| The construction of smart grid is the trend of current grid technology development.As an important node of power grid,substation is also developing into intelligence and information.Digital energy metering is the product of the development of intelligent substation,and the semi-digital energy metering system has been widely used.In order to ensure the accuracy of the measurement system,the State Grid Corporation attaches great importance to the detection technology of digital metering devices and has issued corresponding testing technical standards.At present,the semi-digital measurement system of intelligent substation is basically mature,but the development of detection technology of electric energy metering equipment cannot fully match the actual application requirements.The main performances are as follows: 1)The detection standard is only an isolated detection scheme for a single device,and there is no overall performance detection of the transformer,the merging unit,and the digital energy meter in practical applications;2)the current standard defaults to single-interval measurement,and actual digitization The substation is mostly cross-interval measurement,and the error caused by the inter-interval measurement mode is not reflected in the inspection standard;3)The detection environment is the laboratory environment,which cannot truly reflect the problem of the error of the digital energy measurement equipment under the actual complicated conditions.This paper refers to the existing testing specifications of digital energy metering,and proposes corresponding solutions to the above requirements: 1)designing the overall performance testing scheme;2)designing the multi-interval metering equipment testing scheme based on the inner bridge wiring;3)introducing the actual work in the testing process condition.In this paper,the solution is integrated and a digital integrated energy metering equipment simulation comprehensive detection platform is developed.The platform is divided into two parts: single interval and multiple interval.The single-interval part can perform the unit and overall detection of the merging unit and the digitized electric energy meter,and the multi-interval part is introduced into the actual working condition,and the multi-interval part introduced the actual working condition can perform the overall performance detection of the multi-interval metering transformer and the merging unit and the digitized electric energy meter.The multi-interval part is an emulation hardware platform using internal bridge wiring,and the programmable logic controller PLC and the supporting WINCC monitoring software realize the control of the working condition mode.Aiming at the real-time requirements of the simulation platform control operation,the scheme of avoiding the operational response delay caused by the WINCC software script queuing abnormality is studied.Finally,PLC’s Modbus communication polling time optimization and WINCC script type and data display optimization are adopted,and the phenomenon of script queuing abnormality is fundamentally solved by the combination of software and hardware.Finally,the functional test of the digital integrated energy metering equipment simulation comprehensive testing platform is carried out.The test results show that the platform can complete the overall performance test and can carry out research on the digital energy metering equipment detection technology. |
