基于功率平面隐极发电机低励限制与失磁保护配合研究

同步发电机组的低励限制需先于失磁保护动作,而低励限制和失磁保护的判据完全不同,因此二者的整定与配合一直是网源协调的一个难点.从隐极同步发电机静稳边界的功率方程出发,推导出静稳边界在功率平面上消除了机端电压的抛物线型表达式.将失磁保护与低励限制的判据统一为功率平面的抛物线型静稳边界,提出了一种低励限制与失磁保护配合的新方...

Coordination of the low excitation limit and loss of excitation protection of a round-pole generator based on a power plane

The low excitation limit of a synchronous generator set needs to operate before the loss of excitation protection. However, the criteria for the low excitation limit and the loss of excitation protection are completely different. Therefore their setting and coordination have always been a difficulty in network source coordination. Using the power equation of the static stability boundary of a round pole synchronous generator, the parabolic expression of the static stability boundary eliminating the terminal voltage on the power plane is derived. The criteria of loss of excitation protection and low excitation limitation are unified into the parabolic static stability boundary of the power plane, and a new scheme combining these criteria is proposed. The scheme has clear physical meaning and is easy to set. This can ensure the strict cooperation between loss of excitation protection and low excitation limit. The effectiveness of the new scheme is verified by the analysis of and calculation for a 600 MW thermal power generation unit. It ensures the safe and stable operation of the unit and the power grid while improving the leading phase operation capacity of the synchronous generator unit. This work is supported by the Science and Technology Project of the Headquarters of State Grid Corporation of China (No. 5700-202055332A-0-0-00).