Research On Certain Issues In Distributed Power System

Several problems related to the distributed power system are studied in this paper.According to the fluid network theory and the defined evaluation method, the stability index Ks can be deduced. And it can be calculated to compare the stability of the central power system and the distributed power system quantitatively. Results show that the change of power affects the stability of system. Some branches have a poor performance on adjustment, and therefore the power cannot be simply distributed.The stability of distributed power system can be improved by decreasing the resistances of main pipes and increasing the resistances of branches. Pump characteristic curve also have an influence on stability that flat characteristic curve of main pump and steep characteristic curve of branch pump is the optimal combination. Stability of the regulation mode with fixed zero-pressure-difference point is better than that with variable zero-pressure-difference point.In order to avoid the waste of energy, the zero-pressure-difference point should be between the heat source and the critical point. And wherever in that region, the energy consumption is the same lowest. The match schemes of pump head are not single, which are correspondent with the zero-pressure-difference point. Based on the numerical method, Microsoft Visual C++software can be used to solve the pump head of distributed power system. And it is the most advantageous for the whole stability of system to have the zero-pressure-difference point stay in the middle of network.A air-conditioning water system has been taken as an example. Three transmission schemes are put forward and their economic calculation are analyzed. Results show that although the variable frequency equipments increase the initial investment, operating cost of pumps is saved a lot. Therefore, money can be withdrawn in the life cycle of pump. If the system is often in partial load condition, and the resistances of loops have a huge difference, the third scheme of distributed power system is economical.