Study On Closed Loop Control System Of DC Dynomomter Based On DSP

Machinery indicatrix tests are important project in electric motor tests, so in the study, we focus on DC electrical dynamometer and their control system design. Based on the detailed analysis of dynamometer machine's operating principle, we made "measured electrical motor -- DC electrical dynamometer -- load resistance " as the objects for our study, analyzing the mathematic model of DC electrical dynamometer, the principle of system stability, exploring the analysis and choice of control strategy and the hardware, the software components of control system , and finally emboldening the control system for DC electrical dynamometer.Firstly, we focused on DC electrical dynamometer, analyzed the testing principle of torque and rotate speed, relationship among every main torques amounts when it runs, and also discussed the conditions for the steady operation of dynamometer system. Secondly, we deduced the time domain mathematic model for DC electrical dynamometer and done qualitative analysis for system's load control. It built bases for afterwards system simulates emulator models. Then, according to the test of system's unstable areas, a system control structure of the closed cycle couples back is confirmed and the control algorithms are carried out.For hardware design, we educed a series of design methods for signal detection and circuit disposal, and their specific schematic diagram, especially applicable for torque, rotate speed and current test. And we discussed the most important part of a control system, which are the function and principle of loads adjustment circuit and the excitation adjust circuit. While for software design, we developed and debugged the packets of control system by taking TMS320LF2407A DSP as platform.At last, our study successfully got the machinery indicatrix of the induction machine during system simulation and experiment. The results showed that, DC electrical dynamometer had a better control effect, which could satisfy the request that induction machine machinery indicatrix tests.