模块化级联型SMES变流器及其总分式功率无源控制策略

为实现超导磁储能系统(SMES)的大规模可扩展式应用,提高控制系统的动态性能和鲁棒性,改进级联型SMES变流器的电路拓扑,并设计基于无源控制器的总分式功率控制策略。采用二阶广义积分构造虚拟轴,实现单相电路的坐标变换;证明了无源系统反馈互联后仍保持端口受控哈密尔顿模型结构的特征,分别在交、直流侧设计控制策略,降低了控制设计的复杂度;提出总分式功率控制策略,实现系统并网总功率和各级联模块分功率的独立控制;分别在交、直流侧设计无源控制器,提高了系统控制的动态性能和稳定性。仿真分析验证了模块化级联型SMES变流器及其总分式功率无源控制策略的有效性。系统具备模块化特征,可实现灵活扩展以及各超导磁体功率的独立控制,并具有更快的响应速度、更小的超调量和更好的并网电流质量。

Modular cascaded SMES converter and its total fraction passivity-based power control strategy

In order to realize the large-scale scalable application of SMES(Superconducting Magnetic Energy storage System) and improve the dynamic performance and robustness of the control system, the circuit topology of cascaded SMES converter is improved, and the total fraction power control strategy based on passivity-based controller is designed. The second-order generalized integrator is used to construct the virtual axis to realize the coordinate transformation of the single-phase circuit. It is proved that the passive system maintains the characteristics of the port-controlled Hamilton model structure after the feedback interconnection. Therefore, the control strategy is designed at the AC and DC sides respectively, which reduces the complexity of the control design. The total fraction power control strategy is proposed to realize the independent control of the total system power and the power of each module. The total fraction power control strategy is proposed to realize the independent control of the total system power and the power of each module. The passivity-based controllers are designed at the AC and DC sides respectively to improve the dynamic performance and stability of the system control. Simulation analysis verifies the effectiveness of the cascaded SMES converter and its total fraction passivity-based control strategy. The modularity of the system allows flexible expansion and independent control of the power of each superconducting magnet with faster response speed, smaller overshoot and better grid-connected current quality.