固态断路器多IGBT串联混合均压电路设计

固态断路器需多IGBT串联切断短路故障电流，针对多IGBT存在电压分配不均、局部电压过高、损耗大等问题，提出一种混合式均压控制电路拓扑结构。分析固态断路器多IGBT均压影响因素，研究均压拓扑性能。优化缓冲电路结构，改进充放电型缓冲电路，减小损耗；引入双阈值钳位控制电路，改善IGBT过电压；提出被动均压与辅助反馈主动均压结合的混合均压控制策略，加快响应速度，实现均压动态自适应调节。制作样机，进行固态断路器设计拓扑和控制的仿真及实验验证，结果表明：混合式均压控制电路可减小IGBT电路超调量，具备更强的抑制过电压能力，提升响应速度。

Solid state circuit breaker with multi-IGBT series hybrid balancing voltage circuit design

Solid-state circuit breakers require multiple IGBT in series to cut off the short-circuit fault current, and a hybrid voltage-balancing control circuit topology is proposed to address the problems of uneven voltage distribution, high local voltage, and high loss of multiple IGBTs. Analyze the influence factors of voltage equalization of multiple IGBTs in solid-state circuit breaker, and study the performance of voltage balance topology. Optimize the buffer circuit structure, improve the charging and discharging buffer circuits, and reduce the loss; introduce the dual-threshold clamp control circuit to improve the IGBT over-voltage; and propose a hybrid balancing voltage control strategy that combines the passive voltage equalization and the auxiliary feedback active voltage equalization, which accelerates the response speed and achieves the dynamic adaptive regulation of voltage equalization. The prototype is fabricated, and the simulation and experimental verification of the solid-state circuit breaker design topology and control are carried out, and the results show that the hybrid balancing voltage control circuit can reduce the over-regulation of the IGBT circuit, have stronger over-voltage suppression capability, and improve the response speed.