Research On Setting Adjustment Of Setting Calculation Software For Relay Protection

Protection setting is calculated offline in our country. With the change of electric power system operating state, protection setting should be changed in time. However, protection setting changing in large quantities will reduce reliability of relay protection and the safe and stable operation of electric power system. In order to avoid the disadvantages, setting adjustment should be done during setting calculation. Setting adjustment means judging applicability of the original setting under the new operating state and getting the conclusion whether protection need to change setting. Setting adjustment can induce the quantity of protection whose setting should be changed and avoid protection setting changing in large quantities. It is of important significance for electric power system to research on setting adjustment principle and to make the setting calculation software have the function of setting adjustment deeply.On the basis of stating the importance of setting adjustment, this article divides protection into two parts: protection without longitudinal matching relationship and protection with longitudinal matching relationship and researches on the setting adjustment principle and its realization algorithm separately. Practical examples show that the proposed algorithm is available and practical.The selectivity of protection should be detected during setting adjustment and calculating the coverage of protection according setting is an important step. In order to overcome the disadvantages of traditional ways, detecting measurement is introduced into coverage calculation and the method of calculating coverage of line protection on the basis of detection measurement is discussed. The method can speed up the selectivity detection. Practical examples show that the proposed algorithm is accurate.This article performs the overall design of setting calculation and develops the module of setting adjustment. The module has the function of setting adjustment, selectivity detection and coverage calculation. The interface of module and key technology are discussed.The realization of setting adjustment can avoid protecting changing in large quantities after the operation state of electric power system changes, cut the possibility of mismatch protection and misoperation, improve the reliability of relay protection and the safe and stable operation of electric power system, and enrich function of the setting calculation software for relay protection.