Power generation plan considering priority generation under power spot market environment

1. Research on generation planning methods under market environment

1.1 Power generation plan verification principles

Under the market environment, the power generation plan adheres to the following principles:

First, give full play to the role of planned electricity to ensure the power supply of non-market users, coordinate the profit distribution of market players, and ensure the survival of power generation enterprises and capacity investment recovery;

Second, adhere to the implementation of the priority power generation plan, ensure the grid voltage support and peak frequency regulation needs, and fully ensure the safe and stable operation of the grid;

Third, the high price of planned electricity fully guides power users to participate in market transactions;

Fourth, pay attention to the planned power and market power coordination, power generation plan formulation and distribution methods should be easy for market players to understand and accept, to achieve an orderly transition from the plan to the market.

1.2 Verification method of planned electricity

In accordance with the principle and method of "determining power generation by use", the spot market of Guangdong Power has realized the matching of market power generation and power consumption, which has largely suppressed the adverse effects of unbalanced accounts caused by the parallel dual-track system [6]. However, with the continuous opening of the market scale, the inherent defects of the mechanism of "using fixed hair" are gradually exposed.

Before the capacity market is built, the planned electricity mainly bears the multiple roles of ensuring the investment recovery of power generation enterprises and non-market user electricity consumption, voltage support, peak regulation and frequency regulation demand (that is, priority power generation), so the planned electricity should be approved separately.

If the market transaction comprehensive contract price is higher than the medium - and long-term contract average price, there is no additional verification of guaranteed investment recovery electricity for the current year. For provinces that have not yet carried out spot market trading (control areas), there is no additional verification of investment recovery power. Investment recovery electricity rate verification, further smooth the impact of energy market price fluctuations on the income of power generation enterprises in the previous year, avoid power generation enterprises to blindly declare high prices for corporate earnings, and help the market main body to return to rationality.

Formula (2) Fully ensures that the annual planned power generation scale does not exceed the annual total power consumption of non-market users, and on the basis of ensuring the survival of power generation enterprises, provides the possibility and feasibility of realizing the matching of power generation institutions by adjusting the power plan. The power plan of each power plant is

1.3 Generation plan formulation process

As it is difficult to accurately control the boundary conditions and power consumption characteristics of the power grid in the coming year, the calculation and determination of the annual planned total amount of electricity and annual priority power generation may not be accurate. Therefore, it is necessary to adjust the power plan during the year, increase or reduce the planned power of each power plant according to the deviation between the actual demand for priority power generation and the predicted value of priority power generation, improve the matching degree of non-market power generation and market power generation, and alleviate the imbalance of market settlement.

1.4 Method of monthly decomposition of power generation plan

Under the market environment, the electricity component of the annual electricity plan of the power generation enterprise includes the planned electricity and the market electricity, and its monthly decomposition method.

There are two main monthly decomposition methods of market electricity: the trading contract determined by bilateral negotiation over the counter, and the buyer and seller determine the monthly decomposition amount of the annual contract through negotiation; Trading contracts determined by centralized matching and listed trading on the floor, and the monthly trading power is determined by the market support system.

The annual priority power generation is divided into each month according to the monthly approved priority power generation to ensure the electricity demand of non-operational users and the safe and stable operation of the grid; Investment recovery electricity and untraded market transaction electricity are decomposed into each month based on the preferential power generation of each month as a proportional coefficient.

2. Analysis of numerical examples

2.1 Example description

In terms of load level and spot market price mechanism, the load level and TOU price level of the day ahead market and real-time market are shown in Table 1. In order to simplify the analysis, the power curve of four sections per day is used in the example: the load level is the same at 0~6, the load level is the same at 7~12, the load level is the same at 12~18, and the load level is the same at 19~24.