直流微电网能量优化控制研究

发布时间：2018-01-07 16:04

本文关键词：直流微电网能量优化控制研究　出处：《西南交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：最近几年,世界范围内连续发生了几次造成重大影响的停电事故,这充分地暴露了大电网的脆弱性。分布式发电(Distributed Generation, DG)的种种优势使其得以成为电力系统的发展趋势之一,但它还存在许多问题,如单机接入成本较高、控制难度较大等。为了减小DG对大电网的冲击,需要在使用时对DG进行限制或隔离等处理,因此DG效能的充分发挥受到了严重的限制。研究人员提出了微电网这一概念,希望以此来协调大电网与DG之间的冲突、充分利用DG。微电网通过将微电源、负荷、储能设备和控制装置整合起来,形成可控、独立的供电系统,充分利用系统中的DG,其运行模式灵活,但控制策略上有较高要求。微电网具有双重作用,对大型电力网络来说,它被当做一个以数秒速度响应外部网络能量需求的可控单元；另一方面,从用户角度来说,微电网可以满足不同用户对电能的特殊需求,提供多样化的电能。本文研究了DG最大功率点跟踪、蓄电池双向DC/DC变换器控制以及直流母线能量优化控制三个方面。主要工作有： 1、基于风力发电Matlab仿真模型,分析了风力发电机的输出特性,并采用占空比扰动法实现了风力发电的最大功率跟随。 2、基于光伏电池Matlab仿真模型,仿真验证该模型可以准确地模拟光伏电池的输出特性。提出一种基于功率预测的变步长扰动最大功率点跟踪方法,并仿真验证其有效性。 3、基于蓄电池充放电Matlab仿真模型,仿真验证双向DC/DC变换器充放电控制策略。 4、提出了一种直流母线能量的优化利用方法,通过协调控制各微源工作在最大功率点跟踪模式或母线电压跟踪模式来提高母线能量利用效率,以风光联合发电系统为例进行了仿真验证,并与各微源独立进行最大功率点跟踪对比,验证了该方法的有效性。
[Abstract]:In recent years, the world has undergone several times affect the power outage, this fully exposed the vulnerability of large power grid. Distributed generation (Distributed Generation, DG) of the various advantages to enable it to become one of the development trend of the power system, but it also has many problems, such as the high cost of computer access it is difficult to control, and so on. In order to reduce the impact of DG on power grid, to restrict or isolation of DG DG in use, so its efficiency is limited seriously. The researchers put forward the concept of micro grid, hoping to coordinate the conflict between the grid and DG, make full use of DG.
Micro power grid through the micro power, load, energy storage device and control device are integrated to form a controllable, independent power supply system, make full use of DG system, its operation mode is flexible, but the control strategy has high requirements. The micro grid has a dual role of large power network, it is used as a the number of seconds the response speed controllable energy demand of the external network; on the other hand, from the user perspective, the micro grid can meet the special needs of different users of electricity, offers a variety of electrical energy.
In this paper, the maximum power point tracking of DG, the control of bi-directional DC/DC converter and the optimal control of the DC bus energy are studied in three aspects.
1, based on the Matlab simulation model of wind power generation, the output characteristics of the wind generator are analyzed and the maximum power following of the wind power generation is realized by the duty cycle method.
2, based on the photovoltaic cell Matlab simulation model, simulation results show that the proposed model can accurately simulate the output characteristics of PV cells. A variable step size disturbance maximum power point tracking method based on power prediction is proposed, and its effectiveness is verified by simulation.
3, based on the Matlab simulation model of battery charging and discharging, simulation and verification of the charge and discharge control strategy of bidirectional DC/DC converter.
4, we propose an optimized DC bus energy utilization method, through the micro source tracking mode or voltage tracking mode to improve the bus energy efficiency at the maximum power point control, the scenery combined generation system is validated, and the micro source of independent of the maximum power point tracking contrast. To verify the effectiveness of the method.

【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM727

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