Research On Integrated Market Clearing Model Of Reactive Power Ancillary Service Based On The Coordination Of Transmission And Distribution Network

The active distribution network（ADN）can provide reactive power ancillary service（RPAS）to improve the operations of the transmission network（such as voltage control,and network loss reduction）as distribution generation grows.In this context,an RPAS market is required to motivate the ADN to provide RPAS to the transmission network since the transmission system operator（TSO）and distribution system operator（DSO）are different entities.For the above problems,the reactive power optimization model of distribution system based on photovoltaic（PV）inverter regulation is established by the structure characteristics of radial distribution network with distributed PV power supply,the renewable energy integration’s influence on distribution system’s reactive power flow and voltage distribution is studied.On this basis,the RPAS integrated market clearing model and framework based on the coordination of transmission and distribution network are constructed,and further explore the impact of TSO and DSO cooperation mode and role conversion in the power market on the market clearing results and system operation economy.The main research contents are as follow:（1）In view of the impact of large-scale renewable energy integration on the power system’s safe operation,a reactive power optimization model of distribution network based on PV inverter regulation is established.Firstly,the mathematical model of PV and PV inverter’s reactive power capacity are introduced.According to the radial distribution network’s structural characteristics,the alternating current optimal power flow（ACOPF）model of radial ADN is established,and the second-order cone（SOC）relaxation technology is used to convexize the non-convex equation in the model.Finally,the IEEE 33-node distribution system is taken as an example to verify the effectiveness of the proposed model,the PV inverter’s reactive power regulation ability is demonstrated,and the reactive power regulation ability of PV inverter is shown.（2）To promote the coordination and cooperation between TSO and DSO,several common TSO-DSO ancillary service（AS）market frameworks are introduced,and an integrated market clearing framework and market clearing mechanism including the sequential clearing of day-ahead energy market and RPAS market based on the coordination of transmission and distribution network are proposed.According to the proposed market clearing mechanism,the day-ahead energy market clearing model and RPAS market clearing model using the coordination of transmission and distribution network are established.Finally,the non-convex bilinear terms in the objective function of the model are linearized by Binary expansion（BE）.（3）Based on the principle of distributed optimization method,a general consistency optimization model based on Alternating direction method of multipliers（ADMM）is introduced.On this basis,the method is applied to the proposed market model,and the day-ahead energy market clearing model and RPAS market clearing model based on ADMM general consistency algorithm are established.Finally,the T5-D33 test system composed of a modified PJM-5 node transmission network and three modified IEEE33-node distribution system and the T30-D33 test system composed of a modified IEEE30-node transmission system and three modified IEEE33-node distribution system are respectively analyzed.The effectiveness of the model is verified,and the proposed model can improve the economic benefit of ADN and reduce the total operating cost of power system under the premise of ensuring the privacy of TSO and DSO information.