Scenery (CHAI) Co-generation System Storage Capacity Configuration Method

The new energy generation, such as wind or solar power generation, has been developed in a high speed, and the economy and output power stability of wind/solar power system is attracting more attention. Although the PV-wind-diesel-storage hybrid system can ensure a better stability because of the resources’complementary characteristic, some problems such as the ineffective utilization of resources, high cost but low operation profit of hybrid system, are ubiquity in the field of hybrid system at present. This situation seriously affects the development of PV-wind-diesel-storage hybrid generation industry. Over the long run, an optimal placement of hybrid system must be done to optimize the economic index and reduce the control difficulty on the premise of stability assurance.To realize the optimization of economic index based on the stability of system, a kind of single objective optimization method was used during the research process of capacity configuration. The main content of this paper was listed as follows.1. The operation characteristics of wind turbine generator, PV module, diesel generator and energy storage battery have been studied respectively in depth to lay a foundation of further study on capacity configuration. Operation reliability indexes and constraints were designed according to the analysis on the operation reliability of major generating equipments. These constraints ensure a reasonable equipment selection to improve the utilization of resources and reduce the difficulty of control.2. The structures and characteristics of the grid-connected, grid-independent and micro-grid PV-wind-diesel-storage hybrid system have been analyzed in depth. The system reliability indexes and resource utilization indexes have been designed as constraints respectively. Especially, according to the extreme case of micro-grid system splitting, the battery capacity demand was proposed and has been designed as constraints.3. According to the problem of high system cost but low operation profit, the cost composition and profit composition of system have been analyzed, and the cost minimization and annual net profit maximization functions have been designed respectively to realize the optimization of system economic index. The net profit function would be more accurate after considering the emissions trading income.Based on research work above, the capacity configuration models of the grid-connected, grid-independent and micro-grid PV-wind-diesel-storage hybrid system have been designed respectively, and have been solved according to genetic algorithm. The calculation example and verification result showed that devices selection is reasonable and the system makes full use of the complementary characteristic of wind-solar resources. The cost minimization or annual net profit maximization has been achieved on the premise of output stability in grid-connected system, load following in grid-independent system and splitting stability in micro-grid system respectively.