具有限流功能的新型统一潮流控制器及其控制

A New Unified Power Flow Controller With Fault Current Limiting and Its Control

统一潮流控制器(UPFC)对提高电网输送容量、控制线路潮流有明显的优势,但在电力系统发生短路故障下的UPFC自身安全问题十分关键。此处提出了一种具有限流功能的新型UPFC拓扑并给出了相应的控制策略,所提出的新型UPFC拓扑具有短路限流功能,在系统故障时具有很强的自我保护能力。正常情况下,所提出的新型UPFC运行在传统UPFC模式并根据控制指令调节系统潮流;当发生系统短路故障时,可运行在故障限流模式保障设备安全。最后通过硬件在环实验验证了所提新型UPFC拓扑及其控制策略在系统发生短路故障时,对故障电流控制的有效性和正确性。

The unified power flow controller(UPFC) has obvious advantages in improving the transmission capacity of the power grid and controlling the power flow.However,the security of the UPFC is critical when the power system is short circuit fault.A new unified power flow controller topology with current-limiting function is proposed and the corresponding control strategy is given.The proposed new UPFC topology has short-circuit current-limiting function and strong self-protection capability in case of system failure.Under normal circumstances,the proposed new unified power flow controller runs in the traditional UPFC mode and adjusts the system power flow according to the control instructions.When a system short-circuit fault occurs,it can be run in fault current limiting mode to ensure device safety.Finally,the effectiveness and correctness of the proposed UPFC topology and its control strategy for fault current control in the case of short-circuit fault occurred in the system are verified by the in-loop experiment platform.