Motor dynamic braking circuit and motor dynamic braking method

Abstract

The invention discloses a motor dynamic braking circuit and a motor dynamic braking method. After being rectified by a rectifier bridge module, alternating current is converted into direct current busP / N with stable voltage through bus capacitor filtering, and then the direct current is converted into the alternating current through an inverter bridge module to drive the motor; one end of a power-on soft start module is connected to the bus positive P, the other end is connected with one ends of a bus capacitor module and a regenerative braking module, the other ends of the bus capacitor module and the regenerative braking module are connected to the bus negative N, and a dynamic braking module is directly connected to the direct current bus P / N. The dynamic braking circuit completely multiplexes the body diodes of the inverter bridge module to achieve rectification, three additional diodes do not need to be additionally arranged on each axis, the system cost is reduced, and the PCB area is reduced; the dynamic braking module shared by the multi-axis common bus system can be supported without adding any additional wiring, so that the system wiring is simplified, and the cost of wiring terminals and cables is reduced.

Description

technical field [0001] The invention relates to a motor dynamic braking circuit and a motor dynamic braking method. Background technique [0002] Dynamic braking is widely used in motor-driven power electronic conversion equipment. When an emergency alarm occurs in the system, or the system is powered off, or the system needs to be stopped in an emergency, the dynamic braking will work, and the motor will be stopped quickly and safely to avoid causing damage. Equipment damage, personal injury, etc. Several common topologies for dynamic braking are as follows: [0003] Japanese patent document JP3863529B2 discloses a dynamic braking topology diagram, which is also the most simple and common dynamic braking topology. When receiving a dynamic braking demand, the system stops PWM transmission, then starts the dynamic braking circuit, pulls in the relay, and The energy in the motor windings is dissipated in the resistive loop, stopping the motor quickly. In the case of low-pow...

AI Technical Summary

Problems solved by technology

In the traditional system, the dynamic braking module can only be placed on the AC side. If it is placed on the DC side, the terminal voltage of the dynamic braking module will be clamped by the bus capacitor voltage, and the dynamic braking effect will be greatly affected. The dynamic resistor also bears the additional discharge of the bus capacitance energy, which increases the resistance burden

Images