The Process of Primary Frequency Control of the Power Systems Investigation Using Modeling Methods

General primary frequency regulation (GPFR) is employed within the power system to limit frequency variation deviations from a reference value in positive and negative directions, ensuring safe power object operations and reducing the prevalence of power outages. Requirements for primary frequency regulation are presented in normative documents. They regulate the statism of regulation (from 4 to 6%) and the minimum time of increase/decrease of power plant capacity. However, in practice, undamped frequency fluctuations and unnecessary consumer and generation outages occur in frequency regulation in power systems in some emergency disturbances. In 2020, the Norilsk-Taimyr power system experienced an accident with an unbalanced active power of 40 MW. The frequency was regulated by two power plants - Ust-Khantai and Kurey HPPs. Low-frequency oscillations occurred for 27 seconds. Only with a statism of 25 percent, which does not match the standards, a stable frequency control could be achieved. This case highlights the problem of suboptimal GPFC laws in frequency control of multiple power plants. This paper presents the modelling of the power system in MATLAB environment to investigate the transients in GPFC. Based on the data obtained, the shortcomings of the control laws used can be noted and criteria for the creation of modernized control algorithms can be put forward.