A current control method and a motor control circuit are provided. The motor control circuit includes a first rectification circuit and a second rectification circuit connected in parallel between a live wire and a natural wire of a power supply, a sampling resistor, and a controller connected to the second rectification circuit. The first rectification circuit is connected to the motor. The current control method include obtaining a periodic waveform signal of a bus voltage; collecting a bus current value through the sampling resistor; sampling the periodic waveform signal for a plurality of times; linearly fitting multiple voltage values obtained at a plurality of sampling time points to obtain multiple slopes; obtaining a power frequency according to the multiple slopes; calculating a compensation current value according to the power frequency; and generating a control signal according to the compensation current value and the bus current value.

A motor drive system is presented. The motor drive system may be configured to output a first, a second, and a third drive signal for driving an electric motor. The motor drive system may comprise a first power converter configured to generate the first drive signal, and a second power converter configured to generate the second drive signal. The motor drive system may comprise a third power converter configured to generate the third drive signal. Some or all of the power converters may be implemented as synchronous buck power converters.

A motor control method and a motor control circuit. The motor control method includes: collecting a real-time current waveform of an AC power supply through a sampling circuit; obtaining a periodic voltage waveform signal of the AC power supply through a rectification circuit; obtaining a power frequency of the AC power supply by sampling the periodic voltage waveform signal multiple times; compensating the real-time current waveform and generating a target current waveform according to the power frequency; and controlling the motor according to the target current waveform. The rectification circuit includes: a first rectification circuit, a second rectification circuit, and a target capacitor; the first rectification circuit and the second rectification circuit are connected in parallel to two output ends of the AC power supply and configured to rectify the AC power supply; a controller is connected to an output end of the second rectification circuit.

A motor control device 50 controls a drive motor 60 connected with an opening and closing body 13 of a vehicle 10 and provided for automatically opening and closing the opening and closing body 13. The motor control device includes: an output detection unit 514, detecting an output of the drive motor 60 in accordance with an operation state of the opening and closing body 13; and a mode switching unit 518, switching a control mode of the drive motor 60 to a sine wave drive mode or a rectangular wave drive mode based on a judgment value obtained from an output result of the output detection unit 514.

A method for operating a position-sensorless BLDC motor of an oil pump (19) is proposed. When the oil pump (19) is put into operation and run up to speed, to warm an oil that is transported by the oil pump (19), the BLDC motor is operated in a pre-controlled-excited mode until the oil has a kinematic viscosity that allows the BLDC motor to be operated in a controlled mode above a motor-specific limiting speed of a rotor of the BLDC motor. Waste heat of the BLDC motor generated by the pre-control is in this case dissipated to the oil in the surrounding area of the oil pump (19).

This pre-control is intermittently interrupted in order to detect a voltage induced by the rotor in the unexcited coils of a stator of the BLDC motor, by means of which a rotor position and a rotor (rotational) speed are determined sufficiently accurately above the limiting speed of the rotor.

Above this limiting speed, once it is detected that it has been exceeded, a changeover is made to a controlled-excited mode of the BLDC motor.

Also proposed are a computer program, a computer program product, a heat-transfer medium system and a vehicle.

A motor driver and method for driving motors with multiple phases, where the motor driving circuit includes a number of switches and a shunt resistor in a shared path of the circuit. The control unit is designed to generate control signals for the switches to produce pulse width modulation signals based on space vector modulation, which alternates between bottom clamping and top clamping across different motor phases; inject zero vectors during clamping transitions from one phase to another, allowing current measurements through the shunt resistor at these transition points for phase current determination; measure the current through the shunt resistor at least twice each cycle; and determine the phase currents from these measurements. The control unit also uses a closed loop control algorithm such that the determined phase currents as feedback for generating control signals for the switches.

A grid-independent micro-combined heat and power system supplies heat and electricity to a building or a small number of buildings and can operate completely independently of a central-type electrical power grid. The system includes a variable speed liquid-cooled engine and a liquid-cooled generator that is configured to output an electrical supply of between approximately between 0.5 kW and 40 kW, a coolant loop, and a water circuit. The coolant loop heats a liquid using claimed heat from the genset to heat water that can be utilized as a domestic hot water source for cooking or cleaning or for a hot water source for heating. The speed of the engine may be controlled to control the output of the genset to meet prevailing electrical loads. The system may be part of a microgrid incorporating several such systems that are in electrical communication with one another and that collectively supply electrical power and heat to from a few buildings to about one hundred buildings.

A planetary magnetic motor and a method of use thereof is disclosed. The planetary magnetic motor may have a stator and one or more planetary rotor systems. The stator may have a shell body with a plurality of winding sets distributed along the inner surface of such shell body. The planetary rotor system may have a sun gear with an output shaft, a plurality of planet gears coupled around the sun gear, and an outer ring gear. Each planet gear may have a permanent magnet attached where the permanent magnet extends inside the shell body of the stator and is proximate and faces the winding sets. An alternating current may be fed to the winding sets that create alternating magnetic fields that interact with the permanent magnets to rotate the planet gears and the planetary rotor system, in general.

A brushless electric motor includes: a stator core, which includes Z tooth groups spaced apart from each other in a first circumferential direction; a rotor, which includes a magnetic ring having P poles, P being an even number; and X phase conductors, which are wound on the tooth groups to form coils, where X2, and Z=PX, wherein in the same phase conductor, the coils on two adjacent tooth groups have opposite winding directions in a second circumferential direction of the tooth groups, and are spaced apart by X1 tooth groups.

A motor driving system and a method for diagnosing a fault thereof are provided. The motor driving system includes a driving unit including a motor, and a first inverter and a second inverter connected to both ends of each of multiple windings, respectively, and a control unit configured to control outputs of the first inverter and the second inverter based on a zero-sequence current command and further configured to diagnose a fault in the driving unit based on a phase current flowing in each of the multiple windings as a result of the control.