Coordination of Power Overload Emergency Automatics with the Stability Control Systemof Unified Power System of Russia

Power overload automatics prevents a loss of power system transient stability due to unpredictable severe active power growth in a group of power lines called a controlled section of the power system. Devices of such automatics compare transmitted active power with a constant value, which is set according to calculations at the design stage. At the same time, the stability control system in a near real-time mode calculates a greatest possible value of controlled section transmitted power, which is changed during the time as it depends on a variety of parameters such as: operational state of commutation devices, generated and consumed power, level of voltages. The maximum transmitted power value chosen does not take into account the power overload automatics settings, which can lead to excessive operation of such automatics in a case where possible transient stability cannot be lost. The paper proposes a solution for the problem.