Elevator Energy Regenerative Unit (EERU) for energy saving in a Permanent Magnet Motor Elevator system

This paper presents an implementation of Grid connected Power Generation from Permanent Magnet Motor Elevator by Energy Regenerative Unit (ERU). The study reveals that permanent magnet motors with rated 7.4 kW in elevators which is working by transferring mechanical energy into electricity when the motor is rotating without power therefore the motor is capable of producing electrical energy back into the grid system. This situation is call “Regenerative mode” which is the wasted energy can be used once again [1]. The study is done by simulation using MATLAB/Simulink program and a construction of laboratory. The proposed ERU is used to convert DC voltage to AC voltage for gird synchronization. The ERU is operating as three-phase module. From experiment, it is observed that when the motor operates as a generator then ERU will receive DC voltage from DC BUS in the elevator inverter then convert to AC voltage that can be fed into the grid system. From the experiment, ERU can generate maximum power up to 5.5 kW of the rated of 7.4 kW Permanent Magnet Motor (PM motor).