高压直流输电换相失败响应策略与预测控制技术路线分析

摘要

From the principle of extinction angle control used in HVDC, the advantage and shortage of extinction angle control based on actual measuring and predictive calculation are contrasted. And the response strategies of commutation failure based on the Siemens and ABB technology are discussed from control and protection system. The response of commutation failure prediction control function (CFPREV) under AC voltage falling and distortion fault are focused. The results of simulation show that, when AC voltage falls seriously, the CFPREV cannot prevent commutation failure, but the CFPREV is in the favour of the restoration of DC system after commutation failure;when the electrical relation between DC and AC system is strong or the distortion degree of AC voltage is low, the CFPREV function has obvious effect on preventing commutation failure.%从高压直流输电熄弧角控制的原理出发，对比了实测型和预测型熄弧角控制方式的优缺点，从控制系统响应和保护系统响应两方面探讨了SIEMENS和ABB所采取的换相失败响应策略。着重研究了换相失败预测控制功能（CFPREV）在不同交流母线电压跌落程度和电压畸变程度故障下的响应情况。仿真结果表明，当交流母线电压跌落较为严重时，无论是否投入CFPREV功能，都未能阻止换相失败，但投入CFPREV功能后有利于换相失败后直流系统恢复；当直流系统与交流母线间的电气联系较强或交流母线电压畸变程度较低时，CFPREV功能在预防换相失败上有明显效果。