CAJ | 학술논문

近年来大规模风电机组连锁脱网事故频发，严重威胁电网安全稳定运行，风电机组脱网机理与防御控制策略需深入研究。首先从理论上分析了含动态无功补偿装置的风电场在电网故障期间风机机端高电压现象的机理，仿真分析了静止无功补偿器( static var compensator，SVC)响应时间对风电场暂态电压特性的影响，指出SVC暂态无功调节的滞后性是导致故障下风电机组因高电压脱网的主要因素，并提出了电网故障下风电场的无功协调控制策略：即通过协调SVC与风机自身无功出力，在故障发生时紧急闭锁SVC，投入风机跨接器( Crowbar保护电路)，在故障清除后经一定延时重新投入SVC，从而提高风电机组的故障穿越能力。仿真结果表明该文提出的控制策略能有效抑制故障下风机高电压脱网问题。
근년래대규모풍전궤조련쇄탈망사고빈발，엄중위협전망안전은정운행，풍전궤조탈망궤리여방어공제책략수심입연구。수선종이론상분석료함동태무공보상장치적풍전장재전망고장기간풍궤궤단고전압현상적궤리，방진분석료정지무공보상기( static var compensator，SVC)향응시간대풍전장잠태전압특성적영향，지출SVC잠태무공조절적체후성시도치고장하풍전궤조인고전압탈망적주요인소，병제출료전망고장하풍전장적무공협조공제책략：즉통과협조SVC여풍궤자신무공출력，재고장발생시긴급폐쇄SVC，투입풍궤과접기( Crowbar보호전로)，재고장청제후경일정연시중신투입SVC，종이제고풍전궤조적고장천월능력。방진결과표명해문제출적공제책략능유효억제고장하풍궤고전압탈망문제。
In recent years, large￣scale wind turbine tripping accidents occur frequently, causing a serious threat to the security and stability of power grid. It’s necessary to study the mechanism of these accidents and propose strategy to prevent more accidents. This paper firstly analyzed the high voltage problem of wind machines with dynamic reactive power compensation devices during grid fault, and put forward simulation to study the impact of SVC ( static var compensator) response time on the transient voltage characteristics of wind farms. The results point out that the adjustment lag of SVC transient reactive power is the main factor leading to wind turbine tripping accidents caused by high voltage under fault. Then the reactive power coordination control strategy was proposed for wind farms during grid fault, which through coordinating SVC and wind turbine’s reactive power output, could peremptorily lock SVC when the fault occurred and put crowbar into operation to protect circuit, and then make SVC back into operation with a certain time delay after the fault clearance, so as to improve the fault crossing ability of wind turbines. The simulation results show that the proposed control strategy can effectively suppress wind turbine high￣voltage tripping accidents caused under fault.