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In this paper, a novel magnetization state (MS) control method is proposed by utilizing torque deviation to achieve the MS closed-loop control for variable flux memory machine. Firstly, the relationship between the MSs and the demand magnetizing current pulses is built into a look-up table, which also contains information on the flux linkages and the dq-axis inductances under different MSs. Afterwards, a model-based torque calculation is adopted for torque estimation, and then, the torque deviation between the present MS and the target MS can be obtained and utilized to generate the MS switch signal, which will determine the type of MS manipulation. Subsequently, the calculated torque will also be used for real-time monitoring of MS. The feasibility of the proposed MS control method is verified by simulation. Finally, experiments are carried out on a hybrid magnet memory machine control system for validation.

The switching-table-based direct torque control (ST-DTC) has the merits of simple structure, easy implementation, and fast response, but suffers from large torque ripples. Previous literature, i.e., the classical DTC, can achieve torque ripple reduction in the high-speed region but has a limited capability for torque ripple reduction in the low-speed region. In this paper, the issue of torque ripple reduction in the full-speed region, i.e., both the low-speed and high-speed regions, is addressed. The effects of each group in all possible six groups of virtual voltage vectors (VVs) on torque variation are firstly investigated. Then, a multiple VV DTC based on only three groups of VVs is proposed and the corresponding optimal selections of three VV groups and level of torque regulator are presented. The proposed DTC not only can effectively reduce torque ripples in the full speed region, but also is simple and easy to implement. The superiority of the proposed DTC with optimal selections of VVs and level of torque regulator are verified by experimental results.

On the basis of Eu(III)-4,7-bis(chlorosulfophenyl)-1,10-phenanthroline-2,9-di-carboxylic acid chelate (BCPDA) that was synthesized and characterized for time-resolved fluoroimmunoassay (TRFIA), Donkey anti-hepatitis B surface (anti-HBs) was labeled with BCPDA-Eu3+. Coomassie Brilliant Blue was used to determine the protein concentration and radio immunoassay (RIA) for detecting the biological activity in the labeled protein. Optimal conditions for the protein labeling were obtained by monitoring the reaction. Results suggested that the protein could be labeled with BCPDA under relatively moderate conditions. As a practical application, a protein-BCPDA-Eu3+chelate was obtained by using BCPDA-protein that reacted with EuCl3under certain conditions. Some properties of BCPDA and protein-BCPDA-Eu3+, such as absorption spectrum, emission spectrum and fluorescence lifetime, were discussed. The detection limit and the linear working range of the established method were also investigated.

The main purpose of curriculum ideological and political teaching is to form synergy effect of curriculum system. With the main channel of classroom teaching, ideological and political theory courses and other courses are taught together. Based on the related literature research and research, this paper analyzes the nature and characteristics of industrial design. The course combines the relevant contents of the ideological and political theory course and product design research, so as to strengthen the value orientation and correct guidance of students in the teaching of professional courses.