Design principles of a transformer substation using a thyristor-controlled reactor

The study aims to ensure the maintenance of nominal voltage levels in power supply systems with high efficiency under conditions of input voltage instability or load current fluctuations. The research focuses on a transformer substation that incorporates a proposed thyristor-controlled reactor. The MATLAB software was employed to develop a simulation model of the analysed transformer substation, to investigate its performance, and to evaluate continuous voltage regulation. Advanced design principles, control algorithms, and operational methods for the transformer substation were developed based on the proposed thyristor-controlled reactor. The study demonstrates that the device should be connected in series on the high-voltage side of the substation, between the circuit breaker and the primary winding of the power transformer. Numerical experiments confirm the feasibility of implementing the proposed device, along with its control algorithms and operational methods, in transformer substations where power supply systems encounter difficulties in maintaining stable voltage levels with high efficiency. The external, regulating and stabilising characteristics illustrate the performance of existing power supply systems prior to and following modernisation, particularly under overdeviations and overvoltages resulting from external or internal electrical parameter variations. The proposed device can be used in transformer substations for power supply systems with voltages of 35/(10–6) kV and (10–6)/0.4 kV, characterised by overdeviations, fluctuations and overvoltages. Consequently, the optimal application domain for the device is power supply systems requiring multistage, narrow-range voltage regulation with high efficiency.