Synchronous Switch Energy Extraction Circuit for Motor Regenerative Braking Enhancement

The synchronous switch technique has been utilized as a promising solution to enhance the energy harvesting capabilities of piezoelectric devices. It utilizes a switched inductive branch to compensate for the capacitive source and increase the real power. The synchronous switch technique was also extended to enhance energy harvesting from electromagnetic (EM) sources. This brief introduces a synchronous switch energy extraction (SSEE) circuit and examinates its performance in motor regenerative braking (RB) enhancement. In the SSEE scheme, a switched capacitive branch is connected to compensate for the inductive source of an electromagnetic motor. The output current from a coil is made in phase with the induced voltage source. The braking power is significantly improved. Therefore, the kinetic energy is extracted much faster to brake the motor quickly, while a portion of the extracted energy is harvested into storable electrical dc energy. This brief comprehensively evaluates the SSEE performances, in terms of energy harvesting and motor braking, respectively. Experimental results show that, given a flywheel released from the same speed, the SSEE can recover 182.5% more energy than the diode-bridge rectifier. For the braking performance, the SSEE can reduce the braking time by 35.1%, compared with the short-circuit braking (SCB) case.