基于国产嵌入式芯片的全数字控制轨道交通高压直流LLC电源研究

Research on Full Digital Control High-voltage Direct Current LLC Power Supply for Rail Transit Based on Domestic Embedded Chips

[目的]采用高效率LLC(电感、变压器、电容)拓扑结构的高压直流电源在轨道交通领域应用广泛。但由于LLC电路的变频控制特性,难以实现全数字化,且国产化研究滞后,故有必要开展相关研究。[方法]基于上海先楫半导体科技有限公司(以下简称“先楫”)HPM6300系列的全数字控制LLC高压电源电路,采用一次谐波近似法分析并建立电路模型;分析了电路系统程序的控制流程;通过搭建功率为1.5 kW的原理样机,进行试验验证。[结果及结论]证实了采用国产先楫嵌入式控制芯片HPM6300 MCU(微控制单元)来搭建LLC试验样机,并通过PFM(脉冲频率调制)+PWM(脉冲宽度调制)混合控制能够实现宽范围输入,能快速稳定电压输出,后续可采用不同的控制方式,在结构上进行改变,以实现宽范围输入。

[Objective]High-efficiency LLC(logic link control of)topology high-voltage direct current power supplies are widely used in the field of rail transit.However,due to the variable frequency control characteristics of LLC circuits,achieving full digitalization is challenging,and research on domestication lags behind.Thus it is necessary to carry out relevant research.[Method]Based on the HPM6300 series of full digital control LLC high-voltage power supply circuits from Shanghai Xianji Semiconductor Technology Co.,Ltd.(hereinafter referred to as′Xianji′),an analysis is conducted using the primary harmonic approximation method to establish a circuit model.The control flow of the circuit system program is analyzed.Experimental verification is performed by constructing a prototype with a power of 1.5 kW.[Result&Conclusion]The experimental results confirm that using the domestic Xianji embedded control chip HPM6300 MCU to build an LLC test prototype,and through PFM+PWM hybrid control,wide-range input can be achieved,and voltage output can be quickly stabilized.Different control methods can be adopted in the future,to achieve wide-range input with structural changes.