A Study of Economic Load Dispatch of Thermal Generation with Integration of PV in The State of Telangana, India
Abstract - In this paper, economic load dispatch of thermal power integrated with solar photo voltaic generation in the state of Telangana, India is discussed. The load demand of the state is increasing rapidly and the peak demand has crossed 13,500 MW. As there is a crisis for conventional sources like coal for TPP which is the major source of power generation in all countries, they have to be integrated with other nonconventional sources inorder to minimize their utility and to reduce pollution. India has great potential for solar power because of its high solar irradiance index at various places and also their operational costs are less. For TPPs the cost of operation is more and also each generating unit usually has a unique cost-per-hour characteristic for its output operating range. To meet for the load requirements and for reliable, sustainable power supply and for most economic operation, solar power plants are to be installed evenly across various geographical locations in addition to the already existing ones and integrating them with the grid is necessary. In this paper, the allocation of the load demand to the various generating units, both SPP and TPP i.e the Load Dispatch considering the various limits and constraints of the units of standard IEEE-30 bus and IEEE-118 bus test systems for different load demands integrated with evenly installed SPPs in the state of Telangana to obtain the most economical operating costs are discussed.
ELD is solved by considering the fuel cost coefficients, valve point loading effects, penalty due to emissions, transmission losses minimum and maximum capacities, ramp rate limits and prohibited operating zones of thermal power units and the minimum, maximum and average capacities based on the solar irradiance values taken for the peak solar hours in an year and a factor of overestimation, underestimation of available solar power for PV units. The transmission losses are not considered for PV as the units are placed in distribution network. The optimization is carried out using Non-linear Generalized reduced gradient (GRG) algorithm in solver without and with integration of PV with TP and the results are compared.
It is found that with the integration of PV units at evenly distributed locations, the transmission line losses and cost of load dispatch is greatly decreased more so in case of IEEE-118 bus system compared to IEEE-30 bus system.
Keywords - Load Demand, Cost of Dispatch, Photo-voltaic, GRG Algorithm.