Research On Trading Mechanisms Of Wind/Solar/Storage Power Station In Power Market

By means of energy storage technology storing and releasing energy in real time, the output power of wind/solar/storage power station (WSSPS) can achieve predictability, controllability and schedulability. However, on the one hand, our country faces serious wind curtailment issue at present, WSSPS also always been in a state of abandoning wind power, so that regulating ability of its energy storage system can’t function adequately which leads to a waste of system resources; on the other hand, the transfer passage of wind power may be underutilized in wind curtailment situation, because the insufficient output of wind farm caused by their own reasons. Therefore, it is very necessary to establish effective market mechanisms to urge WSSPS participate in power market, to achieve mutual benefit and win-win of transactions and efficient use of resources.In order to know the characteristics of WSSPS, this paper analyzed the three systems from the structural point, analyzed the seven kinds of operating modes and four kinds of control strategies of WSSPS from function point. And based on the actual operation condition of National Wind/Photovoltaic/Energy Storage and Transmission Demonstration Project, we investigated the ability of WSSPS providing auxiliary services by analyzing their real characteristics. Then, under the guidance of the North China Bureau of SERC, we studied the trading mechanisms from two cases respectively: no-restriction on generating electricity or restriction on generating electricity.When no-restriction on generating electricity, wind farms must launch the work of wind power forecasting according to the requirements, but the wind farms often will be assessed because theirs power forecasting accuracy can’t reach the assessment standard. Combined with the characteristics of WSSPS and wind farms, this paper designs a service mechanism that WSSPS helps wind farms tracking generation schedule curve, in order to improve the power forecasting accuracy of wind farms. And based on the trading mechanism, we establish a control strategy model of output compensating actions to make efficient use of the regulating ability of WSSPS.Examples are given verified that the trading mechanism not only can achieve mutually beneficial and win-win of transactions, but also reduce the impact on the grid caused by fluctuations of wind power’s output.When restriction on generating electricity, wind farm must generate electricity according to generation schedule curve given by dispatching agency, but the transfer passage of wind power may be underutilized in real operation because the insufficient output of wind farm caused by their own reasons. This article introduces the guidance of wind power forecasting and the encouraging of market mechanism into the distribution of wind channel, and designs a day-ahead trading mechanism of power allowances’ surplus of the wind farms based on wind power forecasting. Next, we set up trading strategy models for buyers and sellers of power allowances’ surplus based on theirs day-head wind power forecasting. Examples are given to indicate that the trading mechanism is practicable and the trading can increase the yield of participants and improve the efficiency of wind channel, also affirms that the trading mechanism can be practically used in the situation of the wind curtailment of our country.