Research On Distribution Network Loss Allocation Method With Small Hydropower Groups Under The Background Of Electricity Market

In an era when clean energy is being vigorously developed,small hydropower,which is green,clean and low in cost,has developed rapidly.However,the loss allocation of distribution network with small hydropower is more complicated.Therefore,this paper studies the distribution network loss allocation problem with small hydropower groups to provide a scientific,reasonable and fair method for distribution network with small hydropower groups in the electricity market.Firstly,aiming at the problem that the marginal loss coefficient method depends on the selection of balancing nodes and the balancing nodes do not allocate network losses when allocating network losses Therefore,this paper adopts the branch dissipation power transfer component method to make up for the defect that the marginal loss coefficient method does not include the balanced nodes in the loss allocation range.From the perspective of electromagnetic field and circuit,the branch dissipation power transfer component method based on energy flow density is derived.The branch dissipation power transfer component method and marginal loss coefficient method are combined to study the distribution network loss allocation with small hydropower groups.Then,in the process of network loss allocation,the possible influence of key factors such as reverse power flow,cross problem,transaction joining order and reactive power flow on network loss allocation is considered,etc.,and respectively conducts modeling and simulation analysis on the above factors,and the simulation results show the necessity of considering the problem.In addition,this paper also considers the maintenance problem of small hydropower units and the influence of the location of small hydropower in the system on network loss allocation,establishes the models of the two and makes simulation analysis,and formulates a reasonable generation plan and unit maintenance plan aiming at the maintenance problem and minimizing the network loss.Finally,a case study of a power grid in Gansu Province is carried out by using the branch dissipation power conversion component method and marginal loss coefficient method,and compared with the traditional improved average loss allocation method.The comparison results show that the loss allocation method adopted in this paper can better reflect the requirements of loss allocation in the power market and is easy to be accepted by all market participants.It can not only provide economic signals for all investors,but also make the allocation process more transparent and the allocation results fairer.Moreover,power flow calculation is used to verify the branch dissipation power transfer component method and marginal loss coefficient method adopted in this paper.The results show that the method used in this paper is more in line with the actual flow,which shows that the accuracy of the method used in this paper is better.