【作者】 崔秀玉；

【导师】 杨俊华；

【作者基本信息】 广东工业大学 ， 控制理论与控制工程， 2007， 硕士

【摘要】 随着我国城乡电网改造，对配电网建设的越来越重视和无功补偿技术的发展，低压侧无功补偿技术在配电系统中也开始普及，从静态补偿到动态补偿，从有触点投切到无触点投切，都取得了丰富的运行经验。目前无功补偿控制装置控制物理量主要有：无功功率控制、功率因数控制以及电压、无功综合控制。从控制策略来看，无功功率控制或电压、无功综合控制的控制器控制比较合理，而采用功率因数控制虽比较简单明了，但如不采取相应措施，则可能产生投切振荡问题。首先从理论上分析了电力系统无功功率平衡和电压调整关系，对目前各种电压调整手段优缺点进行了比较，重点探讨了典型电压无功调整装置(VQC)的控制策略，结合所从事电网运行和管理实际工作经验，指出目前多数电压无功补偿控制装置的控制策略不完善，没有进行优化，主要表现在变压器分接头和补偿电容器调整次数过多、影响设备寿命和安全以及负荷波动时的投切振荡问题。提出将超短期负荷预测引入变电站综合调压，重点在综合调压控制策略的优化上进行了深入研究。首先对变压器分接头调节和补偿电容器投切控制策略进行优化，充分利用二者的优势，实现优化的综合调压；其前提是必须能判断负荷波动的情况，掌握负荷变化趋势。因此，一种可行的方法是采用超短期负荷预测的控制策略，基本思路是建立一种闭环控制，将实际负荷同预测曲线相比较，通过优化计算，判断是否投切电容器和调整变压器分接头，并充分利用变压器的过负荷能力，从而达到综合优化的目的。准确的电力系统超短期负荷预测是实现上述方法的前提和基础，比较了各种负荷预测方法，分析了负荷特点和变化规律。为提高预测精度和智能化水平，采用人工神经网、一元线性回归法和指数平滑法相结合的综合短期负荷预测方法。具有较强的学习、计算、变结构适应、复杂映射、记忆、容错及各种智能处理能力，能很好的适应负荷变化，计算精度高，能满足实际需要。在上述研究成果的基础上，建立了无功补偿实时控制解决方案，给出了系统框图，对典型电压无功控制装置从控制策略上进行了优化，做了软件和硬件的改进工作。该方法不仅能提高变电站母线电压合格率和功率因数，同时有效地减少了开关操作次数，延长了设备寿命，减少对系统安全的影响。更多还原

【Abstract】 With the reform of power system and the development of reactive compensationtechnology, reactive compensation technology on the low voltage side has becomepopularized. Both from static compensation to the dynamic compensation and contactthrow-cut to without contact throw-cut have got rich operation experience. At present,the reactive compensate control is mainly on reactive power control, power factorcontrol, and reactive power synthetically control. Taking the control strategy intoconsidered, the reactive power control, the reactive voltage synthetically control ismuch reasonable. Although power factor control is comparatively simple, there willproduce throw-cut vibration without relevant strategy.Theoretically analyzes have been done to the relations between reactive powerbalance and the voltage regulation of electrical power system. It compares all kinds ofvoltage regulation method’s advantages and disadvantages, and mainly discussed thecontrol strategy of typical reactive voltage adjusting device. With the practicaloperation experience and management experience on electrical network, this paperpointes out that most of the reactive voltage control strategies are imperfect, whichhave no optimization and too many transformer tapping and too many compensationcapacitor adjustment, this influences the equipment life and the security, also causesthe throw-cut vibration with the load fluctuation.The super-short-term load forecasting to voltage synthetically adjusting has beenintroduced mainly on control strategy optimization of synthetically voltage adjustment.Firstly, carrying out an optimization on control strategy of the transformer tappingadjustment and compensates capacitor throw-cut, fully using two superiority to realizeoptimized synthetically adjustment voltage; but the premise is that it can judge the loadfluctuation and grasp the load change tendency. Therefore, one feasible method is touse the control strategy of the super-short-term load forecast. The basic way is toestablish one kind of closed-loop control, comparing the actual load with theforecasting curve, by the optimization calculation, judging whether throw-cut thecapacitor and adjustment transformer tapping, and fully uses the overload ability of thetransformer, thus achieves synthetically optimization’s goal.The accurate forecast of electrical power system super-short-term load is thefoundation of the realization of the above method. This paper has carried out thecomparison of each load forecasting method, analyzed the load characteristic and thechange rule. In order to increase the precision of load forecast and the intellectual level,we used the synthetically super-short-term load forecast method of the artificial nervenetwork and once basic linearity return, index smoothing method. It has stronglearning capability, calculating capability, changing structure adaptive capability andother characteristics. It can adapt load change well, and meet the actual needs.A real-time control of the compensation capacitor solution according to the abovewas presented; the system diagram also was given, and has realized this method using the hardware. This method can not only enhance voltage qualified rate of thesubstation generatrix and power factor, simultaneously effectively reduced the switchoperation number of times, lengthened the life of equipment, and reduced the influenceof the system security.更多还原