机车电传动 (Jul 2021)
Nonlinear Control Strategy of MMC-RPC Based on Lyapunov Function
Abstract
In order to comprehensively control the power quality in the traction power supply system, based on the power compensation vector diagram, the power relationship between the left and right power supply sections of the V/v traction transformer was analyzed. Taking the modular multi-level railway power regulator (MMC-RPC) as research object, the power quality problems such as negative sequence and harmonic in the traction power supply system were comprehensively solved by active power balance,reactive power compensation and harmonic power reverse injection. In order to improve the robustness of the internal and external disturbances during normal operation of the system, the MMC-RPC was controlled by the nonlinear control method of the Lyapunov function, and the basis of constant power and constant voltage was used in the outer loop. In the upper and inner loops, the nonlinear control strategy based on Lyapunov function was adopted. From the perspective of inner loop stability, the optimal control parameters were selected to ensure that the system could still operate stably and reliably when the line parameters on the power supply arm were perturbed or load switching. The MMC-RPC simulation system was built with Matlab/simulink to simulate the dynamic adjustment and anti-disturbance capability of the control system with the traction network load mutation and line parameter perturbation.Compared with the traditional double closed-loop PI control strategy, the control strategy is more feasible and effective.
