Research On Self-Power Engine Vibration Fault Monitoring System

The engine condition monitoring method and fault diagnosis technique based on the basic characteristics of engine vibration signal is a significant mean of enhancing the operation reliability of the engine and reducing the blindness of the maintenance and repair work. In order to extract more complete and accurate operation information of the engine fault signal, a plenty of wireless acceleration nodes are usually employed and installed on the various positions of one engine. However, finding the non-battery power supply way for the wireless acceleration nodes is an inevitable and key issue to push the application of the engine condition monitoring method and fault diagnosis technique. This thesis proposes that using piezoelectric vibration energy harvester as sensor nodes "battery" scheme, especially research on the key technology of self-powered vibration monitoring node such as micro piezoelectric energy harvester, power management circuit, sensor driver, low power wireless sensor protocol. It makes a meaningful exploration for the mature use of the piezoelectric self-powered technology.Firstly, this paper analyzes the necessity and possibility of the application of vibration energy collection technology in engine condition detection and fault diagnosis system. Secondly, this thesis the ship engine vibration monitoring object, field survey the cylinder head vibration signal of "temples" type 6170 diesel engine in the upstream and downstream condition, and analyze the engine vibration stimulus source and vibration signal characteristics. And based on this, proposed using a piezoelectric vibration energy harvester as vibration monitoring node “no-battery” scheme. The analysis of the piezoelectric energy harvesting power management circuit technology, ultra-low power wireless sensor network technology, provide theoretical basis for the development of engine vibration monitoring system. According to the principle of "time exchange energy", The condition of intermittent power supply for accelerometer by the power management circuit, this thesis designed stability and reliability driver program for the sensor. This thesis transplant the applicable simpliciTI low-power wireless sensor network protocol, write the vibration monitoring node, relay node, control node software and PC client software, build a wireless sensor network from the node of vibration data acquisition to the PC display. Finally, manufacture the self-powered engine vibration monitoring system prototype, built a test platform of the self-powered vibration monitoring system based on the piezoelectric vibration energy harvester, complete the performance test and analysis of the prototype for self-powered engine vibration monitoring system. The test results show that the system can monitor the vibration signal of the engine stably, and can be analyzed and displayed by the software of the host computer.