the mechanical commutation, characterized in that—from each switch contact (6, 7) of the switching device (28), a contact-voltage feedback signal (9, 10) is fed back to the control and analysis device (17) by means of a feedback circuit (20), and in that the control and analysis unit (17), by using the at least one contact-voltage feedback signal (9, 10), determines a contact vibration time interval (4) and performs an estimate of current ripple (3) during this contact vibration time interval (4), during which an analysis of the current ripple due to contact vibrations which are caused by a switching process of

Abstract: Some embodiments provide a system that generates a coil switching signal for a brushless DC motor. During operation, the system determines a magnetic field of the brushless DC motor at a first time and a magnetic field of the brushless DC motor at a second time. Then, the coil switching signal is generated based on a relationship between the magnetic field determined at the first time and a first predetermined threshold, and the magnetic field determined at the second time and a second predetermined threshold.

Abstract: An electronically commutated motor (ECM) often employs a Hall sensor for reliable operation. Even when a Hall sensor is omitted from a motor having a plurality of stator winding phases (24, 26) and a permanent-magnet rotor (22), one can reliably detect direction of rotation of the rotor by the steps of: (a) differentiating a voltage profile obtained by sampling either (1) induced voltage in a presently currentless phase winding or (2) voltage drop at a transistor, through which current is flowing to a presently energized phase winding, and (b) using such a differentiated signal (du—24?/dt, du—26?/dt) to control current flow in an associated phase winding. In this manner, one obtains reliable commutation, even if the motor is spatially separated from its commutation electronics.

Abstract: Method for starting a single-phase synchronous electric motor using permanent magnets with simple and cost-effective implementation, said method comprising a step of application of a control logic of the switch that provides a first and a second condition for switching on: the first condition being verified when a detected counter electromotive force signal has the same sign as an electrical grid voltage signal; the second condition being verified when said counter electromotive force signal has the same sign as its first derivative value.

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: In a driving apparatus for a three-phase synchronous motor, in which a battery is connected between a neutral point of a stator coil and a negative-pole bus, a control circuit acquires three-phase AC currents. The control circuit checks whether a neutral-point electric current is contained in an electric current detected by an electric current detecting section. Based on the check result, the control circuit checks whether electric current values for three-phases containing the neutral-point electric current are set together or electric current values for three-phases excluding the neutral-point electric current are set together to acquire the three-phase AC currents for driving the motor.

Abstract: A system and method are provided for constant loading in AC power applications where at least one turn-on point of at least one half cycle of a modulating sine wave is randomly selected; at least one turn-off point is determined; and at least one slice located between the at least one turn-on point and turn-off point is removed. The slices may be removed by utilizing insulated gate bipolar transistors or field effect transistors.

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 (20 H, 20 B) addressed by the signal of the angular position of the rotor (?(t)) and delivering at their outputs binary control signals (200 H- 202 H, 200 B- 202 B), each controlling one branch of power switches (25).

Abstract: A brushless motor control device according to the present invention drives a brushless motor including a stator having coils of three phases U, V, and W and a neutral line, and a sub coil provided in any one phase of the phases U, V, and W, for detecting a voltage induced in the coil of the one phase, and the brushless motor control device carries out a conduction control function, for the respective phase coils of the brushless motor, that performs a 120° conduction when a rotation speed of the brushless motor is lower than or equal to a predetermined rotation speed, and that performs a 180° conduction when the rotation speed is higher than or equal to the predetermined rotation speed, and the brushless motor control device includes a motor control unit that controls the brushless motor based on information of the rotor stop position when activating the brushless motor, controls the brushless motor based on the first rotor position information when in the 120° conduction, and controls the brushless motor bas

Abstract: An electric compressor controller includes a compressor that compresses refrigerant of an air conditioning system; a motor that drives the compressor; an inverter that selectively control switching elements based on PWM pulse signals to supply drive power to the motor and heats the refrigerant by heat generated due to switching of the switching elements during a heating operation; temperature detectors each detects junction temperature of each of the switching elements; a drive controller that supplies the pulse signals to the inverter to control the inverter; and a slope varying unit that variably controls precipitous degree of rising/falling slope waveforms of the pulse signals based on the junction temperature detected by the temperature detectors. According to the electric compressor controller, efficiency for heating refrigerant is improved, so that its own heating ability is improved.

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: An inverter apparatus comprises an inverter circuit using pairs of switching elements. The pseudo AC voltage of each phase of this inverter circuit is controlled by pulse modulation using pulses generated by a PWM generator, and the pseudo AC voltages are applied to a power supplied load. The average voltage of respective phases of the output voltages applied to the power supplied load is detected as a virtual neutral voltage corresponding to the neutral voltage of the power supplied load by detecting the voltage at a common node where the phases of a voltage detecting circuit provided between the inverter circuit and the power supplied load are connected. The detected virtual neutral voltage is fed back for controlling the output duty of each phase by the PWM generator. Thus the output voltage of each phase from the inverter circuit is controlled so as to become a target output voltage. The target output voltage can be accurately obtained stably at all times.

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: Circuitry for controlling a motor, 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 drive signal having a plurality of driving intervals. Each drive signal may control power switches during its driving intervals, the power switches being coupled to electromagnets of the BLM. The circuitry may cause the driving intervals of a first drive signal to be temporally spaced from the driving intervals of a second drive signal.

Abstract: An electronically commutated motor (ECM) often employs a Hall sensor for reliable operation. Even when a Hall sensor is omitted from a motor having a plurality of stator winding phases (24, 26) and a permanent-magnet rotor (22), one can reliably detect direction of rotation of the rotor by the steps of: (a) differentiating a voltage profile obtained by sampling either (1) induced voltage in a presently currentless phase winding or (2) voltage drop at a transistor, through which current is flowing to a presently energized phase winding, and (b) using such a differentiated signal (du—24?/dt, du—26?/dt) to control current flow in an associated phase winding. In this manner, one obtains reliable commutation, even if the motor is spatially separated from its commutation electronics.

Abstract: A motor control device includes a dq-axis current control unit for generating a dq-axis voltage reference based on a dq-axis current reference and a dq-axis current signal, an initial magnetic pole position estimation unit for estimating a magnetic pole position of the motor upon power-on to generate a magnetic pole position signal, and a magnetic pole position estimation precision confirming unit for supplying a current in a d-axis direction after generation of the magnetic pole position signal with the initial magnetic pole position estimation unit, and checking an error of the magnetic pole position signal based on an angle of movement of the motor.

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: A power inverter comprises a power module connected at least to a rotating electric machine, a gate drive circuit board which supplies switching power to the power module, and a rotating electric machine control circuit board which supplies a signal for controlling the waveform of the switching power to the gate drive circuit board. A noise reduction board is formed on a board different from the rotating electric machine control circuit board. The configuration of the noise reduction board is such that various signals for forming a signal for controlling the waveform of the switching power by means of the rotating electric machine control circuit board are inputted through the noise reduction board to the rotating electric machine control circuit board.

Abstract: A motor and a motor speed control system are disclosed. Two power signal lines and one feedback/speed-control signal line are coupled between a control device and the motor. The two power signal lines electrically connect the control device to the motor. The feedback/speed-control signal line bi-directionally transmits signals coming from the control device to the motor and from the motor to the control device.

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 motor driving circuit for full-wave single-phase driving a motor includes a position detection unit, a turn-on signal generation unit, and switching devices that define an H-bridge circuit. The turn-on signal generation unit includes a differential amplifier arranged to produce a trapezoid wave signal, and a square wave generation circuit arranged to produce a square wave signal, wherein the trapezoid and the square wave signals are respectively supplied to control terminals of lower switching devices in the H-bridge circuit. Further, one of the lower switching devices is turned on and off according to a voltage level of the square wave signal, and the remaining lower switching device is turned on and off when a voltage of the trapezoid wave signal becomes higher than an operation voltage of the remaining lower switching device, wherein a non-conducting interval is provided for the motor coil according to the operation voltage.

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: 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 device for determining the position of the rotor of a rotating electrical machine. The invention is characterized in that the device comprises a plurality of magnetic field sensors stationary relative to the stator and adapted to deliver multiphase electric signals representing a magnetic field detected by the sensors, and means for processing the multiphase electric signals by an operator capable of providing diphase signals depending on the position of the rotor. The invention is applicable to rotating electrical machines used in the automotive industry.

Abstract: A method controls a motor, especially for opening and closing a door. The motor is controlled by a pulse width-modulated switching signal that is divided into a specifiable number of pulse width-modulated control signals for actuating a bridge circuit to a corresponding number of functional channels. The functional channels are switched off independently from each other by at least one or more switch-off signals on at least one switching circuit of a number of independent switching circuits corresponding to the number of functional channels.

Abstract: A commutation circuit for driving a brushless DC motor is controlled according to a commutation cycle composed of alternating primary steps and transitional steps. The commutation circuit includes pairs of field effect transistors coupled in series between the high voltage and low voltage terminals of a DC power supply. Output terminals between each pair of transistors are individually coupled to the phases of a DC motor. A controller operates the commutation circuit to selectively set the phases at active and inactive states. The controller further employs a plurality of voltage control functions individually associated with the motor phases to selectively modulate the voltage applied to one of the phases during the active states, to provide transitional steps in the commutation cycle during which the applied voltage is modulated to reduce its magnitude with respect to the high voltage or the low voltage.

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: 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 disclosed motor driver control device is configured to control a plurality of switching devices that drive a motor. The motor driver control device includes a duty control unit configured to restrict a duty of a first pulse width modulation signal generated by comparing an oscillator signal generated at a predetermined cycle and a pulse generator signal so as to generate a second pulse width modulation signal, and a switching device control signal generator unit configured to include a logic circuit that operates the second pulse width modulation signal as a clock and configured to generate a switching device control signal controlling the plurality of switching devices based on the clock of the logic circuit of the switching device control signal generator unit.