Stability Analysis of Power Fluctuation Suppression Converter in Pulse Load Power System

Abstract

The fluctuation of the input power of the radar system has affected the stability of the power supply system. The load in the phased array radar is a typical pulse load with a certain pulse width. The long pulse width, which is more than 2 milliseconds will make the input power fluctuate from zero to full load. The Power Fluctuation Suppression Converter (PFSC) is introduced and the nonlinear controller is proposed to reduce the fluctuation of the input power. The stability of the PFSC, which is a nonlinear system, is proved by the Lyapunov Theory. The system is global asymptotically stable under the nonlinear controller. The minimal controller gain is derived according the output voltage under the normal power. The filter parameter is determined by the minimal frequency and the magnitude of the fundamental wave of the input current is analyzed with the proposed filter parameter. The relationship between the energy storage capacitor and the peak-to-peak value of the output voltage is presented. The minimum and the empirical value of the capacitor are shown by the analytical expression. The Peak-Peak to Average Power Ratio (PPAPR) index is defined to measure the fluctuation of the input power and the approximation of PPAPR is derived analytically. The main results are verified by an example. The achievements lay an important foundation for the power supply system design with the long pulse width pulse load in the modern large scale phased array radar.