Transformer Substations are designed to receive, convert, and distribute electric energy of three-phase alternating current of 50 Hz frequency and to implement low-voltage switchgears and control devices of AC engines with main bus current up to 2500 A. They are used for power supply of auxiliary loads of nuclear, thermal, and hydroelectric power plants and other facilities with auxiliary power transformers 250 kVA - 1600 kVA, voltage 6/0.4 kV or 10/0.4 kV.

Transformer Substations perform the following functions: 

• provide power to consumers;
• control actuators;
• protect against:
• current overloads,
• single-phase and interfacial short circuits in the network,
• short-circuits to ground;
• generate a ringing alarm in case of malfunction or power supply parameter deviations; 
• monitor power supply parameters;
• measure and display:
• values of line/phase to ground voltages,
• current of each in-feed phase,
• frequency,
• power (actual and reactive);
• common nonlinear distortions.

Transformer substations are also intended for other industrial facilities, such as:

• systems of urban electrical networks;
• power supply;
• oil and gas industry facilities;
• agriculture;
• mining industry;
• railway industry, etc.

From 2015 to 2020, more than 20 transformer substations were put into commercial operation: 

• Zaporizhzhia nuclear power plant in 2015;
• South-Ukraine nuclear power plant in 2019, 2020.