基于涉网保护的低励限制、失磁保护与失步保护配合的研究

网源协调中发电机组涉网保护问题对电网运行和发电厂涉网设备运行的影响日益显著。对实际电厂中低励限制、进相能力和失磁保护整定不合理的问题进行了明确的阐述,提出了它们之间的整定配合原则。在电力系统继电保护中,失磁保护是最重要、最复杂的保护之一,失磁保护与失步保护都是采用测量阻抗的变化规律作为动作的判据,在阻抗平面上存在重叠动作区域,因此两者在配合上存在冲突。由于功角能够实时测量,在线整定,具有自适应的特性,提出了基于功率角闭锁的方法来解决发生失步时失磁保护可能抢先误动的问题。通过仿真验证了上述结论的正确性。

Research on coordination of low excitation limit, loss of excitation protection and out-of-step protection based on grid-related protection

In the coordination of power source and grid, the issues of grid-related protection of generator will exert an increasing significant on running of power grid and network equipment. For the unreasonable setting problems of low excitation limit, phase advance capacity and loss excitation, coordination principles among them are provided. In power system protection, the loss of excitation protection is one of the most important and complex protections. Loss of excitation protection and out-of-step protection both use the variation of the measured impedance as the operation criterion of the operation, and there is an overlap operation area in the impedance plane, so loss of excitation protection and out-of-step protection exist confliction in coordination. For the measurement of power angle is real-time, on-line, and automatic adaptive, a method of solving loss excitation protection and out-of-step protection is provided based on the power angle locking. Simulation verifies the correctness of the conclusion.