功率硬件在环仿真中功率接口直流电压控制及电容参数设计

作为功率硬件在环(PHIL)仿真中连接数字侧和物理侧仿真的互联装置,功率接口对PHIL仿真系统的稳定性起决定性作用。物理侧负载扰动所引起的直流电压波动是影响功率接口的稳定运行的关键问题之一。针对这一问题,为了提高PHIL仿真系统稳定性,考虑控制时滞,提出一种基于直流输出电流前馈的直流电压改进控制策略,并给出了其前馈系数的参数设计方法。根据变流器交直流侧有功功率平衡关系,利用小信号分析方法,建立了功率接口交直流统一模型,通过该模型分析并证明了所提控制策略在负载小扰动情况下抑制直流电压波动的有效性。提出一种直流电容参数计算方法,并证明前馈控制可以有效地减少直流电容。最后,仿真和实验验证了所提方法的有效性。

DC Voltage Control and Capacitor Parameter Design of Power Interface in Power Hardware-in-the-loop Simulation

As the interconnecting device connected digital simulation and physical equipment in power hardware-in-the-loop(PHIL), power interface plays a decisive role in the PHIL simulation system. The DC voltage fluctuation caused by load disturbance on the physical side is one of the key problems of running a stable power interface. For this problem, in order to improve PHIL system stability, a DC voltage optimum control strategy based on current feed-forward control considering control delay and its feed-forward control parameters are given. According to active power balance of AC-DC converter side, a unified power interface AC-DC model is developed using the small signal analysis method. The effectiveness of the proposed control strategy is proved to inhibit DC voltage fluctuations in the case of small disturbance. A DC capacitance parameter calculating method is presented and the feed-forward control is proved effective in reducing the DC capacitance. Finally, simulations and experiments verify the effectiveness of the method. This work is supported by National Natural Science Foundation of China(No. 51277137).