Research on the integrated braking energy recovery strategy based on supercapacitor energy storage for AC-DC-AC variable-frequency drive

The AC-DC-AC variable-frequency drive system has been widely used in industrial and agricultural production. Most of them adopt the energy consumption brake, which leads to large energy waste. The supercapacitor based energy saving system can absorb the braking energy when motor decelerates, which achieves energy saving. However, this system has shortcomings, such as the large energy storage capacity configuration and it is expensive, which restricts its application. In this paper, an integrated braking energy recovery method and an optimal configuration method were proposed with the goal to improve the performance price ratio of the overall braking energy recovery system, and the coordinated control strategy without communication lines among the variable-frequency drive, the energy storage unit and the braking resistor was designed. Design examples on drilling rig and simulation results verify the correctness and validity of the proposed method. © 2014 Chin. Soc. for Elec. Eng.