Overload Capability Optimization And Risk Assessment Method For Transformer

In order to improve the economy and security of transformeroperation, this paper has done a large amount of research focusing onhottest-spot temperature calculation method, overload risk assessment,parallel running mode optimization and intelligent evaluation systemimplementation for transformer.This paper analyzes the temperature distribution model of IEEEC57.91-1995and GB1094.7-2008, proposes an overload risk assessmentmethod for transformer based on hottest-spot temperature. The methodconsiders both transformer life loss risk and failure risk, applies failurerate theory and Weibull Hazard distribution and quantizes the economicloss caused by excessive high transformer hottest-spot temperature. Withthis method, simulation calculation of transformer risk for summer andwinter has been made under different types of load.Generally, only minimum power loss is considered when the parallelrunning transformer is in economic operation mode. Against this shortage,this article puts forward an improved constraint which takes into accountthe factor of transformer hottest-spot temperature in the same, combinedwith Two Typical Chronoisotherm Method, using binary search for theoptimal switching time point, to ensure both economy and safety forparallel running transformer.In this article, an assessment system with the implementation fortransformer overload capability optimization and based on IEC61850standard is presented. This paper designs a set of hardware platform andsoftware system which conform to the intelligent substation communication requirements, integrates the function of transformerhottest-spot temperature calculation, insulation life estimation, overloadcapacity assessment and risk prediction successfully. This systemprovides effective means to master and improve the transmission capacityof transformer.