Future generation will mostly depend on renewable energy resources due to lack of conventional energy resources, so existing renewable energy resources are being modified for efficiency improvement and enhancement of power generation. Water is a huge resource of renewable energy used in hydro-electric power plants. The purpose of this paper is to control the output voltage and frequency of permanent magnate synchronous generator installed in a hydro-electric power plant as a main generator. Variation in flow of water disturbs the speed of hydraulic turbine which results in variable voltage and frequency at the generator output. Therefore in order to obtain the constant voltage and frequency at the load side controlling is much important, hence to reduce the change in system voltage and frequency to the smallest possible value, a voltage frequency controller is required. In this research, the controller is following an artificial intelligence technique, i.e. Ant Colony Optimization and the controller is providing the better results as compared to other controlling techniques. Mathematical modelling of hydro-electric power plant in matlab is shown in this paper and also a complete simulation model is designed in simulink. As a conclusion the output voltage and frequency variations at PMSG of hydro-electric power plant are reduced.

Key words: hydro-electric power plant, permanent magnate synchronous generator, mathematical modeling, ant colony optimization, controller