Research On AC Electrical Dynamometer System Based On LabVIEW

Recently, With the development in industry such as our country’s car, aviation and war industry as well as the stricter policy of environment protection, higher-level test technologies are required for the engine test. Aiming at the speed characteristics test, which is one of important test items of engine test, this paper ProPoses studies of AC electricaldynamometer and its control system.it regarded LabVIEW as the developing platform and adopted the wound-rotor induction machine as dynamometer, finally developed the system.First of all, regarded synchronous generator as the prototype, constructed dynamometer’s mathematical model through coordinate trandformation and Park equation.The armature reactor of electrical dynamometer is also explored in detail as it runs with pure resistive load. The elementary equation about electromagnetism torque is deduced, these steps have laid the base of the dynamometer system.Speed closed-loop control is a non-linearand real-time charter system, in this system fuzzy-PID control technology can be well work.So researched fuzzy-PID control technology in speed closed-loop control.As to the design of hardware of control system, designed the whole framework in the platform of testing. Taking computer as its core, the design methods and practical used circuit diagrams are presented to detect the torque, rotation speed, current, voltage, etc. And designed the control circuit of load resistance and excitation electric current control circuit.Adopted the load resistance is at control strategy "Adjust thickly ",The electric current of excitation is "Adjust thinly",and the self-adaptation fuzzy-PID control technology.it got up to the result, and improved systematic dependability and real-time character.The system regarded LabVIEW as the developing platform.This paper’s software mainly included data collection, data processing, data manager, interface design and output of control variables. It introduces synchronously a scheme that software covers for some typical magnifying, filtering wave in hardware circuit, which greatly simplify hardware and enhances the reliability and real-time charter of system.At last, the thesis did the experiment on the test bed. The result shows that:the control system of electrical dynamometer, which is based on Lab VIEW and Fuzzy-PID control, possesses satisfactory performance to meet the requirement of engine speed characteristies test.