Design and investigation of high-speed, large-force and longlifetime electromagnetic actuators by finite element modelling

Electromagnetic (EM) solenoid actuators are widely used in many applications such as the automobile, aerospace, printing and food industries where repetitive, often high-speed linear or rotating motions are required. In some of these applications they are used as highspeed `switching' valves for switching pneumatic channels. This paper describes the finite element (FE) modelling and design of high-speed solenoid actuators. Operating at frequencies between 150–300 Hz, these actuators are unique in terms of the large force they produce (8–15 N) and the requirement for very long lifetime (2-5 billion cycles). The complex nature of electromagnetic, motional and thermal problems is discussed. The methodologies for FE modelling of such high-performance actuators are developed and discussed. These are used for modelling, design, performance evaluation and prediction of the above high-speed actuators. Modelling results showing some of the key design features of the actuators are presented in terms of force produced as a function of various design parameters.