Research On Comprehensive Benefits Of DG And Its Expansion Planning

With the development of social economy,the problems such us:energy issues，rapidly increasing of load demand and reliability of power supply requirement hasappeared。 Duing long construction period, poor ability to load track, seriousenvironmental pollution and other shortcomings，the traditional power generation isdifficult to satisfy the required of high quality and reliable electricity. DistributedPower (Distributed Generation, DG) is a new type of renewable energy which hasadvantages of load tracking capability, flexible power generation, low investment andconstruction costs, less environmental pollution and high reliability of powersupply.So DG can be a best supplement.But our use of distributed generationtechnology is still in its infancy, If we can scientifically assess the economic benefitsgenerated by DG and give a reasonable plan for the distribution network consideringDG，this will be help to guide the power companies, investors and policy-makingdepartments to better develop distributed generation technologies。 Therefore，In thispaper, the problem about the distribution network planning considering DG and thecomprehensive benefits generated by DG are researched。First，This paper introduces the concept, classification and current research statusof DG, meanwhile, analyzed the common typles of DG and its generation principles.Secondly,it quantitatively analyzed the benefits of DG for reducing line losses,decreasing power purchase cost, improving the environment, enhancing the reliabilityof power supply and others.Then, established the benefits quantitative model。In termsof reducing the cost of purchase of electricity，it considered the effect of the gradientTOU, energy tax and used the multiple price method to assess the reliability of powersupply。Appropriately selected the location and power of DG can effectively reducesystem line loss, pollution, environmental expenses and users of power loss。In thepeak and normal hours of second and third gradient access the DG can reduce the usercost of power purchase. If the DG is used as power supply and power generation,itcan not only avoid paying the taxes of energy,and climate change.but also provide atheoretical reference for the development of DG..Finally, It considers the benefit of distribution, generation and users, constructs adistribution network optimal model which makes the annual fee, the maximum offsetvoltage, power purchase and environmental costs are minimized,then it proposes theoptimal solution. With the objective function added to penalty factor,it changes the multi-objective optimization problem into the single problem. For the disadvantagesof traditional genetic algorithm and adaptive genetic algorithm, Moreover，Fuzzytheory can be used in genetic algorithms，if the control parameters of crossover andmutation rates are fuzzy control it can improve the genetic algorithm optimizationcapabilities.In the end,the example demonstrates the feasibility of the model and thesuperiority of the algorithm.