Research On Optimal Configuring Of Passive Power Filters In Distribution Network

Power electronics device plays a main role in the harmonic sources and harmonic distortion has experienced a continuous increase in distribution systems owing to the growing use of it. Restraining harmonic distortion can improve security and reliability of the equipment, and plays an important role in secure and economic operation of power system. Simultaneously, distribution information management system based on web becomes a trend of information technology.As essential calculations in optimal configuring of filters in distribution network, harmonic power flow calculation is the tool of further research on restraining harmonic distortion. A node-branch incident matrix algorithm is proposed. In this algorithm, through the optimizing numbering of nodes, corresponding node-branch association matrix is established, back forward sweep calculates, which improves the calculation efficiency greatly. Then, utilizing the decoupling of fundamental power flow and harmonic power flow, the result of distribution system harmonic power flow is got by direct method.The most important method of restraining harmonics is to configure passive power filters because it is simple configuration, convenient maintenance, low cost and etc. The characteristic that multiple harmonic source loads lie in distribution network is more prominent. Aim at this kind of situation, the optimum placement of different order's filters can be derived from the inherent structure theory. By establishing the different order's harmonics nodal admittance matrixes and computing the corresponding sensitivity matrixes, considering the relationship between the power system structure's changes and the system status, the candidate nodes of the optimum placement of different order's filters can be derived. The design of the filter parameter is very important to restrain harmonics, On the base of making analysis of the classic of method, this paper proposes a new strategy to optimal passive filter performance by the artificial immune algorithm. To meet the harmonic voltage distortion limits and security constraints with a minimum total investment cost. Compared with genetic algorithm, immune algorithm is avoided to fall into local optimum to keep the multiform of the antibody.Finally, Internet is introduced to this system. Web server use ASP technology, set up an integrated server environment through IIS (Internet Information Servers), use ADO to visit target's database. Programs (such as harmonic suppression algorithm and the placement of filters) are developed through VB in applied server. This system realizes that the result and distribution network topology examine remotely.The method in this dissertation can effectively suppress harmonic distortion, and have offered the new application platform for information sharing and studying synthetically of the big range.