Study On Integrated Voltage Adjustment Based On Super Short Time Load Forecast In Substation

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.