On The Operation And Control Of Pumped Storage Power Plants In Power Systems With Large-Scale Wind Power Generation

The active power regulation problems in power systems integrated with large-scale wind power generation,such as peak-load regulation and frequency regulation,have become the main factors which restrict further development of wind power.As one of the most mature technology for large-scale energy storage,pumped storage power plants(PSPs)will play an important role in wind power integration for its flexible ability in peak-load and frequency regulation.However,the operation and control strategies of most current PSPs are inherited from that in traditional power systems,and have not been adjusted for the situation of wind power integration.This limitation has enormously restricted the regulation qualities of PSPs in wind power systems.In order to improve the regulation qualities of PSPs,this dissertation built a multiple operation and control framework for PSPs based on the stepwise refinement of temporal and spatial scales.This operation and control framework has improved the regulation ability of PSPs and relieved the active power balance problems in wind power systems,which has positive effects on the integration of large-scale wind power and the frequency control of power systems.The dissertation firstly analyzed and modeled the wind power characteristic from the perspective of space-time series.Measured data of wind power were analyzed on different time scale,especially for the coupled spatial-temporal correlation.Then,Space-Time Auto Regressive Moving Average(STARMA)model was used to describe the spatial and temporal correlation of multidimensional wind power series.Simulation results showed that STARMA model has restored not only temporal autocorrelation,but also time shifting characteristics of spatial correlation of the original wind power series,which essentially reflects the spatial and temporal characteristic of real wind power series.This model can be used to produce huge amount of simulated data,which have same characteristics with real wind power data,and can provide basics for the planning and operation of wind power integration.To solve the wind curtailment problem,the dissertation carried out detailed research on the peak-load regulation of PSP from the perspective of power system.Mechanism of the wind curtailment,which was concluded to be caused by the reverse-peak characteristic of wind power output,was firstly analyzed.Then,optimazation model for PSP peak-load regulation was built by formulating a mixed integer linear programming problem with optimization objective of minimizing wind curtailment,in which operational characteristics of power system and PSPs were also taken into consideration.Influence factor of wind curtailment,such as power output limitation of thermal units and transmission capacity,were validated,and peak-load regulation of PSPs were optimized to mitigate the wind curtailment.Finally,the optimal capacity of pumped storage to make the whole wind curtailment minimal was also calculated.For the primary frequency regulation of wind power system,a robust control strategy for PSPs was proposed for PSPs.A state space model of the entire power system was derived and characteristics of short-time wind power variations and dynamics of PSPs were implemented into this model.Then,the H?-based robust controller for PSP was synthesized by using the linear matrix inequality method.A test system was finally used to verify the performance of the proposed control strategy and time domain simulation results indicated that this robust control design significantly reduces the system frequency deviations and enable the pumped storage generators more responsive to wind power variations.In addition,with PSPs taking more responsibility for frequency regulation,thermal generators will be less affected from the influence of wind power fluctuation.Besides,this dissertation also proposed to utilize the power regulation capabilities of ternary pumped storage units(T-PSP)and adjustable speed pumped storage units(AS-PSP)in their pumping mode in order to extend the range of wind power regulation.Based on the analysis of operation characteristic of T-PSP and AS-PSP,dynamic model and control strategies of both units were built.Then the wind power regulation process was simulated,and results showed that system frequency deviations have been significantly reduced,which indicates that the proposed strategy of utilizing the pumping power regulation capabilities to address wind power variation is technically feasible.With the development of large-scale wind power bases in China,wind power integration and system frequency control problems have become more and more prominent.Hence,conclusions obtained in this dissertation on the peak-load regulation and frequency regulation of PSPs,will be valuable and practical for the integration of large-scale wind power.