Designing And Optimizing Parabolic Trough Solar Energy System Based On ORC Cycle

Trough solar power generation is currently the most mature technology of solar thermal power generation.Although solar thermal power generation is more affected by weather,it can increase the number of hours of operation by setting up a heat storage system.The intensity density of solar radiation is small,and the heat energy obtained by trough concentrating is usually in the middle and low temperature range,and the organic Rankine cycle is one of the ideal solutions for the high efficiency utilization of the middle and low temperature heat sources.In this paper,a trough type solar thermal power generation system based on organic Rankine cycle is established,and its optimal design and operation optimization are as follows:The SAM software is used to design the solar energy mirror field.The concentrating heat collector in the loop is regarded as a calculation node.The temperature,mass flow and energy change of each node are analyzed,and the heat field calculation model is established.A double tank system is selected as the research object,and each heat storage tank is analyzed and calculated.Based on the geometric size and heat transfer parameters of heat storage medium,a mathematical model of heat storage system is established,and the calculation model of heat exchanger is established.Finally,a complete mathematical model of solar collector and storage module is obtained.The performance calculation model of the organic Rankine cycle power generation system brought back to heat was established by MATLAB,and the cycle efficiency,power generation power and related system parameters were calculated.On this basis,the solar collector field model is combined with the organic Rankine cycle performance calculation model,and the simulation analysis system of the trough type power station is designed.By using the established simulation analysis system,the solar power and the capacity factor of the power plant are optimized as the target of the annual output of the power station,the electric cost and the capacity factor of the leveling degree.The calculation results show that when the solar multiple is 2.5 and the storage time is 6h,the performance of the power station is optimal.Through sensitivity analysis,the parameters such as the distance between the collector,the height of the tank and the heat loss coefficient of the regenerator are optimized.In view of the optimized power station,according to the annual solar radiation intensity distribution in Wuhan area,the operation mode of the power station has been optimized.The operation scheme of three kinds of power stations is proposed.According to the operation mode of different schemes,the dispatching score of the power station is combined and collocated.By calculating the performance parameters of the power station and the operation situation of the power station under the influence of different typical days,the maximum annual output power and the lowest operating mode are obtained.The research of this paper provides a reference for the design and operation of solar energy organic Rankine cycle power generation system with heat storage.