Optimum dispatch of turbines in a low head hydropower plant for a given total flow rate and available variable head - a case study for Moragahakanda power station in Sri Lanka

Abstract

Reservoir-based hydropower stations primarily operate based on utility demand, while others cater to irrigation and domestic water requirements. As a result, hydropower generation is not consistently at full capacity, and turbines often operate at partial loads. Optimizing hydropower generation and scheduling can lead to significant profits for both the power company and the country. Optimization of hydropower generation is a nonlinear problem. The nonlinearity occurs due to the generating characteristic of the machines, whose outputs are generally a nonlinear function of water discharge and net hydraulic head. This paper presents a strategy for the optimum distribution of dispatched power among its available generating units by taking into account both the nonlinear characteristic and the head loss effect. The objective is the maximization of the total power generation for a low-head hydropower plant under varying head and for a given total water discharge rate. This development is done based on the Moragahakanda hydropower station and, MATLAB software has been utilized to construct mathematical models and solve the optimization problem. The implementation of the proposed optimization model resulted in a significant increase in power generation at the Moragahakanda hydropower station, highlighting the effectiveness of the model in improving hydropower generation.