Collaborative Control of Hydroelectric and Thermal Plants Units During Emergency Departures of Frequency

Abstract

The transients in the electric power system in the event of a sudden imbalance in active power are considered. This fact makes it possible to calculate the process of changing the frequency taking to account the dynamic properties of hydroelectric and thermal power plants units. Mathematical model of the power system which can calculate the process of changing frequency and take dynamical properties of hydro-and turbo-generators is considered. The model of power station with an equivalent generator and simplified thermal generating unit is also presented. Verification of the model conducted by calculating to experimental comparison of frequency in the energy system and active power of energy units with experimental check-up is completed successfully. The isolated power system of the Taimyr Peninsula, which contains two hydroelectric power plants and three thermal power plants, was taken as the basis for verifying the model. The stations are located relatively close to each other (maximum distance of about 300 km), and are connected by 220 kV lines. The use of the proposed control method in power systems with weak links has not been studied. In this paper shown that the use of simplified dynamic characteristics model has not been lead to solve the significant deficiency innaccuracy while solving this issue. In the first moment after active power imbalance a calculation made of transient phenomena and taken into account acceleration exposure of regulation systems of hydro and turbogenerators is presented. The frequency deviations can be decreased till 8 % by a system development of hydrogenerators. The combined control of hydro and turbogenerators is necessary for effective limiting frequency deviation of turbo- and hydro- generators is necessary for effective limiting frequency deviation. In this case the frequency deviations can be decreased to approximately 2 times.