Study On Frequency Modulation Of Wind Solar Complementary Microgrid Considering Demand Side Resources Participation

Frequency control is very important for the microgrid which operates independently.Good frequency error is the main index to evaluate the operation quality of micro grid.With people's increasing attention to green environmental protection and energy conservation,new energy can develop rapidly.The single new energy generation has great randomness and uncertainty.To some extent,the multi energy complementary generation can effectively increase the reliability of microgrid power supply and improve the frequency quality of the system,of which the wind solar complementary microgrid is the most typical.In this paper,household constant frequency air-conditioning and wind solar complementary micro grid are taken as the research object.From the two aspects of aggregation modeling and optimization of air-conditioning load,demand response control strategy of air-conditioning polymer,this paper studies demand side resources participate in microgrid frequency modulation.First of all,starting from the working principle of home air conditioning,according to the law of energy exchange,combined with indoor and outdoor temperature,the equivalent thermal parameters(ETP)model is established.Through comparative analysis of the advantages and disadvantages of different order models,the first order equivalent thermal parameters ETP air conditioning model is selected finally.Through Monte Carlo mathematical simulation method,the load aggregation of single air conditioning model is carried out,and the load polymer of air conditioning is constructed.The power constraint conditions of air conditioning polymer are derived according to the requirements of human comfort.Aiming at the problem of large power fluctuation in the adjustment process of air conditioning polymer,an improved temperature control method of air conditioning load is adopted to eliminate the load fluctuation in the adjustment process,optimize the response of air conditioning polymer,improve the accuracy of polymer response,and lay the foundation for the subsequent demand response research.Secondly,in view of the problems existing in the traditional centralized response control and decentralized response control schemes,on the basis of previous research,considering the distributed response control,combined with the traction control idea,a demand response strategy of air conditioning polymer based on distributed traction consistency control is proposed.Through a virtual leadership polymer,a global constraint variable is introduced into the demand response side,and the global constraint variable is only issued to some air conditioning polymers.The other air conditioning polymers ensure the fair participation of multiple air conditioning polymers through the interaction and coordination of adjacent information,so as to achieve the optimal power distribution response of the demand side under the global constraint.And the internal control structure of the virtual leadership polymer is established.In the simple micro-grid model,the convergence of the traction load rate of the air conditioning polymer under the control of the distributed traction protocol and the effectiveness of participating in the frequency modulation for the realization of the system frequency adjustment without difference are verified.Finally,based on the traditional primary and secondary frequency modulation principle,the frequency modulation principle of the demand side participating in the micro grid is analyzed,and the frequency modulation control process of the micro grid with the participation of air conditioning polymer is formulated.Furthermore,the demand response frequency modulation module is established,and the system frequency modulation model of air conditioning polymer group participating in the wind solar complementary micro grid is built in matlab / Simulink.Among them,turbine generator set is added to the wind solar complementary micro grid to serve as the basic frequency modulation reserve of the system,and set reasonable load disturbance.The simulation shows the impact of new energy generation on micro grid frequency and verifies the complementarity of wind and solar power generation in time.At the same time,it further verifies the effectiveness of air conditioning polymer participating in frequency modulation of micro-grid based on distributed traction consistent response control strategy,and improves the stability of microgrid operation frequency.