Based On The Virtual Instrument Technology Inverter Monitoring System

Power electronic technology is a new technology emerged and developed in the last20th century. It is a new technology platform that composed by power semiconductor, modern control technology, computer technology and circuit technique. Along with the rapid development of power electronic technology, it starts to be widely applied in the operation of traditional equipment, new energy development, power quality control and civil product. However, the faults of power electronic devices is often fatal and unrecoverable and will cause the damage of the whole equipment, interrupt the production and bring the significant losses. In this case, guarantee of the security and liability of power electronic device means a lot to the entire system.This paper analyzed the relevant principle and working condition of inverter, which was a common power electronic device. And based on this, a inverter fault monitoring and diagnosing system was designed to monitor and anticipate the fault.After a full analysis of the demand, I designed this system based on virtual instrument technology. The data acquisition card NI USB-6009and the signal conditioning circuit was used to acquire voltage and current data, which composed the slave computer of this system. And the program developed by LabVIEW as the upper computer, was able to display the fault wave acquired by the slave computer in real-time and stored these data to do simple spectrum transform and sent them to the remote monitoring system, which perfectly met the excepted requirements.In the part of fault diagnose, this paper did spectral analysis to monitor the faults, and applied the wavelet packet signal decomposition/reconstruction and associated neural network theory to diagnose the fault signal and proved their practicality.