Efficiency analysis of moving-magnet linear oscillating motor with dual-resonance for linear electro-hydrostatic actuator

More-electric aircraft draws considerable attention due to its high efficiency, high reliability, and easy maintenance. Linear electro-hydrostatic actuator is a novel linear actuation system suitable for more-electric aircraft, and offers many advantages over traditional rotary electro-hydrostatic actuator. However, it requires high-frequency reciprocate actuation of linear oscillating motors with both high efficiency and high power factor. In this study, a novel moving-magnet tubular linear oscillating motor with dual-resonance is proposed for linear electro-hydrostatic actuator applications to achieve high efficiency and high power factor simultaneously. Firstly, system impedance model is set up analytically, which helps to analyze the influence of structure parameters on system performance. Based on this model, working efficiency and power factor are compared with the nonresonance design, and validated by experimental results. In order to take real scenario into considerations, the nonlinearity of motor and rectangular-type load is also analytically derived and analyzed with effective resonant frequency tracking method proposed. It shows that dual-resonance design does increase system efficiency and power factor, and can be applied in linear electro-hydrostatic actuator system for more-electric aircraft effectively.