| The fossil energy depletion and the deterioration of environmental issues have vigorously promoted the development of renewable energy on a global scale. Wind power has been widely used as a relatively mature technology among renewable energy. However, due to the defect of wind resource's uncertainty, wind power exhibits the fluctuation in different degrees. With the increase of wind power scale yearly, the problem and challenge of wind power integrated to the grid has been upgrading, including the impact on power quality and peak shaving pressure on the regular crew because of the wind power output fluctuation, gird scheduling problems caused by the low forecast accuracy, etc. The emergence and development of energy storage technologies provides an effective way to solve the problem of wind power integrated to the grid. An appropriate type and size of energy storage power supply can be configured for the wind farm to form the combined power generation system with wind power and energy storage. With its fast power handling action and electrical energy time shift capability, energy storage can amerliorate the characteristics of wind power output, make it a relatively controllable and adjustable power supply and improve the stability of its operation integrated to the grid. Through the subdivision of combined application scenarios with wind power and energy storage, this paper proposes a needs assessment methodology for energy storage, which includes “type selection-capacity configuration-preference assessment” elements, which provides the planning guidance for policymakers and has a practical value.At first, this paper refined the technical and economic characteristics indicators of various types of energy storage to form its comprehensive index system. An integrated static model was established to characterize its charge and discharge process, using batteries as the main target. According to the difference of the control target and time scale, three application scenarios were proposed, including “stabilizing fluctuations”, “tracking program output” and “peak shaving and valley filling”. The indexes of corresponding scenarios were refined as well. Based on the comparison of various types of energy storage and the comprehensive index system, the appropriate types of energy storage for the three scenarios were determined by using the analytic hierarchy process.Based on the life cycle cost theory and the equivalent effect in operation process, this paper established the cost-benefit economic model of energy storage by using the net present value method. Combining the equivalent cycle life method and the rainflow counting algorithm, a method for calculating the operation life of energy storage was proposed with batteries as the main target. According to the result of choosing energy storage type, this paper put forward the appropriate capacity configuration strategy for the three scenarios and formed several feasible configuration schemes by simulating with the data from Zhangbei wind farm and so on. In the “stabilizing fluctuations” scenario, the moving average filter method and the wavelet packet decomposition method were used. In the “tracking program output” scenario, this paper used the particle swarm optimization to optimize the energy storage cost-benefit economic model. In the “peak shaving and valley filling” scenario, the divison of the inner-outer control area and the first-order low-pass filter principle was used.Finally, in order to assess the advantages and disadvantages of these configuration schemes in the technical and economic comprehensive performance, this paper used the preference ranking organization method for enrichment evaluations and the analytic hierarchy process to sort them and picked the best scheme under each scenarios. At the same time, the geometrical analysis for interactive assistance was used to do the sensitivity analysis for the influence on the sorting assessment result depending on the evaluation indexes of each scheme. |
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