New Concept for Current-Impressed WPT to Multiple Independent Stainless-Steel-Enclosed Linear Actuator Sliders

Linear actuators (LAs) in pharmaceutical or chem-ical industries must be encapsulated into stainless steel (SS) enclosures to comply with extreme purity standards and facilitate thorough cleaning and disinfection. Therefore, advantageously wireless power transfer (WPT) should be used to supply the sliding part of such actuators, with the primary winding extended to cover the entire LA stroke, such that hard-to-clean cable car-rier assemblies can be eliminated. Typically multiple independent sliders and/or tool carriages must then be supplied from the same primary winding, resulting in a multi-receiver WPT system. However, providing power with a voltage-impressed method to such a system is challenging due to the voltage sharing among the receivers. Therefore, this paper proposes a novel current-impressed method suitable for multi-receiver WPT systems. The proposed method is thoroughly analyzed, optimized, verified by circuit simulations, and compared against a conventional current-impressed approach. As a result, the proposed method facilitates overload capability and has higher efficiency. The exemplary system is designed for two 100 W tool carriages and 72 V DC input and output voltages.