变拓扑混合双12脉波整流器的电流预测控制

Hybrid dual twelve-pulse flexible-topology thyristor rectifier with predictive current control

多脉波整流技术是大功率整流系统抑制谐波电流的主要手段之一,传统的24脉波整流器串联工作时存在网侧谐波电流过高的缺陷。为此,对传统24脉波整流器进行改造,通过增加若干切换开关,得到一种具有混合工作模式的变拓扑双12脉波整流器。研究了开关状态的不同组合与串联、并联和冗余工作模式的对应关系,详细分析了混合工作模式的等效电路和电流预测控制的实现机理,进一步研究了电流预测控制策略实现不同工作模式间的快速切换和输出电流的快速响应问题。最后,通过仿真分析和实验验证了电流预测控制策略的有效性,结果表明在相同负载电压下,混合模式的网侧谐波电流低于串联模式。

Multi-pulse rectifying technology is one of the main solutions to suppress the grid-side harmonic current in high-power rectifier system.However,conventional 24-pulse thyristor rectifier has the disadvantage of high harmonic injections when it is operated in series mode.The traditional 24-pulse rectifier was modified by adding some switches,and a hybrid dual twelve-pulse flexible-topology thyristor rectifier(HDTPFTTR)with hybrid operating mode was obtained.Relationship between different combination states of the auxiliary switches and its equivalent series,parallel as well as redundant operating modes was studied.Then the equivalent topology of the hybrid mode as well as the predictive current control based on HDTPFTTR was discussed in detail.Furthermore,the implementation of the control strategy for swift switching among different operating modes and fast current responses was analyzed.Finally,the feasibility of the proposed HDTPFTTR with the predictive current control strategy was verified through simulation and experiments.Results show that the predictive current control strategy can track the load current rapidly.Moreover,the total harmonic distortion(THD)value of the input current in hybrid mode is lower than that of the series mode under the same load voltage.