转子角动量分析及其在一次调频中的应用

Analysis of the rotor angular momentum and its application in primary frequency regulation

在孤立电网中快速、准确地选出临界机群,加强临界机群的调频能力,能够提高孤网的稳定性。从发电机原始转子运动方程出发,研究了不平衡功率积分和转子角动量对时间积分的物理意义;分析了它们同惯性时间常数的关系,提出了根据发电机角动量增量选择临界机群的性能指标。将角动量选择临界机群与暂态稳定计算中的分段计算法选择临界机群相比较,体现了角动量选择临界机群的优越性。通过优化调速器参数加强临界机群的一次调频能力,从而提高孤立电力系统频率稳定性。并以孤网四机系统为例,用仿真实验验证了方法的可行性和优越性。

Choosing the critical generators quickly and accurately and strengthening the frequency regulation ability can improve the system stability of isolated grid. Based on the generator rotor motion equation, this paper studies the physical significance of rotor imbalance of power and angular momentum points to time integral. Their relationship with the time constant of inertia is analyzed and the performance index of choosing critical units according to incremental angular momentum of the generator is proposed. Compared with the angular momentum index and transient stability calculation of subsection calculation method, its superiority is reflected. By optimizing the governor parameters of critical units, the regulation ability of a critical frequency is strengthened, thus the system frequency stability is improved. Taking the four-machine system in the isolated grid as an example, simulation results verify the feasibility and superiority of the method.