Modeling, Simulation, and Design of Electromagnetic Capacity Control System for Reciprocating Compressors

Designing an efficient and simplified electromagnetic capacity control system (ECCS) for reciprocating compressors, replacing hydraulic systems, is a crucial focus for energy conservation and efficiency enhancement in industrial production. Major challenges lie in the compressor's high gas force and rotational speed, coupled with the actuator coil's self-inductance, leading to complex response characteristics and capacity control failures under traditional on-off drive modes. To address these issues, this paper introduces a coupling control model for capacity control under synchronous frequency with asynchronous actuation of the actuator and suction valve, considering periodic excitation, reverse attraction, and partial stroke contact. By simulating actuator response and compressor performance under various voltage drives, as well as conducting a sensitivity analysis of various control parameters, we develop a load regulation procedure using Fixed Duration Timing Shift and Variable Duration (FDTSVD). This procedure achieves precise 0%-100% load regulation, with discharge volume relative error <7.5%. When the exhaust load decreases from 100 % to 25 %, the one-cycle indicated work decreases from 593.6 J to 175.2 J, demonstrating its effectiveness.