The Development Of Regenerative Braking Energy Recycle Controller For Electric Forklift

Electric forklift is more and more universal because it is high energy conversion efficiency,no pollution, low noise, small vibration and so on. But the working time of a single charge isgreatly limited because of the existing battery technology and capacity. And frequent starting upand stop, so it is a great way to lengthen the working time by using its regenerative brakingenergy.According to the characteristics of high specific power, high specific energy density, shortcharge and discharge time, the super capacitor is used in regenerative braking energy recyclesystem, which could supply regenerative braking energy from the driving motor to the supercapacitor during the deceleration, barking or downhill. Realizing the energy recovery andprolonging the forklift working time. Excess regenerative braking energy is charged up the batterywhen the super capacitor is charged full of power. While starting or speeding up, the supercapacitor could provide short-term high-power energy to the load, avoid large current discharging,extending the using time of batteries.This paper first research on the overall plans of super capacitor used in electric forkliftregenerative braking energy recycle controller. First, decide the topology of super capacitorapplication, select Bi-directional DC/DC converter, carrying on the overall structural design andthe research of the control strategy according to the electric forklift working characteristic. Andthen design the hardware circuits and software of the device. Finally, fix the designed controllerand super capacitors to the KEF25electric forklift to test it, the data of the experiments areanalyzed and testified. The experiments indicate that the system could recover the regenerativeenergy effectively and efficiently, could make the batteries output current smoothly when forkliftstarting and accelerating. It has a good effect on the current reducing peak.