Introduction
Power System Development Plan refers to the development and construction plan of power system within 5 - 15 years. Electricity System Development Plan is also known as power system design in China. Its content includes: electricity load prediction, power resources development, power development planning, power network development planning. Propose power system geographic wiring diagrams, single-line wiring diagrams, and year-on-year engineering construction project tables. In addition, it is designed for power plant design, substation design, power system relay protection and safety automatic device design, power system communication design, and power system scheduling automation design. Mid-term development plan is based on long-term development planning, subject to its constraints and guidance. In the past, the interim development plan was 3-5 years, sometimes out of 7-10 years. Since the length of planning years is related to the size of the system and the country where the power system is located in the region of the Ministry of China. It is often long, and the current development plan of the power system is now long. More than 5 - 15 years. Amendment once a year, rolling annual year. China Electric Power System Design. Often a five-year plan or ten-year plan for the country, from 5-10 years, looking forward to 15 years.
Power load prediction
The development value of future load is measured according to the national economic development plan of the power system and the future production and construction planning planning plan. It is the basis for hair, loss, distribution construction planning and economic analysis. The prediction content is:
1 load value. Includes the maximum and minimum load and annual capacity of the summer year by year.
2 load characteristics. Includes representative days, year and annual continuous load curves, winter, summer daily load rate. The minimum load rate and month imbalance rate.
3 of each division area load. Due to the uncertainty of load forecasting. Therefore, it is also necessary to consider the effects of different load levels on the planning of the cold and power system. That is, sensitivity analysis is performed.
The power load level reflects the development of the national economy and society. Therefore, when the high-side load, we must first investigate the national economic development. Research and development law. Approval load predictive value. Load prediction method useful electrical unit consumption, time-to-time method, regression analysis method, and power elastic coefficient method.
Power Resources Development
Power Resources Development Research 5 - 15 years in the development and utilization of power resources, implementing a possible energy supply within the planning period. To meet the needs of electricity load, The medium-term development plan should analyze the supply of coal, hydraulic, oil, natural gas and nuclear energy according to the characteristics of energy policies in the country, and the possibility of purchasing energy, and to analyze the supply of coal, hydraulic, petroleum, natural gas and nuclear energy. Implementation, oil, natural gas and nuclear energy supply plan clear. If there are several possible supply programs in the region, the analysis is compared. From the medium selection, it has achieved the purpose of only the energy demand and reasonable use of power resources, from the 1970s, some countries have studied the energy model. After entering data such as energy, electric load and economic indicators, the best energy supply can be obtained, but due to the imperfect model. The data is difficult to accurately, so there is still a variety of ways to measure, and after a comprehensive comparison, a relatively reasonable solution can be obtained.
Power Development Plan
Power Development Planning Research 5 - 15 years of power construction arrangements, proposing projects, capacity and construction progress of power construction. The content is: 1 total power capacity arrangement; 2 determination of spare capacity; 3 power generation capacity composition and function analysis.
Power Generation Composition and Function Analysis Power Plant According to the energy type used, there is a hydropower plant, thermal power plant (coal-fired, oil or gas) and nuclear power plants. The medium-term development plan of electricity system should determine the most energy economy development plan from regional energy resources, through technical and economic comparisons. Select reasonable composition of power generation capacity. Since the 1960s, countries have developed some power optimization mathematical models. These models can be optimized to optimize the power supply in power system expansion. However, because some models belong to single-node power supply planning, there is no considering power supply and load geographic distribution factors, some have not fully considered hydrological characteristics of hydropower, and some do not include economic evaluation of power generation technology. Therefore, these models still have to be further improved.
Power Network Development Plan
Power Network Development Planning includes transmission network development planning and distribution network development planning two parts
Transmission network development planning research 5 ~ 15 years The optimal connection scheme between the power system and the adjacent power system is to study the voltage level of the power system. The structure of the power system, etc. to meet the basic requirements of the reliability, economic and flexibility of the power system. To this end, various technical conditions must be calculated. For example, it is necessary to perform trend calculation and analysis. Calculation and analysis of non-power balance and phase modulation regulation and analysis of system stability. The short circuit current calculation analysis, frequency over voltage and sub-supply current calculation analysis. And the reliability of transmission, based on this. After the economies are compared, choose the best solution. When planning a super high voltage power system, it is also considered to consider the impact of the line trail and the location of the substation. Such as corona, electromagnetic field, audible noise, radio interference, etc.
Power supply planning research 5 - 15 years of power supply development planning, distribution network development plan is based on the level of future load prediction, from the transformation And strengthen the existing city network into the hand, reasonably select the power supply, voltage level, urban network wiring and reactive compensation and voltage adjustment measures. Load distribution map, city network geographic wiring diagram and single-line diagram and reserved corridor and address for lines, substation. The power selection is based on the principle of power construction in the mid-term plan, considering the urban network load density size and site conditions. Usually the type and capacity of urban power supply is determined by medium-term development plan, and the specific choice of power supply. Then, the city network is planned, and the power supply should consider sufficient reliability. When a power supply is powered off due to accidents, the remaining power supply should still guarantee power supply, the power supply should be as close as possible to the load center, the city network supply voltage, the situation is different, but it is generally simplified as possible. High-voltage power transmission voltages of enterprises in various countries are also different, such as Chicago, USA.
summary
The development plan of rural distribution network is the same as the development plan of urban distribution network, but the load density is low, and the electric load is compared. In the rural areas of agricultural electricity, the seasonal electricity load is large, and the countryside has a large countryside. Its electricity is the same as the city, and the distribution network is also substantially the same.