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针对传统的驱动电路固定化的驱动电流无法优化开关器件损耗的问题，提出了一种根据开关管电流调整器件关断速度的方法。在一个平均电流控制的Boost电路中，用电流指令信号来调节驱动电路的关断电流大小。当电流指令信号越大时，驱动电流的关断电流越小；反之相反。这样就实现了在小电流(轻载)下开关管的关断速度更快，关断损耗更小。可以使用一个晶体管电路来实现电流指令对驱动关断电流的调整。设计的原则是，在一定的小电流下器件的关断电压尖峰不大于额定电流下器件的关断电压尖峰。分析了器件的关断特性，讨论了尖峰电压与驱动电流和漏感之间的关系。在一个200 V输入/380 V输出/功率1 kW的Boost电路上进行测试，结果表明采用所提出的驱动电路，轻载下效率比传统的方法提升了1%以上。“,”The fixed-driving- current in the traditional driving circuit couldn’t optimize the power losses of power switches, therefore a new method for regulating turn-off speed based on switch current is presented. The turn-off current of the driving circuit is regulated by the reference current signal in a boost converter using average current control mode.With this control method, the larger the reference current signal is, the smaller the turn-off current will be, and conversely, it is opposite. Thus, the turn-off speed of power switches becomes more rapid and turn-off loss becomes lower under a small current (light load). A transistor circuit can be used to implement this function. However, all of this must be based on one principle that the turn-off spike voltage under a smaller current is not greater than the voltage spike under a rated current. Besides, the turn-off characteristics of power switches and the relationship among voltage spike, driving current and leakage inductance are discussed in this paper.Finally, a boost converter with 200 V input voltage, 380V output voltage, and 1kW output power is built to test the proposed method. The results showed that the converter efficiency using the proposed driving circuit under light load rises by 1% more than that in a traditional driving method.