10 results about "Switching frequency" patented technology

The invention discloses an electric automobile and an electric current loop control method and device for a permanent magnet synchronous motor of the electric automobile. The method includes the following steps that traveling working condition information of the electric automobile, the d-axis given current and the q-axis given current of the permanent magnet synchronous motor and the d-axis actual current and the q-axis actual current of the permanent magnet synchronous motor are obtained; according to traveling working condition information and a preset neural network algorithm, a d-axis proportionality coefficient, a d-axis integral coefficient, a q-axis proportionality coefficient, a q-axis integral coefficient and the PWM switching frequency are calculated; and the d-axis voltage is calculated according to the d-axis given current, the d-axis actual current, the d-axis proportionality coefficient, the d-axis integral coefficient and a d-axis current PI control algorithm, the q-axis voltage is calculated according to the q-axis given current, the q-axis actual current, the q-axis proportionality coefficient, the q-axis integral coefficient and a q-axis current PI control algorithm, and therefore vector control can be conducted on the permanent magnet synchronous motor according to the d-axis voltage, the q-axis voltage and the PWM switching frequency. Therefore, through setting of control parameters matched with the traveling working condition, the better rapid respond capacity is achieved, and overshooting is reduced.

A resonant gate drive circuit provides efficient switching of, for example, MOSFETs. However, the operation of resonant gate drive circuits often does not allow applications where high switching frequencies are required. According to the invention, a precharging of the inductance of the resonant gate drive circuit is performed. This allows highly efficient and fast MOSFET operation.

The power supply includes parts: power end, high voltage circuit (HVC) connected to the power end, first logic control circuit in use for controlling and driving HVC, the filament circuit (FC) with its input end being connected to the power end, and second logic control circuit in use for controlling and driving FC. The method includes steps: variable frequency control is adopted in the power portion in high voltage; adjusting switching frequency adjusts the input power; using voltage feed forward ensures stable output power approximately when the voltage of input power source changes; half bridge circuit (HBC) or single tube circuit (STC) is adopted in FC; the on time of one switch tube in HBC is fixed, and the on time of the other switch tube is varied with feed back. Main circuit decides the turn off time of STC, and turn on time is controlled by feedback. Scheme of separating FC from HVC possesses high adaptability to magnetron, single tube adopted in HVC so as to lower cost.

A circuit for controlling the switching frequency of an oscillator for a PWM controller for a switching mode power supply, comprising a first stage providing a signal which is related to the temperature of the controller for the switching mode power supply; and an oscillator having an oscillation frequency and being responsive to the signal from the first stage for changing the oscillation frequency such that the oscillation frequency decreases as the temperature increases and vice versa.

The invention discloses a modulation and voltage stabilization control method suitable for a single-power binary hybrid cascaded H-bridge multilevel inverter. In modulation, a modulated wave vm obtained through taking an absolute value of a sinusoidal modulated wave vref is compared with triangular carriers vca, vcb', vcr1' and vcr2' and a voltage constant value 2E to obtain five logic pulse signals A, B, R1, R2 and P; the sinusoidal modulated wave vref is compared with zero voltage to obtain a polar pulse signal D; and an optimized PWM drive signal is generated from the logic pulse signals and the polar pulse signal through a drive logic operational circuit. In voltage stabilization control, real-time adjustment is carried out on amplitudes of triangular carriers vcb, vcr1 and vcr2 through a signal obtained through operation of DC side voltage sampling signals Vdc1 and Vdc2 and voltage reference signals Vdc1* and Vdc2* of auxiliary units, thereby achieving voltage stabilization control on the auxiliary units through combining modulation. According to the control method disclosed by the invention, the stability of capacitor voltage can be controlled, output levels and the equivalent switching frequency of output voltage of the inverter can be improved and the output characteristics of a system are improved.

The invention discloses a signal output and detection precision optimization system. The system comprises a power supply management chip, a hardware low-pass filter, a DMA list module, a software filter, a voltage control module and an acquisition module, wherein the hardware low-pass filter is used for filtering out specific switching frequency and clutters so as to reduce voltage fluctuation reaching an acquisition port; the DMA list module is used for executing DMA data sampling and storing real-time acquired data; the software filter is used for carrying out peak value plus mean value filtering processing on data stored in the DMA list module; the voltage control module is used for carrying out power supply regulation and control on the power supply management chip according to a processing result of the software filter, and the acquisition module is used for processing the processing result of the software filter as data to be uploaded. According to the invention, required outputvoltage, high-precision voltage output and high-precision current acquisition can be rapidly adjusted.