自同步电压源永磁直驱风电机组的直流电压同步机制及其统一控制结构  

Synchronization Mechanism and Unified Control Structure for PMSG-based WTGs by Using the DC-link Voltage to Realize Self-synchronous Voltage Source Control

作　　者：秦垚 王晗[1] 邓桢彦 周党生 张建文[1] 蔡旭[1] QIN Yao;WANG Han;DENG Zhenyan;ZHOU Dangsheng;ZHANG Jianwen;CAI Xu(Key Laboratory of Control of Power Transmission and conversion,Ministry of Education,Shanghai Jiao Tong University,Shanghai 200240,China;Shenzhen Hewang Electric Co.,Ltd.,Shenzhen 518055,China)

机构地区：[1]上海交通大学电力传输与功率变换控制教育部重点实验室,上海200240 [2]深圳市禾望电气股份有限公司,深圳518055

出　　处：《高电压技术》2023年第1期31-41,共11页High Voltage Engineering

基　　金：国家电网有限公司科技项目(5100-202040462A-0-0-00)。

摘　　要：新型电力系统呈现出新能源高比例渗透和电力电子装置高比例接入的“双高”特点,电压源控制是提高“双高”电网下风电机组并网稳定运行的有效方法。基于并网变换器直流电压同步并网的控制方法可有效实现永磁直驱风电机组的自同步电压源控制,但该控制方法下存在直流电压无法维持在设定值的问题。为解决上述问题,提出一种新型直流电压同步控制方法,在电网频率变化时控制直流电压始终维持在设定值,且使同步控制器的输出频率保留实时映射电网频率变化的特点。详细阐明了所提控制方法的同步机制,揭示了其与现有2种直流电压同步控制方法之间的本质联系与区别;在此基础上,提出上述3种直流电压同步控制方法的统一控制结构,并利用频域分析法对3种同步控制方法的动态特性、抗扰性以及阻尼特性进行了对比分析。搭建了2 MW永磁直驱风电机组的仿真模型和硬件在环实验平台,仿真和实验结果表明,所提的直流电压同步控制方法在直流电压维持恒定的前提下,同步频率可以准确实时映射电网频率变化,且扰动项对同步频率的影响不超过0.5%。New power system is characterized by high penetration of renewable energy sources and high proportion of power electronics(namely, double-high). The voltage source control is an effective method to improve the grid-connected stability of wind turbine generators(WTGs) in the “double-high” grid. The control method based on the DC-link voltage of the grid-connected converter can be adopted to effectively realize the voltage source control for PMSG-based WTGs.However, there is a disadvantage that the DC-link voltage cannot be maintained at the set value. To address the above problems, a novel DC-link voltage synchronization control method is proposed, which can control the DC-link voltage to always maintain at the set value, and the output frequency of the synchronization controller retains the feature of real-time mapping of the grid frequency. The grid synchronization mechanism of the proposed control method is elucidated in detail,and the intrinsic connection and difference between the proposed control method and the two existing DC-link voltage synchronization control methods are revealed, based on which the unified control structure is established. Then the dynamic response characteristics, anti-disturbance performance, and damping characteristics are compared and analyzed by using frequency domain analysis. The simulation model and hardware-in-loop experimental platform of a 2 MW PMSG-based WTG are built. The simulation and experimental results show that the synchronization frequency can accurately map the grid frequency changes in real time under the premise that the DC-link voltage keeps constant after using the proposed control method, and the influence of the disturbance terms on the synchronization frequency does not exceed 0.5%.

关 键 词：风电机组 直流电容动态 自主同步 电压源控制 统一控制结构 硬件在环实验平台 

分 类 号：TM315[电气工程—电机] TP273[自动化与计算机技术—检测技术与自动化装置]