37results about How to "Small current ripple" patented technology

A motor driving device and driving method of the same used to surely suppress the influence of counter electromotive force is provided. The motor driving device 100 includes an auto-decay portion 141. The auto-decay portion 141 controls a path of a electric current flow in a motor coil when supplying the electric current and when decaying the electric current. The influence of counter electromotive force generated in a stepping motor 200 can be suppressesed by the auto-decay portion 141 configured to control so that a ratio or an decay time of a slow decay mode and a fast decay mode of previous cycle is different from a ratio or an decay time of the slow decay mode and the fast decay mode of current cycle.

The invention discloses a controller for a digitalized proportional valve with high switching frequency. The controller comprises a microprocessor, a communication port, a drive circuit, a power amplification circuit, a position detection circuit and a circuit detection circuit. The communication port is connected with the microprocessor in a bidirectional communication mode, the position detection circuit and the current detection circuit are connected with analog-digital conversion interfaces of the microprocessor respectively, the microprocessor is connected with the power amplification circuit through the drive circuit, and the power amplification circuit is in electric connection with an electromagnetic coil of the proportional valve. The invention further discloses a control method of the controller for the digitalized proportional valve with high switching frequency. The method comprises the steps that the microprocessor receives a position setting signal and a current setting signal through the communication port, and whether position closed-loop control and current closed-loop control or only the current closed-loop control is adopted in the controller for the proportional valve is judged through a selection switch. By means of the control method, the working modes can be selected according to the actual working demands, and good flexibility and adaptability are achieved.

The invention relates to an electric automobile sliding prevention control method, a device, a system and a storage medium. The state of an electric automobile is monitored and comprises an accelerator signal, a speed signal, a brake signal and a gear signal of the electric automobile. Whether a sliding prevention signal is generated by triggering or not is judged according to the state. A motor of the electric automobile is controlled to work in a speed control mode if the sliding prevention signal is generated, the speed is preset to be 0, the pulse number of backward sliding of the electricautomobile within unit time serves as closed loop feedback, a closed loop preset value is 0, the difference value of the closed loop feedback value and the closed loop preset value is proportionallyadjusted and then overlaid on speed loop output, sliding prevention adjusting time is greatly shortened, and backward sliding distance is shortened.

The invention discloses a wide-voltage-input efficient direct-current power converter for an aerostat. The wide-voltage-input efficient direct-current power converter comprises a SuperBuck circuit, a push-pull circuit, a closed-loop control circuit and a diode used for achieving the series connection of the output end of the SuperBuck circuit and the output end of the push-pull circuit, wherein the SuperBuck circuit is composed of an inductor, a capacitor, a diode and a switch tube, and the push-pull circuit is composed of a switch tube, a boosting transformer, a rectifier diode and a filter capacitor. The wide-voltage-input efficient direct-current power converter for the aerostat has the advantages that the polarity of input voltages and the polarity of output voltages are identical, a main circuit device is simple, input currents and output currents are consecutive, input and output are common-grounded, current pulses caused to a power supply bus and a storage battery are small, and smooth switching of voltage boosting and voltage reduction can be achieved.

The invention relates to a single-stage bridgeless boost Cuk resonant LED drive circuit, comprising a bridgeless boost Cuk circuit unit and an LLC circuit unit, wherein a lower switch tube in the LLC circuit unit and a bridgeless boost Cuk circuit unit The switch tubes share a power switch tube, and the bridgeless boost Cuk circuit and the LLC circuit are integrated into a single-stage AC-DC drive circuit by multiplexing the power switch tube. where the input AC power supply V in , power diode D 1 ~D 6 and D 8 , inductance L 1 , L 2 and L 3 , the intermediate capacitor C 1 and C 2 , bus capacitance C bus , the second power switch tube S 2 Constitute a bridgeless boost Cuk circuit unit; power diode D 7 , D9‑D 12 , Power switch tube S 1 , S 2 , resonant inductance L r , resonant capacitor C r , high frequency transformer T with center tap on secondary side, output capacitor C 0 It constitutes an LLC circuit unit. The invention realizes the bridgeless single-stage PFC circuit and the ZVS soft switching through the multiplexing of the bridgeless boosting Cuk PFC circuit and the LLC circuit switch tube, and reduces the conduction loss and switching loss of the main circuit of the converter.

The invention relates to a disc-type coreless permanent-magnet synchronous motor controller based on a current inverter and a method. The disc-type coreless permanent-magnet synchronous motor controller comprises a control circuit, a three-phase inverting circuit and a step-down chopper circuit, wherein the three-phase inverting circuit is used for driving a disc-type coreless motor, and the signal input end of the three-phase inverting circuit is connected with the signal output end of the control circuit; the control signal input end of the step-down chopper circuit is connected with the signal output end of the control circuit, and the current output end of the step-down chopper circuit is connected with the current input end of the three-phase inverting circuit through an inductor L; the output shaft of the disc-type coreless motor is connected with the signal input end of the control circuit through an angle sensor; and the three-phase current outputs of the three-phase inverting circuit are respectively connected with the signal input end of the control circuit through a current sensor. The controller controls the speed regulation of the disc-type coreless permanent-magnet synchronous motor and increases the maximum speed of the motor. The controller has the characteristics of small current pulsation, good sinusoidal performance, convenience in energy feedback and the like.

The present invention provides a PFC circuit and method for dynamically adjusting the switching frequency, comprising: a PFC control chip, the switching frequency programming pin of the PFC control chip is externally connected with an equivalent resistance R f ; The PFC control chip is grounded based on the ground pin, powered based on the connection between the power supply pin and Vcc, based on the drive signal output pin and the gate gate of the power switching device of the PFC circuit; the equivalent resistance R f by the first fixed resistor R 1 , the second fixed resistor R 1 and PTC resistor R PTC composition, the equivalent resistance R f The resistance is the PTC resistor R PTC The resistance value is determined by the temperature of the power switching device. The invention is used to protect the power switching device of the PFC circuit. At light load, the switching frequency is increased, and the current ripple in the switching cycle is reduced, thereby reducing the current ripple rate, improving the current ripple, and reducing EMC noise. According to the temperature rise of the power switch device, the switching frequency of the power switch device is dynamically reduced in real time, the switching loss is reduced, the temperature rise is reduced, and the life of the power switch device is improved.