碱金属热电转换器功率调节系统研究

针对碱金属热电转换器(AMTEC)的伏安特性,设计了DC/DC和DC/AC两级变换的功率调节系统.功率调节系统采用高频变压器隔离,避免了工频变压器产生的一系列问题.DC/DC变换器采用移相ZVS(零电压开关)PWM全桥变换和电压闭环控制,把AMTEC在较宽范围变动的输出电压变成稳定的直流电压.逆变器控制采用优化的特定消谐PWM技术,以滤波后总谐波含量(THD)为目标函数,计算预定开关角度.整个系统具有电压输入范围宽、转换效率高、输出波形THD低等优点.

Study on power conditioning system for alkali metal thermal to electric converter

The output voltage range of AMTEC is wide.This paper gives the design of a power conditioning system(PCS),which is composed of a DC/DC converter and a DC/AC converter according to volt-ampere characteristic of AMTEC.Two parts of the PCS is separated by high frequency transformer,so the disadvantage of low frequency one is eliminated.Using phase-shift ZVS full bridge and voltage closed loop control,DC/DC converter converts output voltage of AMTEC which fluctuates in a wide range to a steady voltage.The inverter uses optimal selective harmonic elimination PWM technology and computes predetermined switching angle,using total harmonic distortion factor as aim function.The experimental result shows that the PCS has the advantages of wide voltage input,high converting efficiency and low total harmonic distortion(THD) in output waveform.The power conditioning system proposed in this paper will be useful for the development of AMTEC with high power and high efficiency.