Development Of The Monitoring Platform Of Hydraulic System Power Status Based On The Electric Signal Fusion Method

With the development of industrial automation, hydraulic equipment is more and more widely used due to its unique advantages. At the same time, hydraulic equipment is the mechanic-electronic-hydraulic integrated system, whose function is increasing and structure increasingly complex. The information and energy transfer process of the hydraulic system has become more complex. The system’s safety, reliability, energy-saving operation, and identification of the malfunction omen, are the hot issue which attracts the attention of scholars home and abroad. Asynchronous motor is the main power source of the hydraulic system, and its three-phase electrical signals contain the global information of the hydraulic equipment operation due to the effect of coupling of the rotor. By contrast, the pressure signals and vibration signals have the characteristics of low letter noise ratio and limited feature information due to the multi-coupling and strong coupling of the hydraulic system. Therefore, develop the condition monitoring and power optimization control technology based on the electrical parameters to solve the problem of high failure rate and inefficient. After the depth study of the hydraulic system state recognition technology based on the fusion of electrical parameters, an condition monitoring method, which is intuitive, online and graphical visual, is developed. The main contents are as follows:Firstly, the state monitoring method based on electric signals was studied, and Lissajous fusion method was found to make good use of the large number of system state information carried by the three-phase electric signals. With the fact that three-phase AC electric signals mixed with high-order harmonics, negative sequence components, the base band signals can reflect the operating conditions of motor and hydraulic system. So Hilbert transform and coordinate transformation methods are chosen to extract the base frequency component of the three-phase electric singles. The result shows that this extraction method ensured the speed and accuracy and meets the demand of online monitoring.Secondly, Lab VIEW software which is a graphical programming language is used to design the running status online monitoring platform of hydraulic system. Design the program for on-line monitoring and off-line analysis respectively to meet different requirements in practical application. The online monitoring system has realized the real-time acquisition and data processing of the motor’s three-phase electrical signals that achieve the purpose of the dynamic graphical visualization monitoring; The off-line analysis system original playback module, analysis module of the data, and the dynamic comparable module of the Lissajous fusion graphics which is needed in different condition;Calling for access to design the database management module by using the Lab VIEW database toolkit which is convenient for the user’s query, modify and call.Lastly, simulation of all kinds of working condition and texting the hydraulic system condition monitoring system based on electrical parameters in the hydraulic power system experiment platform which build for system diagnosing by multi-source information if analyzed. Through the contrast of the pressure and flow rate of signals, the text results show that the hydraulic system monitoring platform which we developed provides reliability and practicability which can provide technical support for the hydraulic equipment running status monitoring.