Research On The Technology Of Accuracy Improvement For The High-precision Dynamic Voltage And Current Standard

In a variety of laboratories which engaged in research work, an equipment that is able to output dynamic standard signal is quite useful. The standard signal can be used to conduct scientific experiments or calibrate equipments. There are various kinds of standard signal that are required, usually used to simulate the nature information. In response to these needs, this paper describes a high-precision dynamic voltage and current standard, which is able to output arbitrary waveform in limited bandwidth, and it’s static and dynamic signal are both very accurate.The high-precision dynamic voltage and current standard uses loop feedback structure to ensure high-precision. On this basis, conduct some research according to several factors that affect the accuracy of the system. The research mainly involves the following aspects.1) Noise analysis and noise reduction of the circuit system. Analyze the noise source and the noise magnitude of high-precision measurement circuit and high-precision output circuit, then reduce the noise from it’s source to improve the precision of the system. Experimental results show that the precision of the designed circuit system meet the desired objectives.2) Thermostatic control of the circuit system. Temperature is an important factor that affect the accuracy of precision instruments. This system realizes Thermostatic control of the circuit system based on thermoelectric cooler (TEC). Firstly, ensure the controllability of the heat and the temperature uniformity, then measure circuit temperature and realize system temperature constant by PID control.3) The design of control algorithm is very difficult to realize high-precision feedback control of the dynamic signal. This paper studies on two available algorithms, by comparing the effect of two control algorithms, selected a better one. The experiment show that whether static or dynamic output, the output signal are both very accurate. 4) The design of structure and man-machine interface of the system. The structural design of precision instruments should ensure reliability and electromagnetic compatibility, man-machine interface should be simple and elegant.Finally, design some corresponding test experiments in order to make sure that the precision of the instrument is good enough. By acquiring and processing experimental data, it is confirmed that the standard meets the desired accuracy.