电压不对称条件下并联电压源型SMES的触发方式

CONTROL SCHEME OF VOLTAGE TYPE SUPERCONDUCTING MAGNETIC ENERGY STORAGE (SMES) UNDER ASYMMETRICAL VOLTAGE

电压不对称条件下超导磁储能 (SMES)的触发控制一直是个值得关注的问题。对称触发的SMES会向系统注入负序电流及以二倍频波动的功率。目前关于电压源型变换器不对称触发控制都是以消除负序注入电流为控制目标。文中在详细阐述不对称触发的研究背景的基础上 ,提出了可以消除有功功率二倍频波动的不对称触发。仿真计算结果表明 ,采用不对称触发后 ,SMES向系统注入的有功功率的平均值接近于系统的有功功率需求 ,二倍频分量幅值也明显降低。

Control scheme of superconducting magnetic energy storage (SMES) is very important if system voltage is asymmetrical. SMES transfers the 2nd harmonic power and the negative sequence current into the system under such cases if asymmetrical control is used. However, the 2nd harmonic power may amplify power unbalance and destroy system stability. Two asymmetrical control methods which aim at eliminating the 2nd harmonic power are proposed. Comparison of these two methods is discussed. Simulation results show that the fluctuation of power transfer into system is depressed with the proposed asymmetrical control scheme.