以提高多端电压源型直流输电系统的运行可靠性为目的,提出了基于直流电压—有功功率调节特性的多端直流输电系统控制策略。在系统负荷发生突变或任一换流站故障退出后,所有具备功率调节能力的换流站根据给定的调制方式在一定程度上分担系统功率的缺额,这样既维持了系统内的功率平衡,又避免了单个换流站承担功率过大的情况。最后通过数字仿真验证了所提出的控制策略设计的正确性和可行性。
To improve the operation reliability of the direct current transmission system with multi-infeed voltage source converter (VSC) stations, a control strategy based on dc voltage and active power regulation characteristics for VSC stations is proposed. Based on the proposed control strategy, all VSC stations with power regulating capability will output power accordingly when the system load is suddenly changed or one of the VSC stations falls down. Thus the system will remain stable while there is no overloading for an individual station. Simulation results show that the control strategy proposed is effective in improving the operation reliability of the multi-infeed VSC system.