Research On Dynamic Performance Optimization Control Technology Of DC Converter

DC converters are widely used in new energy power generation.For example,solar power generation requires the use of DC converters to convert solar energy into stable DC power.In addition,there are more and more electronic devices in daily life.As the heart of electronic devices,its output characteristics and dynamic response performance directly affect the core performance of electronic devices.For DC converters,on the one hand,due to their switching characteristics,power electronic systems constitute nonlinear systems with multiple inputs and multiple outputs(MIMO),and their inputs are constrained(for example,the duty cycle should be limited to 1).Over the years,many control strategies have been proposed,which are mainly based on traditional proportional-integral-derivative(PID)controllers combined with non-linear techniques such as pulse width modulation(PWM).However,because PID controllers are best suited for linear,single-input,single-output(SISO),unconstrained control problems,the design process of PID controllers for nonlinear MIMO systems with constraints becomes cumbersome.In addition,this type of controller usually achieves satisfactory performance only when adjusted within a very narrow operating range.Beyond this range,performance deteriorates significantly.Based on Boost converter,this paper mainly designs variable switching frequency control based on energy balance.Complete the energy analysis of the converter and calculate the energy of each part.The control parameters and constraint functions of the control strategy are designed.MATLAB is used to complete the simulation verification of the control strategy.The simulation comprehensively compares the start-up performance,dynamic performance,and robustness of variable switching frequency control and double closed-loop control based on energy balance to verify its feasibility and advantages.According to the structural disadvantages of the Boost converter,the two-switch Buck-Boost converter is used to complete the career conversion,which increases the degree of control freedom and reduces the difficulty of controlling the Boost converter.The cooperation of the two switching devices has been improved within a certain range.Dynamic performance of the converter.Finally,based on the energy balance,a universal constraint function was designed for the two-switch Buck-Boost converter,and the control of the two-switch Buck-Boost converter in any mode was realized.The simulation verification of the control strategy was completed in MATLAB.In this paper,a boost converter is used as a power stage circuit to build a hardware experimental platform.A variable switching frequency control experiment based on energy balance was performed on this hardware experimental platform.The dynamic response waveforms were analyzed and compared with the traditional double closed-loop control to verify its superiority.