The Research Of Hydro And Thermal Optimal Generating-capacity Structure Considering Technical Characteristics Under Capacity Mechanisms

It’s necessary for the power system capacity planning to ensure generation capacity adequacy and generation investment economy. In the traditional power industry, it’s clear that the power administrative department has the responsibility to establish generation capacity planning. However, with the power system deregulation, it has been unclear that who has the responsibility for generation capacity planning under decentralized decision-making, and how to design an effective capacity planning mechanism has attracted extensive attention worldwide among researchers, government departments, power system organizations of design, operation, regulatory and management. It has been suggested by many studies at home and abroad that the capacity mechanism should be established to ensure the generation capacity planning. Through the capacity compensation fund for investment cost recovery, the capacity mechanism can motivate new generation capacity investment to ensure sufficient generating capacity. Several capacity mechanisms have been set up by regional power systems at home and abroad to guide generation capacity investment for generation capacity adequacy. The optimal generating-capacity structure has been taken as a criterion for the generation investment economy of capacity planning. The optimal cost of generation capacity investment and generation operating could be obtained under the optimal generating-capacity structure. However, the economic characteristics of the generation unit have only been considered for the optimal generating-capacity structure but neglected of the technical characteristics. The capacity planning result obtained under the optimal generating-capacity structure will not be able to fully reflect the physical characteristics of the unit and its contribution to the power system. The technical characteristics of the unit will be considered to the analysis of the optimal generating-capacity structure in this paper. And it has also been analyzed that if the capacity mechanism would be able to guide the generation capacity achieved optimal generating-capacity structure. The main research work and the results are as follows:Firstly, with the same as economic characteristics the generation unit, the maximum electric quantity limit of hydropower unit has been integrated into the optimal generating-capacity structure, so do the ramp rate and the minimum output of thermal power unit. By establishing the optimal generating-capacity structure model, the hydropower generation capacity with the maximum electric quantity limit has been determined. By transforming the ramp rate and the minimum output of thermal power unit into the economic characteristics of the thermal unit, the optimal generating-capacity structure has been completed by considering the technical characteristics of the unit.Second, it has been analyzed that how the capacity mechanisms to effect the optimal generating-capacity structure. Based on the analysis of the profit of generation unit under several capacity mechanisms, such as capacity payment, capacity market, long-term strategic reserve contracting, two-part price mechanism and energy-only market, the generating-capacity structure will be obtained with the optimal long term costs under the capacity mechanisms above.Finally, by the capacity investment model base on system dynamics, it has been analyzed that if the capacity mechanisms will be able to guide the generation capacity achieved optimal generating-capacity structure. By the economic incentive to guide capacity investment from the financial compensation of capacity mechanisms, generation capacity will be determined in accordance with the profit. Following this dynamics, the capacity investment dynamics model has been established for capacity mechanisms above. Based on this model, the static and dynamic characteristics of the capacity investment have also been analyzed for capacity mechanisms.