失超保护系统中固态开关的均流控制

失超保护系统在超导托卡马克的运行中发挥着重要作用，其在失超发生时快速转移储存在线圈中的磁场能量，从而保护超导磁体。由于失超保护系统功率较大，在应用时必须并联多个固态开关模块，因此带来的均流问题也有待进一步的解决。本文在选定IGBT作为失超保护系统中的固态开关后，分析了影响其均流的因素，采用调节栅极电阻的方式进行IGBT关断时的动态均流，并对栅极电压进行PI控制以实现IGBT导通时的静态均流，仿真和实验结果均证明了220A电流下该控制方案的有效性。相比于传统支路串入阻抗的均流手段，该方案无须改变主回路，控制方式简单，灵活性更好，同时能有效抵御干扰的影响，进一步推动了固态开关在失超保护系统中的实际应用。

Current sharing control of solid state switch in quench protection system

Quench protection system plays an important role in the operation of superconducting tokamak. When quench occurs, it quickly transfers the magnetic field energy stored in the coil to protect the superconducting magnet. Due to the high power of quench protection system, multiple solid-state switch modules must be connected in parallel, so the current sharing problem needs to be further solved. After selecting IGBT as the solid-state switch in the quench protection system, this paper analyzes the factors affecting its current sharing. The dynamic current sharing when IGBT is turned off is carried out by adjusting the grid resistance, and the static current sharing is realized by PI control of the grid voltage. The simulation and experimental results show the effectiveness of the control scheme at 220A current. Compared with the current sharing method of traditional branch series impedance, this scheme does not need to change the main circuit, with simple control mode and better flexibility. At the same time, it can effectively resist the influence of interference, and further promote the practical application of solid-state switch in quench protection system.