永磁风力发电机绕组过电压致损规律及保护对策研究

The accidents of Permanent magnet synchronous generator (PMSG) winding breakdown and burn up happened frequently, in addition to the winding manufacture process reason, it has been founded the influence of inverter PWM operation produced high frequency over-voltage pulse by long cable is more serious to the damage of generator winding, the damage mechanism and the influence rule isn’t clear by recent study. Applicants combine with academic world research hot spot and wind farm practical, carry out the following research: The over-voltage pulse wave superposition process principle that produced by generator side converter PWM high frequency pulse wave reflected through long cable transmission and over-voltage pulse wave distribution; The theory of suppress the high frequency pulse wave filter installation position, the design of the structure and component parameter optimization; The over-voltage pulse character after filtered and its uneven distribution in the winding rule and influence factors of determining winding insulation by the harm of the most dangerous area; Based on the above study and put forward measures of dealing with generator over-voltage. Adopts theoretical analysis modeling, software simulation and lab experiment combine site experiment, from the fault source to reveal PMSG winding loss mechanism and over-voltage uneven distribution by the long cable generated, study the over-voltage suppression measures and improve the effectiveness of existing wind power generator protection, the research conclusion can be broaden to the application principle of similar doubly-fed wind power generator rotor and photovoltaic inverter over-voltage protection work.

永磁风力发电机绕组击穿和烧毁事故频发，除绕组制造工艺原因外，近期研究发现变流器机侧的PWM高频脉冲经长缆传输产生的过电压，对绕组的危害也较严重，其致损规律和影响因素尚不明确。申请者结合学术界研究热点和风电场运行实际，为此开展以下研究：发电机侧变流器PWM高频脉冲波经长电缆传输反射和叠加产生过电压的原理过程及过电压分布规律；抑制高频脉冲波滤波器的位置、结构和元件参数的原理及优化；滤波后的过电压脉冲波特征及过电压在绕组内不均匀分布规律和影响因素，确定绕组绝缘受危害的最危险区域；基于以上研究提出应对发电机过电压的对策。采用理论分析建模、软件仿真、实验室实验和现场实验相结合的方法，从故障源头揭示永磁风力发电机绕组经长电缆产生过电压致损机理和过电压不均匀分布规律，研究过电压抑制对策，提升现有永磁风力发电机保护的有效性，研究成果还可拓展应用到原理类似的双馈风力发电机转子和光伏发电逆变器的过电压保护中。

永磁风力发电机绕组击穿和烧毁事故频发，除绕组制造工艺原因外，近期研究发现变流器机侧的PWM高频脉冲经长缆传输产生的过电压，对绕组的危害也较严重，其致损规律和影响因素尚不明确。申请者结合学术界研究热点和风电场运行实际，为此开展以下研究：发电机侧变流器PWM高频脉冲波经长电缆传输反射和叠加产生过电压的原理过程及过电压分布规律；抑制高频脉冲波滤波器的位置、结构和元件参数的原理及优化；滤波后的过电压脉冲波特征及过电压在绕组内不均匀分布规律和影响因素，确定绕组绝缘受危害的最危险区域；基于以上研究提出应对发电机过电压的对策。采用理论分析建模、软件仿真、实验室实验和现场实验相结合的方法，从故障源头揭示永磁风力发电机绕组经长电缆产生过电压致损机理和过电压不均匀分布规律，研究过电压抑制对策，提升现有永磁风力发电机保护的有效性，研究成果还可拓展应用到原理类似的双馈风力发电机转子和光伏发电逆变器的过电压保护中。