基于STC系列单片机的车载逆变电源

Automotive inverter power supply based on STC

针对传统逆变电源启动困难的问题,对控制策略进行了改进,设计了一款以单片机STC12C5A60S2为主控芯片的两级式级联车载逆变电源。该电源以12 V直流电压为输入,通过升压与逆变两个功率变换环节得到了220 V,50 Hz的正弦交流电。在升压环节,采用直流母线电压负反馈,确保了直流母线电压的稳定性;在逆变环节,采用正弦脉宽调制(SPWM)技术,将输出电压的谐波畸变率(THD)降低到了5%以内。此外还对电池电压检测电路、输出电压检测电路、输出电流检测电路、桥臂短路保护电路进行了设计,并研制了实验样机。研究结果表明,采用逆变电路先触发升压电路后触发、根据输出电压实时更新占空比的控制策略,该逆变电源能够顺利启动,稳压特性良好,为以后逆变电源的优化设计提供了参考。

Aiming at the problem that inverter power supply in the past is hard to start,a two-stage automotive inverter power supply controlled by a single-chip microcomputer（SCM）called STC12C5A60S2 was designed by changing the control strategies.The input voltage is 12 V DC,through boost converter and invertion,the sinusoidal alternating voltage of 220 V,50 Hz was achieved.In the boost converter circuit,the DC bus voltage negative feedback was used to ensure the stability of the high voltage DC;in the invertion circuit,sine pulse width modulation（SPWM） technology was used,so the THD of output voltage is less than 5％.In addition,the battery voltage detection circuit,the output voltage detection circuit,the output current detection circuit,and the bridge arm short protection circuit were designed,and the hardware prototype was developed.The results indicate that the inverter power supply starts successfully and has a good regulation characteristic by using the control strategy that boost converter circuit triggered after invertion circuit and changing duty cycle based on output voltage.The results also provide the reference to optimal design of inverter power supply.