Electric Wheel Dump Truck AC Drive System Based On Bond Graph Modeling And Control

AC drive system, as one of the core link in mine electric wheel dump truck, is a complex and nonlinear system with time-varying parameters, coupling and uncertain. The current model of the AC drive system is mainly modeled on a subsystem or in a control objective, with the development of dump truck's capacity, the structure of vehicle need to be improved and perfected to reduce the failure rate, short the maintenance time and enhance the practicability and reliability of vehicle, so the unity modeling of the whole AC drive system by using bond graph is undoubtedly necessary; power supply capacity of truck provided by on-board high-power diesel generator is limited, poor operating conditions and wide load fluctuation demand more of system's stability and robustness, and for the later whose analysis is also indispensable. Focusing on such two aspects, this paper studies the modeling of drive system by using bond graph and control in output voltage of the inverter; and its analysis of robustness in adopting vector control by bond graph to generator. The main contents of this paper are as follows:The modeling of power converter in AC drive system (including rectifier and inverter) and motor by bond graph, and verification of converter and motor in MATLAB and 20-sim. The Schottky diode in rectifier and inverter's IGBT is presented by element R and switch respectively in bond graph, equations of induction motor through coordinate transformation are compared to transformation matrix, and eventually motor's bond graph model is obtain in d-q coordinate. Parasitic resistance is introduced for elimination of algebraic loop caused by the causal conflict in inverter.Three phase inverter and LC filter are modeled by the bond graph where the mathematical control model is derived. Part of the LC filter is equivalent to the voltage source, and control the voltage of the capacitor in LC filter, the reverse bond graph model is established by introducing bi-way bond graph. View three-phase LC as voltage source, and LR load, design a resonant controller, and illustrate system stability by basically unchanged position of pole and zero during fluctuations in load, meeting its the end of robustness in complex operations; AC drive system's model is built through the element library based bond graph in MATLAB/Simulink, and vector control is adopted in frequency conversion and speed governing to motor.