摘要
静止无功发生器(STATCOM)在稳定接入点电压时,常采用双环控制法,但该方法存在多个PI调节器,难以实现,同时也没有考虑电网电压三相不平衡的问题。本文采用瞬时功率平衡原理,将参考电流信号直接变换为参考电压信号,省去了传统双环控制中的电流内环PI调节器,同时引入负序电压前馈环节以维持接入点电压保持三相平衡,并推导了负序电压情况下逆变器输出电压和输出电流之间的代数关系式。考虑到瞬时功率平衡原理需要STATCOM的等效电阻和等效电感值,而这两个参数值一般难以精确测量,为此根据反馈信息不断修正这两个参数的测量值。仿真分析和试验结果表明,所提出的控制方法在稳定接入点电压的同时,能有效维持接入点电压三相平衡。
The STATCOM often adopts double loop control method to regulate the voltage of the common coupling point（PCC）. But this method exists multi-PI-adjusters, and so is difficult to realize. At the same time, this method doesn’t consider the problem of unbalanced three phase voltage. Therefore, a novel control method is proposed in this paper. The novel method adopts the theory of instantaneous power balance to change the current reference signal to voltage reference signal directly, and so get rid of the PI adjusters in inner loop of traditional double loop control method. Furthermore, The novel method imports negative sequence feed forward control loop to compensate the unbalanced three phase voltage. With a view to that the theory of instantaneous power balance requires the value of equivalent resistance and equivalent inductance of STATCOM, but the parameters value is difficult to measure, so a method to modify the measure value of the parameters is put forward in this paper. Simulation and experimental results show that the proposed method can not only stabilize the PCC voltage, but also maintain the balance of the he PCC voltage.
出处
《电工技术学报》
EI
CSCD
北大核心
2010年第3期138-143,共6页
Transactions of China Electrotechnical Society
基金
国家自然科学基金资助项目(50907017)
