Wireless energy harvesting for rotor instrumentation in electrical machines

In order to perform experiments on electrical machines, it is desirable to measure rotor parameters such as currents and temperatures. A Bluetooth module have been developed which sends data from the rotor, however this module is battery powered, and therefore the duration of the tests is limited. This paper presents a solution to this problem, by developing a rotor-mounted power supply system which can harvest energy from leakage magnetic flux inside the machine, by fixing an external loop to the rotor and making use of induced voltages in the loop. A full-bridge rectifier, boost converter and battery charging module was developed to supply sufficient power to the Bluetooth module.