Abstract: Systems and methods for sensorless trapezoidal control of brushless DC motors provide effective high-torque startup and low speed operation without the use of Hall effect sensors or encoders during motor operation. The systems and methods also provide the ability to boost signal-to-noise ratio for motor startup and low speed operation via an augmenting supply voltage. Sampling architectures and current-dependent inductance modeling architectures for the control systems are also described.

Abstract: A motor driving device for driving a motor is provided. The motor driving device includes: a driver outputting a drive signal for driving the motor to the motor; and a controller controlling a duty ratio of the drive signal based on three control parameters which are an initial duty ratio, a duty ratio increasing speed, and a target duty ratio. The controller has a normal control mode in which each of the three control parameters is a predetermined value, and a cryogenic control mode in which at least one of the three control parameters is a smaller value than in the normal control mode.

Abstract: An electric vehicle includes a traction motor, an inverter that supplies the motor with an alternating current, three current sensors that respectively measure current of each phase of the alternating current output by the inverter, the alternating current being a three phase alternating current; and a controller that controls the motor through the inverter. The controller is configured to, when one of the current sensors becomes unusable, identify the unusable current sensor while controlling the motor with a d-axis voltage command value set to zero and a q-axis voltage command value set to a non-zero value.

Abstract: The invention relates to an elevator comprising at least one elevator car moved by at least one elevator motor, which elevator motor is driven by a frequency converter controlled by a control device of the elevator, the frequency converter comprising a rectifier bridge, an inverter bridge and a DC link connected in-between, the inverter bridge being connected to the elevator motor and the rectifier bridge being connected to AC mains via three phase supply lines comprising an LCL-filter and a mains switch.

Abstract: A motor control system includes a reference current generator that generates a reference current based on a command, a motor voltage providing device that generates a phase voltage based on the reference current, a high frequency voltage, and a feedback current and provides a motor with the phase voltage, and a high frequency voltage generator that generates the high frequency voltage corresponding to a magnitude of voltage generated based on the reference current and the feedback current.

Abstract: The present disclosure includes techniques for implementing a variable speed drive (VSD) in an environmental conditioning system to facilitate mitigating or eliminating system faults. The variable speed drive drives a motor during on-cycles and heats motor windings of the motor during off-cycles. The variable speed motor drive includes a rectifier that converts alternative-current (AC) power input to a direct-current (DC) power output, a DC bus that is coupled to the rectifier and includes a DC bus transistor, and an inverter. The DC bus transistor pre-charges a DC capacitor of the DC bus to drive the motor during on-cycles and receives a gate pulse with a duty cycle based on a differential temperature, where the gate pulse heats the motor windings. The inverter receives the gate pulse applied to the DC bus transistor and transmits it a motor winding to prevent moisture on the motor winding.

Abstract: There is provided an electrically driven vehicle that well balances calculation volumes and communication volumes of two control devices configured to drive and control motors for driving. The electrically driven vehicle comprises at least one motor for driving and a first control device and a second control device configured to control the motor. The first control device is configured to calculate a target torque that is to be output from the motor, based on information including an accelerator position, to calculate a current command based on the calculated target torque, and to send the calculated current command to the second control device. The second control device is configured to use the current command, a phase current of the motor and a rotational angle of the motor such as to drive the motor by feedback control.

Abstract: Provided in this disclosure is a dual-motor propulsion assembly, and corresponding methods of operation, that is configured for use in an electric aircraft. Dual-motor propulsion assembly provides redundant systems by including vertically stack motors, where one motor powers a propulsor of the assembly if the other motor malfunctions or becomes inoperative.

Abstract: Provided is an electronic timepiece capable of suppressing variation in the drive speed of a rotor, and driving a motor at a constant speed. The electronic timepiece has a driver; a controller that controls the driver to the on state or the off state according to a current flowing through a coil of a motor; a detection signal output device configured to output a detection signal when the on time or the off time, which are the continuous time of the on state and off state of the driver, meets a specific condition; a reference signal output device that outputs a reference signal used as a reference of a drive speed of the motor; and a drive cycle adjuster that compares the output timing of the detection signal and the reference signal, shortens the drive cycle when the detection signal is output after the reference signal, and when the detection signal is output before the reference signal, lengthens the drive cycle of the motor.

Abstract: The disclosure relates to an autonomous apparatus, moving and performing preset work in a defined working area, the autonomous apparatus including an energy module supplying energy to the autonomous apparatus, a motor, a sensor circuit, and a control circuit, the motor obtaining the energy from the energy module, to drive the autonomous apparatus to move and/or work in the working area, the sensor circuit detecting working parameters and environmental parameters of the autonomous apparatus, and transmitting detection results to the control circuit, the control circuit controlling the operation of the motor according to a signal transmitted by the sensor circuit, where the motor is a sensorless brushless motor, and before the motor rotates, the control circuit measures a resistance value of the motor, and estimates, one the basis of the resistance value of the motor, a rotor position of the motor, so as to control the operation of the motor.

Abstract: A long-distance speed control system for a brushless DC motor of a fan is provided. The long-distance speed control system includes a switch connected with a mains power supply, a switch circuit, a voltage detection module, a power cord, a processing unit, and a drive unit, which can control the multi-stage rotational speed of the motor. In the field of brushless DC motors for fans, there is no need to use analog-to-digital conversion chips between the mains power supply and the processor, having the advantages of low cost, environmental protection, and reduction of waste of earth resources. Besides, the switch, the switch circuit and the power cord can withstand the mains power supply, having the advantages of less signal attenuation and long-distance transmission.

Abstract: A control facility for a DC link converter includes a power regulator, which determines, based on an actual power determined at least partially at the feed converter, a power-based desired moment component for a kinetic energy store. The invention also relates to a DC link converter controlled by the control facility and to a forming machine, such as a press, with a DC link converter controlled by the control facility.

Abstract: A voltage saturation prevention algorithm used as at least part of a method of controlling an electric vehicle, wherein the electric vehicle comprises an electric motor, a controller, and an inverter. The controller receives a control signal with an instruction to operate the electric motor, then sends a switching signal corresponding to the control signal to the inverter, wherein the inverter provides a plurality of output signals for operation of the electric motor. The method includes determining the expected amplitude of the plurality of output signals based on the instruction to operate the electric motor, calculating the amount of modification of the plurality of output signals required to prevent the expected amplitude from reaching a saturation value, and modifying, based on the calculation, the instruction to operate the electric motor to prevent the expected amplitude from reaching the saturation value. The method is implemented in software, without any additional hardware.

Abstract: A method includes adjusting currents of a plurality of windings of a motor through a plurality of power converters coupled to the plurality of windings so that the number of poles and the number of phases of the motor are dynamically adjustable, and injecting a plurality of high-order harmonic currents into the plurality of windings of the motor through controlling the plurality of power converters to improve a performance index of the motor.

Abstract: To provide a servo motor controller that can quickly and effectively stop an industrial machine at a particular position even if operation speed is relatively low when a fixed position stop command is issued. The servo motor includes a speed comparison unit configured to compare speed at a time of a fixed position stop command with a first speed, a fixed position stop operation determination unit configured to determine an operation method at the time of the fixed position stop command, and a fixed position stop control unit configured to control the servo motor based on the determined operation method.

Abstract: A method for expanding features of a gas engine replacement device that drives power equipment including controlling, by an electronic processor of the gas engine replacement device, a power switching network to selectively provide power from a battery pack to rotate a motor of the gas engine replacement device. A module interface of the gas engine replacement device receives an external electronics module. A type of the external electronics module received by the module interface is detected by the electronic processor of the gas engine replacement device. The gas engine replacement device is configured by the electronic processor based on the type of the received external electronics module. The electronic processor communicates with the external electronics module via the module interface.

Abstract: An over-current protection circuit for a motor capable of selecting one of a plurality of connection states has a plurality of decision circuits, a combining circuit, and a nullifying circuit. The combining circuit combines results of the comparisons in the plurality of decision circuits. The nullifying circuit nullifies part of the comparisons in the plurality of decision circuits. The number of outputs of the over-current protection circuit is one, so that for controlling the driving and stopping of the inverter needs just one terminal is required for receiving the output of the combining circuit. Moreover, because the over-current protection circuit is formed of hardware, the protection can be performed at a high speed.

Abstract: In a method for determining the rotor position of a three-phase machine without using a rotary encoder, and to a device for controlling a three-phase motor without using a rotary encoder, the three-phase machine is fed by a converter that can be operated by pulse-width modulation, and the converter has model variables for the rotor angle and the current indicator of the three-phase machine, and the converter has device(s) by using which, in control operation, at least two values are measured which represent a measure of the local inductances of the machine which represent a measure of the local inductances of the machine, the error of the model rotor angle is determined in that, depending on the model rotor angle and the model current indicator, at least two weighting factors are determined, and in that a weighted sum is formed from the at least two measured values and the at least two weighting factors, and in that a further offset value is substracted from the sum, which is likewise determined on the basis

Abstract: A trigger assembly, for use with a power tool having an electric motor, includes a trigger, a conductor coupled for movement with the trigger, and a printed circuit board. The printed circuit board has an inductive sensor thereon responsive to relative movement between the conductor and the inductive sensor caused by movement of the trigger. An output of the inductive sensor is used to activate the electric motor.

Abstract: A technique controls regenerative braking to reduce skidding of a vehicle. Such a technique involves imparting rotation to an alternating current (AC) electric motor to move the vehicle to a first commanded vehicle speed; applying a regenerative braking power to the AC electric motor to bring the vehicle to a second commanded vehicle speed; while applying the regenerative braking power, adjusting the level of regenerative braking power applied to follow a predetermined speed reduction rate; while adjusting the level of regenerative braking power applied, provide a limit to the maximum level of regenerative braking power available; and while providing the limit to the maximum level of regenerative braking power available, adjusting the limit to the maximum level of regenerative braking power available based on a current speed of the vehicle.