多种新能源接入的地区电网无功电压控制研究

发布时间：2018-06-27 08:11

本文选题：新能源 + 地区电网　；参考：《华北电力大学(北京)》2017年硕士论文

【摘要】：随着社会经济的快速发展,我国对能源的需求与日俱增,但化石能源日趋枯竭,核能发展受到限制,以煤炭、石油为主要能量来源的传统发电模式正面临资源可持续利用、气候变暖以及环境污染等一系列问题,这使得可再生能源的开发和利用逐渐成为社会可持续发展的必由之路。然而,大量新能源厂站分布式接入改变了电网中各支路潮流的流动特点,从而改变了电网的电压分布,且分布式电源的出力具有较强的随机性,会导致并网点电压波动,容易造成电压越限等问题;另外,现有电网调压的方法主要依靠投切电容器和调节变压器分接头,并未充分利用分布式新能源厂站的无功调节资源,分布式电源出力的波动性易引发常规厂站无功设备频繁动作、反复调节等问题,影响电网及设备的安全运行。所以需要进一步加强多种无功资源的协调控制,完善电网分层分布式的无功电压控制模式,保证分布式电源并网后电网的优质、经济和安全运行。基于此,本文做了以下研究工作。(1)分析了新能源接入对地区电网无功电压的影响。以某包含风电、光伏、小水电等多种新能源接入的地区电网为例,分析了新能源接入地区电网无功源的特点和新能源功率流动对节点电压的影响;针对不同负荷特性,仿真分析了不同新能源接入电网对PCC点电压的影响。(2)分析了不同无功电压控制手段的效果分析。考虑不同负荷模型,研究了改变变压器变比和无功补偿量对PCC点电压和功率因数的影响;以风电场为例,研究了新能源厂站无功电压控制手段对PCC点电压和功率因数的影响。(3)提出了单时间断面的无功电压优化。研究了新能源厂站的无功电压控制策略,构建单时间断面的无功电压优化控制模型,并进行了仿真分析。(4)提出了一种时序递进的含风电、光伏、小水电等多种新能源接入的地区电网无功电压优化控制方法,进行日前、日内到实时多时间尺度的协调优化控制。优化过程中基于综合负荷变化趋势进行分时段多目标优化,计及离散调节设备的日调节次数限制,仿真验证了该方法的有效性。
[Abstract]:With the rapid development of social economy, the demand for energy is increasing in China, but fossil energy is exhausted day by day, and the development of nuclear energy is restricted. The traditional power generation mode with coal and oil as the main energy source is facing the sustainable utilization of resources. A series of problems, such as climate warming and environmental pollution, make the development and utilization of renewable energy gradually become the only way to the sustainable development of society. However, the distributed access of a large number of new energy plants and stations changes the flow characteristics of each branch power flow in the power network, thus changing the voltage distribution of the power grid, and the distributed power generation has a strong randomness, which will lead to the voltage fluctuation of the parallel network. In addition, the existing methods of voltage regulation mainly rely on switching capacitors and regulating transformer tap, and do not make full use of reactive power regulation resources of distributed new energy plants. The fluctuation of distributed power generation will easily cause frequent movement and repeated adjustment of reactive power equipment in conventional power plant and station, which will affect the safe operation of power grid and equipment. Therefore, it is necessary to further strengthen the coordination control of various reactive power resources, improve the hierarchical and distributed reactive power and voltage control mode, and ensure the high quality, economic and safe operation of the grid after the distributed power generation is connected to the grid. Based on this, the following research work is done in this paper. (1) the influence of new energy access on the reactive power and voltage of regional power network is analyzed. Taking a regional power network which includes wind power, photovoltaic, small hydropower and other new energy sources as an example, the characteristics of reactive power source and the influence of new energy power flow on node voltage are analyzed. The influence of different new energy sources on PCC point voltage is analyzed by simulation. (2) the effect of different reactive power and voltage control methods is analyzed. Considering different load models, the influence of changing transformer variable ratio and reactive power compensation on PCC voltage and power factor is studied. The influence of reactive power and voltage control methods on PCC point voltage and power factor is studied. (3) the reactive voltage optimization of single time section is proposed. The reactive power and voltage control strategy of the new energy plant station is studied, the reactive power and voltage optimal control model of single time section is constructed, and the simulation analysis is carried out. (4) A sequential progressive wind power and photovoltaic system is proposed. The optimal control method of reactive power and voltage in regional power network with multiple new energy sources such as small hydropower is coordinated and optimized from day to day, from real time scale to multi-time scale. In the process of optimization, the multi-objective optimization is carried out based on the trend of comprehensive load variation. The effectiveness of the method is verified by simulation, considering the daily regulation times of discrete adjustment equipment.
【学位授予单位】：华北电力大学(北京)
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM761.12

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