Based On Dsp Digital Signal Generator Development,

Signal generator is an important part in a control system. It is significant to design a digital signal generator with high-precision, reliability and adjustable parameters, which can promote the development in some fields, such as aviation, spaceflight, national defense and industry automation. The aim of this paper is to design a high-precision digital signal generator, which can produce three typical waveform signals to debug both the analog servo systems and the digital servo systems.According to the project requirements of the servo systems, the typical signals produced by the digital signal generator can be regarded as input signals to debug the system's performance. Besides, it improves the test signal of traditional analog servo system. By the digital-to-synchro converters (DSC), the typical signals can be converted to three-phase analogous voltage's output, which is synchro type and needed by the analog servo system. This overcomes some disadvantages in structure and electric performance of the mechanical-electronic sinusoidal signal generator. At the same time, the system especially designs a speed-feed-forward signal in order to reduce the static errors when the servo system tracks a high-speed signal.This digital signal generator adopts 16-bit DSP as its processor. By the software's method of timing and interrupting, it can produce three digital signals: step, constant speed and sinusoidal. These signals can be used to test static and dynamic servo system's performance and indexes. By setting accelerative time, starting and ending position, the constant speed signal can adapt servo system of different requirements. By the method of looking up table, the sinusoidal signal can produce little periodic signal, which is difficult for the previous signal generators. This digital signal generator provides excellent man-machine conversation interface. Operators can set the parameters of three typical waveform signals through the matrix keyboard and conveniently observe the input parameters from the LCD.In addition, the software of monitor testing on upper computer is designed and realized by the VC++ program language. By analyzing and disposing the output signal of the signal generator and the position angle signal of the servo system, the software of monitor testing can draw command curve, take-over curve and error curve. Through this we can observe real-time system's running-state and analyze the system's basic performances.The results of laboratory experiments and real system tests show that the digital signal generator has the advantages of simple structure, light weight and small volume, which can satisfy the demands of debugging servo system, and has a promising application prospect.