The Device Research And Application Of Distribution Transformer For Power Quality Comprehensive

With the development of power system,the load type of distribution network is becoming more and more complicated,and the non-linear load is increasing.The power quality problems,such as three-phase imbalance,reactive power shortage and harmonic will cause the additional loss of distribution transformer,and shorten the service life.The compensator of traditional distribution transformer usually uses the capacitor to solve the problem of reactive power shortage,but cannot solve including the three-phase imbalance and harmonic power quality problems.In allusion to the power quality problems in distribution area,a unified power quality conditioner of distribution transformer is researched and designed to solve or alleviate the above problems.This paper introduces the working principle of the unified power quality conditioner,and establishs a mathematical model under the stationary coordinate system abc.In allusion to the power quality problems,this paper designs a compensation allocation link based on the characteristics of power quality by means of comprehensive evaluation of power quality.Moreover,this paper analyzes and compares the advantages and disadvantages of traditional compensator control strategy,researches real-time compensation current detection method and current tracking control method,and proposes a compensation control strategy which is suitable for distribution area and project application by combining with the compensation allocation link.Based on the relevant theoretical researches and the simulation model is built with simulation software Matlab2013 a,the simulation results verify the effectness of the compensation control strategy proposed in this paper.This paper calculates the addition loss of the distribution transformer running in the condition with three-phase imbalance,reactive power shortage and harmonic and other power quality problems,calculates the loss of unified power quality conditioner,then analyzes by means of the calculation method of this paper,and compares the loss of the unified power quality conditioner before and after putting into operation.The calculating data shows that the study of paper has the effect of energy saving and reducing loss.Based on the above work to complete the hardware and software for the prototype of unified power quality conditioner of distribution transformer,and conduct charging test,the test data shows the correctness of the compensation strategy,In addition,the unified power quality conditioner puts into operation in the pilot area,the data by monitoring the background output data of distribution transformer indicates that the device is effective in improving the power quality of the distribution area in engineering applications.