Research On Three-port Converter With Fast Dynamic Response For Pulse Load

The pulse load has become a kind of special load and be widely used in military and industrial fields,higher requirements are put forwarded for the pulse power converter.According to the pulse load characteristics,the paper researches the three-port converter with fast dynamic response performance for pulse load,the output current transient spike for the converter is greatly suppressed,which improve the stability of the output voltage,and then improve the performance of the dynamic response for the pulse power supply.The pulse-loaded three-port converter includes a forestage converter in parallel with a dual-inductance bidirectional Buck/Boost converter at the output port.Compared to traditional bidirectional Buck/Boost converter,dual-inductance bidirectional Buck/Boost converter has been improved on dynamic response performance from the aspect of topology optimization,the output current transient spike can be decreased by compensating the pulse current.But the dual-inductance bidirectional Buck/Boost converter with traditional dual control method still faces the problem of poor dynamic response performance: When the pulse frequency decreases or the energy storage capacitance value of the dual-inductance bidirectional Buck/Boost converter decreases,the voltage ripple of the energy storage capacitor increases,which resulting in the current inner loop tracking ability decreases,the output current transient spike is still present,which reduces the performance of the pulse-loaded three-port converter.Therefore,a hysteresis control strategy based on the output current of the forestage converter is proposed in this paper.By providing upper and lower thresholds for the output current,the generation of output current transient spikes is limited;The current loop is derived from the small signal model,and the mechanism of output current hysteresis control strategy to eliminate current spike is analyzed.Combined with valley voltage loop,the efficiency of dualinductance bidirectional Buck/Boost converter is improved.Finally,a peak power is 500 W,pulse frequency range is 100～500Hz,the pulse duty ratio is 0.2～0.8 of the experimental prototype is built,the output current hysteresis control is verified under different pulse load conditions,the results show that the proposed control method can effectively eliminate the output current transient spike,improve the stability of voltage at both ends of pulse load effectively.