A mixed H2/H∞ robust controller was designed to enhance the performances of Permanent Magnet Synchronous Motor (PMSM) control system. Firstly, the H∞ suboptimal controllers were designed with mixed sensitivity method. Then the controller with the best H2 performance standard was selected with Particle Swarm Optimization (PSO) and the H2/H∞ robust controller was obtained. Finally, the capability of mixed H2/H∞ controller was verified with simulation. The results indicate that the robust controller has better performance compared with traditional Proportional Integral (PI) controller, and the PSO algorithm is proved valid for the design of H2/H∞ controller in addition.

As one of the means to achieve calibration， the purpose of remote calibration is to determine the relationship between the measured value provided by the standard measuring instrument and the indicating value of the instrument to be calibrated through modern information technology， therefore the technology has important research significance for the digital transformation of calibration. Compared with traditional calibration， remote calibration has the advantages such as high calibration efficiency， low calibration cost， low dependence on calibration personnel， which is in line with the current development trend from traditional measurement to measurement in digital age. In order to further understand the use of modern information technology methods to achieve remote calibration， firstly， the current research progress of remote calibration technology was investigated and surveyed， the realization methods of remote calibration were summarized， that is， the methods with and without the standard measuring instrument in the field. Then， the example applications of the two types of realization methods were listed in terms of pressure， temperature， electrical energy， time and other calibration areas. Finally， the problems of remote calibration technology were summed up， and the future development trends toward digital measurement and smart measurement were put forward.