Research On Wireless Telemetry System For Rotary Machine

A special data acquisition system is required during researching on the rotary machine, such as the aeroengine rotor. For the advantage of longevous, fitting for high rotate speed, the telemetry system for rotary machine was researched. Especially the wireless data communication and the contactless power transmission were researched. It includes:(1) The status and the disadvantages of traditional methods of the data acquisition system for rotary machine were summarized. And the wireless telemetry systems used now were expounded. Then a telemetry system for the rotary machine based on the wireless data communication and contactless power transmission was presented, and each part was introduced in detail.(2) A parallel wireless infrared data communication for the telemetry system was presented. And a parallel CODEC for this system was designed with CPLD. The miscarriage of justice begotten by the error of the electronic elements was resolved during the data communication with 4PPM at 4Mbps. And the data communication at 5.8Mbps was realized. Two methods of infrared data communication for rotary machines were presented. So the communication system can be set anywhere on the axis, and need not be set on its end. Then the parallel data communication structure was designed, and the data communication speed was increased by multiple.(3) The data communication system based on laser lamp-house was researched. The drive circuits for laser diode and amplify circuit for photoelectricity diode were designed. The SERDES was designed with FPGA, which can be used at 8.9Mbps. Then the dependability of data communication with an interstice between two fibers was tested. To solve the problem that it is hard to aim each other for fibers, the direct data communication between laser diode and photoelectricity diode is tried.(4) The data compression was studied to enhance the efficiency of the data communication. DPCM and DCT were used to compress the pressure and viberation parameters from aeroengine compressor. Then the two methods were combined, and the compress ratio was enhanced considerably. The error correction of coding was used to increase the dependability of the communication. BCH code was studied and designed with CPLD/FPGA. A decoding method was presented for BCH code which can correct one error bit. The inverse of BCH code generation matrix was used to shorten the time for decoding.(5) The contactless supply converter was applied for the telemetry system. A 10 watt power converter was designed based on the flyback switching power supply, and effects on the converter from the rotary status, gap between magnetic cores and eccentricity was analyzed through examinations.