Dual-carrier svpwm control method for suppressing the circulation of energy feedback device

Abstract

The invention discloses a dual-carrier SVPWM control method for inhibiting the circulation of an energy feedback device. The dual-carrier SVPWM control method comprises the following steps: segmenting, calculating and judging sectors, calculating a voltage vector acting time, calculating a voltage vector switching time, performing three-phase carrier judgment and generating PWM waves. According to the dual-carrier SVPWM control method disclosed by the invention, the energy feedback device collaboratively used by a general purpose converter is controlled by using the SVPWM control technology, a new dual-carrier space vector modulation technology is applied to the control strategy of the energy feedback device, the circulation during the parallel operation of the energy feedback device and a rectifier bridge of the converter can be effectively reduced, the output current waveform distortion is reduced, and the efficiency and the stability of the whole system are improved.

Description

technical field [0001] The invention relates to the technical field of power electronics, in particular to a SVPWM control method of a frequency converter energy feedback device. Background technique [0002] The inverter energy feedback device is a special grid-connected inverter. Its DC input side is connected to the DC bus of the inverter, and its AC output side is connected to the input side of the inverter, and is connected to the three-phase grid. When the motor driven by the inverter works in the regenerative braking state, the regenerative braking energy of the motor enters the DC bus of the inverter, causing the DC side voltage of the inverter to rise. When the voltage reaches a certain set value, By controlling the turn-on and turn-off of the six power devices of the energy feedback device, the energy on the DC bus is fed back to the power grid to realize the recycling of electric energy and achieve the purpose of energy saving. [0003] SVPWM is a control method ...

AI Technical Summary

Problems solved by technology

[0005] Since the energy feedback device and the rectifier bridge of the inverter are in parallel topology, if the traditional single-carrier SVPWM switching modulation mode is adopted, the theoretical analysis shows that since there are two zero vectors in the switch state, the energy feedback device During operation, pulse current will be generated on the input side of the inverter, which will cause a circulation problem, reduce system efficiency, and also affect the grid-connected current quality of the energy feedback device

Although the output filter with large inductance can suppress the circulating current, it will inevitably increase the size and cost of the energy feedback device

Therefore, adopting the traditional SVPWM control strategy will not be conducive to the efficient and stable operation of the energy feedback device

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