The Research On Discrete Sliding Mode Control Of Interleaved Magnetic-integrated Bidirectional

With the rapid development of technology, aerospace equipment, automotive equipment and appliances have been digitized, therefore their quality of power supply were required higher. The total output current ripple of multiphase inductor is lower than single DC/DC converter when multiphase interleaved technology was applied to traditional DC/DC topology. Therefore voltage ripple of load would be decreased with improved power quality. When magnetic-integrated technology was applied to the topology, faster inductor current dynamic response speed with various loads can be obtained. Analyze all the state of buck and boost working mode under full various duty cycle. Equations of inductor current and voltage ripple of each working mode had been got. A detailed analysis on the relationship between the phase-inductor current's ripple, the total four-phase-inductor current's ripple and voltage ripple with the magnetic coupling coefficient was given after numerical analysis. Aforementioned, optimal range of duty cycle and magnetic coupling coefficient can be defined. To improve the dynamic performance and robustness of bidirectional DC/DC converter system, adaptive discrete sliding mode control strategy was proposed, with reference voltage feedback controlling PWM. Establish the small signal modeling of the bi-directional DC/DC converter working on the Buck mode and Boost mode respectively with obtaining the system state space equation. Design the switching functions (sliding surface equation) and control law on the basis of equation aforementioned. ADSMC (adaptive sliding mode controller) were designed on the basis of the control purpose. Simulate the system under the two controlling strategy in the Saber environment. The strategy proposed has a lower sensitivity to load perturbation and parameter uncertainness. Also, higher dynamic response was got. Sampling system, data processing, algorithm controller and the DPWM controller were implemented on the FPGA for its rich resources and program running in parallel. A four-phase interleaved magnetics-integrated bidirectional DC/DC converter prototype was built to verify the theoretical analysis's correctness.