固态限流器对双端电源系统正常运行的影响

Impact of Solid State Fault Current Limiter on Double-source Systems

详细分析了新型固态限流器对单机-无穷大系统启动暂态过程和稳态运行的影响,得出以下结论:启动过程中限流器直流电感的充磁使线路电流上升减慢;耦合变压器漏抗和桥路损耗等影响发电机功角和励磁电压;直流限流电感(电抗)与单机-无穷大系统联线阻抗之比越小,其启动充磁对系统的影响越小;耦合变压器漏抗越低,对系统稳态运行影响越小。分析和仿真均验证了直流电感按限流要求设计时,固态限流器对系统的运行没有明显影响,若采用低漏抗耦合变压器或带旁路电感则可进一步降低这种影响。

The starting transient and steady state of solid state fault current limiter （SSFCL） incorporated into one-machine infinite-bus system is discussed in details. The charging transient of DC reactor slows the rising rate of line current, and the leakage reactance of the series-coupling transformer and loss of SCR bridge affect the generator load angle and excitation voltage. The smaller the ratio of DC inductance and the system tie-impedance is, the slighter the starting transient impact is, and the lower the coupling transformer leakage reactance, the smaller the influence on the steady state operation. With the designed current-limiting DC inductance, SSFCL has no obvious influence on system operation, and with low leakage reactance coupling transformer or bypass AC inductance, that influence can be even much smaller. All those are confirmed by analysis and simulation.