Dynamic Interval Economic Dispatch Considering Unit Reserve Responsiveness

Power system economic dispatch has been widely concerned from the1930s. The development process of economic dispatch has gone through four stages, static economic dispatch, dynamic economic dispatch, uncertain economic dispatch and renewable energy generation economic dispatch. Nowadays, large-scale renewable energy integrated power system, it will bring greater challenges to dispatch of thermal generators. If unit commitment has already given, for mayor contradictions of dynamic economic dispatch considering renewable energy accommodation, it has become a hot research question to improve the response speed of spinning reserve.Firstly, This paper proposed dynamic interval economic dispatch of power system considering unit reserve responsiveness based on previous studies of the static interval economic dispatch. Then, the background, mechanism and significance of the model is analyzed in detail. The static interval economic dispatch is only for a certain time section of the daily load curve, without considering the coupling between the time sections. Therefore, with respect to the static interval economic dispatch, the study of dynamic interval economic dispatch has practical significance.Dynamic economic dispatch is a high-dimensional, non-linear optimization problem, solving methods can be divided into global optimization method and decoupling optimization one period by one period. This paper proposed a practical method for solving the dynamic interval economic dispatch based on the second method-forward and backward method. Through forward direction, the algorithm can determine the initial dispatching base point, and insufficient spinning reserve considering the future load, wind power forecasting. With respect to the insufficient spinning reserve, the initial dispatch base point is corrected through backward direction, following the principles that the down-regulation units should change to two-direction-regulation ones and the up-regulation units to two-direction-regulation ones.Then, the reserve responsiveness in the limited direction will be improved, it just be able to fill up the insufficient spinning reserve during forward direction, at the same time, economy and interval satisfaction degree both can be satisfied. The algorithm take forward direction as the main function and backward direction the auxiliary function, that is, if the spinning reserve can not be satisfied during forward direction, the initial dispatching base point will be corrected through backward direction immediately.Then it will continue to push forward until all the constraints are satisfied.The algorithm primely solves dynamic interval economic dispatch, the calculation is relatively simple.Finally, its correctness is verified by calculation on ten unit system.