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Multi-break vacuum circuit breakers (VCBs) is an important research direction for scaling VCBs up to a higher voltage level. A VCB module with an integrated operation of double-break is designed to increase synchronization of multi-break VCBs, and the synchronization error beyond the mechanical structure is eliminated. First, the mathematical model and motion model of the transmission system were established. Then the motion characteristics and the double-break synchronization error of the module were analyzed. Finally, the prototype was designed and manufactured for parameter testing and trajectory verification. The analysis shows that the displacement transmission ratio increases with the increase in the transmission pull rod length and the initial closing angle. The length of the transmission pull rod has little effect on the displacement transmission ratio, while the initial closing angle has a major effect on it. The simulation results show that the transmission system can realize maximum control of the double-break mechanical error to within 0.59 mm with the IT12 level and the mechanical error obtained by the root sum squared method can be within 0.3 mm. The maximum mechanical error can be controlled to within 0.06 mm by improving the tolerance and fit of moving pairs to the IT6 level. The experimental results reveal that the maximum mechanical error of double-break’s clearance between open contacts is 0.49 mm and the synchronization error is not greater than ±0.1 ms. It is proved that the module can realize high precision synchronous operation. This study provides a practical design idea and processing requirements for the control of synchronous errors of multi-break VCBs.

Gypsum hollow block is an important new material, which has a broad development prospect and promising. It can not meet the market demands because the technical and other reasons of the domestic enterprises, which restrict the development of the gypsum hollow block production. Therefore, the development and design of the gypsum hollow block production equipment have great significance. In this paper, the control system of the gypsum hollow block production equipment is introduced. The motors in the system are controlled by PLC and inverter, which can make the system operate smoothly. The production process such as ferruling, core-pulling, casting and molding can be controlled automatically according to the signal of the sensors, which can improve the productivity and reduce the operating costs. The system is also equipped with remote monitoring to realize the soft control. Experiments show that this control system has high reliability and stability.