Keywords: automatic generation control, AGC, availability–based tariff, ABT, load frequency regulation, frequency linked tariff, India, electricity markets, price signals, IEEE 14 bus
Automatic generation control scheme for frequency linked price signal followed in India
Indian electricity market has adopted a concept of frequency linked commercial tariff system, commonly referred to as availability–based tariff (ABT), where variation in system frequency is used as market signal to encourage utilities to change generation in real time operation. As frequency varies with real power imbalance, proper incentive is rewarded for automatic generation control (AGC) service provided by the generating utility for making up the real power mismatch. In ABT, the rate of unscheduled interchange (RUI) for AGC service is fixed depending upon the frequency condition prevailing at that time. The conventional AGC system though tries to bring the frequency error to zero but it would be an ineffective solution for participating generating utilities under ABT since incentive/penalty varies with frequency. This paper investigates the rules and advocacy of ABT more strategically and develops a model for AGC based on conventional if–then logics for load–frequency regulation scheme that will respond to the frequency–based price signal in a profitable manner. The proposed model is tested on IEEE 14 bus system and part of northern region grid of India.