Motor bus voltage sampling circuit based on CCM working mode Flyback circuit

Abstract

The invention discloses a motor bus voltage sampling circuit based on a CCM working mode Flyback circuit. The motor bus voltage sampling circuit based on the CCM working mode Flyback circuit includesa Flyback unit and a sampling unit; the Flyback unit includes a DC/DC main chip, a power conversion loop, and a constant resistive load; the primary side of a power conversion transformer is connectedto a film capacitor of the motor bus, and the secondary side is connected to the resistive load; the DC/DC main chip inputs a driving PWM signal to the power conversion transformer; the sampling unitincludes an MCU controller and a signal sampling circuit; and the MCU controller collects the power conversion transformer output voltage through the signal sampling circuit and a duty cycle D parameter of the driving PWM signal provided by the DC/DC main chip, thereby calculating the motor bus voltage. The motor bus voltage sampling circuit based on the CCM working mode Flyback circuit fully utilizes an emergency power supply discharge circuit of a motor controller, and fully utilizes the sampling of a low voltage signal, so as to indirectly test the bus voltage; therefore, the fast responseof the sampling circuit is ensured, the interference of the high-voltage side is not introduced, and the cost of the high-voltage devices can be saved.

Description

technical field [0001] The invention belongs to the field of new energy vehicles, in particular to a motor busbar voltage sampling circuit based on a CCM working mode Flyback circuit Background technique [0002] With the rapid development of automotive electronics, new energy vehicles have developed rapidly in recent years; this has higher requirements for the safety and reliability of vehicles. The advanced control strategy of motor is the basis of automobile safety and reliability. Due to the requirements of the advanced control strategy of the automotive electronic controller, it is necessary to sample the voltage of the film capacitor of the driver; this can effectively and timely monitor the voltage of the film capacitor, ensure the effective control and manipulation performance of the motor, and at the same time ensure that the bus computer safety. This patent combines the basic needs of automobiles and functional safety requirements, and designs an indirect samplin...

AI Technical Summary

Problems solved by technology

[0006] Using resistor divider to directly detect bus voltage also has several defects: 1. Need to use high-voltage and high-precision

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