大型电动轮矿用卡车电传动系统控制方案

Control scheme of electric driving system for large electric wheel mine-used truck

大型电动轮矿用卡车功率需求波动大,对加速时的后备功率和制动时的能量回收能力都有很高的要求,传统混合动力车辆采用的发电机组与单一动力电池并联供电的方式难以满足车辆对峰值功率和能量的双重需求。针对该问题,设计了大型电动轮矿用卡车电传动系统控制方案,并提出基于功率跟随与母线电压调节相结合的能量协同控制策略。在能量控制过程中,以发电机组和电池组作为主能量源跟随目标需求功率,以超级电容为辅助能量源,采用超级电容与发电机组交替工作的方式调节直流母线电压,使车辆能够根据行驶工况自动选择合适的母线电压调节方式。考虑电池最大充电能力及寿命的限制,提出了由超级电容负责电路能量回收并根据超级电容剩余电量情况缓慢向电池转移能量的方法。对特定车辆极端行驶工况的仿真结果表明,该控制方案保证了车辆具有充足的行驶动力,提高了电传动系统的效率;减少了锂电池的反复充放电次数,有利于延长锂电池的使用寿命;保证了大功率波动时直流母线电压的稳定,提高了电传动系统的可靠性。

The power demand of large electric-wheel mine-used trucks fluctuates greatly.It has high requirements for the backup power during acceleration and the energy recovery capacity during braking.The traditional hybrid vehicle adopts the parallel power supply method of a generator set and a single power battery.However,this method is difficult to meet the vehicle’s dual requirements for peak power and energy.In order to solve the above problem,a control scheme of electric driving system for large electric wheel mine-used truck is designed,and an energy cooperative control strategy based on the combination of power following and bus voltage regulation is proposed.In the energy control process,the generator set and battery set are used as the main energy source to follow the target demand power,the super capacitor is used as the auxiliary energy source,and the DC bus voltage is regulated by alternating the work of super capacitor and generator set.Hence,the truck can automatically select the suitable bus voltage regulation mode according to the driving conditions.Considering the limitation of the maximum charging capacity and the battery life,a method is proposed in which the super capacitor is responsible for the circuit energy recovery and slowly transfers energy to the battery according to the remaining power of the super capacitor.The simulation results of the extreme driving conditions of a specific truck show that the control scheme ensures that the truck has sufficient driving power and improves the efficiency of the electric driving system.The scheme reduces the number of repeated charging and discharging of the lithium battery,which is helpful to extend the lithium battery life.Moreover,the scheme ensures the stability of the DC bus voltage when the high power fluctuates,which improves the reliability of the electric driving system.