摘要
针对传统两电平逆变器与三电平逆变器所需要的开关数量多、损耗大的问题,采用T型逆变器不仅可以克服传统多电平逆变器的缺点,还可提高系统的效率,将Z源网络用于T型逆变器提升了逆变器直流侧的电压水平。为此,将准Z源T型逆变器拓扑结构应用于P-Q并网控制系统中,其中P-Q控制器的电流控制环采用准比例谐振(quasi proportional resonant,qPR)控制策略,实现对电流的无静差跟踪,从而更好地控制并网系统有功与无功的输出。最后,通过MATLAB/Simulink软件仿真实验和实际硬件样机试验验证改进P-Q控制策略的光伏准Z源逆变器并网系统的可行性和有效性。相比于传统的双闭环控制策略,所提出的改进P-Q控制策略可以降低逆变器输出电流谐波,提高系统的经济性;相比于控制器电流环采用比例-积分(proportion integration,PI)控制,所采用的qPR控制能够更好实现对电流与功率的追踪,提高系统的稳定性。
To solve problems for numbers of switches and large losses of traditional two-level inverters and three-level inverters, it is able to overcome shortages of traditional multi-level inverters and improving efficiency of the system by using the T- type inverter as well as promoting voltage level at the DC side of the inverter by using Z-source network for the T-type inverter. Therefore, the paper applies topology of the quasi-Z-source T-type inverter to the P-Q grid-connected control system. Current control loop of the P-Q controller adopts a kind of quasi proportional resonant （qPR） control strategy to realize tracking without static error for current and better control active power output and reactive power output of the grid-con- nected system. Finally, Matlab/Simulink simulation experiment and prototype testing on actual hardware has verified feasi- bility and effectiveness of the grid-connected system of photovoltaic quasi-Z-source inverter with improved P-Q control strategy. Compared with traditional double closed-loop control strategies, the proposed improved P-Q control strategy could reduce output current harmonic of the inverter and improve economy of the system. Compared with quasi proportion integration （qPI） control by current loop of the controller, the q-PR control could better realize tracking for current and power and improve stability of the system.
作者
程启明
李涛
程尹曼
孙伟莎
陈路
CHENG Qiming;LI Tao;CHENG Yinman;SUN Weisha;CHEN Lu(Shanghai Key Laboratory Power Station Automation Technology Laboratory,Shanghai University of Electric Power,Shanghai 200090,China;North Power Supply Branch,State Grid Shanghai Electric Power Company,Shanghai 200041,China)
出处
《广东电力》
2018年第9期54-61,共8页
Guangdong Electric Power
基金
国家自然科学基金项目(61573239)
上海市重点科技攻关计划项目(14110500700)
上海市自然科学基金项目(15ZR1418600)
上海市电站自动化技术重点实验室项目(13DZ2273800)
