Papers by Author: Hui Zhang

Abstract: Specific to the parameters in the process of three-phase smart meter calibration, such as DC offset, AC offset, AC gain, etc. impact on measurement results, a design of a three-phase smart meter based on CS5463 chips is introduced in this paper. Through theoretical analysis, optimized calibration, and experimental verification, parameters such as voltage, current, active power, reactive power, apparent power, power factor can be measured by the meter. After calibrated, the voltage and current measurement accuracy of the three-phase smart meter can reach above 0.2%. It can meet the needs of the practical application.

Abstract: This paper develops a new separated mini-environment to provide a constant temperature chamber for the placement of Micro/Nano-metrology instrument. In this paper, the rule of temperature change with time under natural convection and coercive convection is presented. The measurement and control system is composed of TEC, programmable power source and precise temperature measurement system. The mathematic model of the constant temperature chamber is identified making use of system identification theory and system identification toolkit of MATLAB. The temperature stability is improved by applying auto-adaptive PID method. Experiments show that the temperature fluctuation of a single-point is less than 0.02°C and the whole field is within 0.05°C. The goal of high-precision temperature control is achieved.