Current Ripple Simulation in DC Traction Voltage System of an Electric Bus: 2

Abstract: Current ripple can cause a lot of problems as it spreads in the DC-side of the TVS of electric and electric hybrid vehicles. Fully knowing the properties of the TVS can be used to build a simulation model to determine the spreading of current ripple beforehand, which in turn is useful for calculating component placement, optimal filter sizes, and component lifetime. Being the second in line of an ongoing chain of thesis projects at Volvo buses, this master thesis proposes methods of measurement, simulation model adjustments, and usage of the finished model. Using an LCR meter, the impedance of several components was measured and modeled in LTSpice based on curve fitted parameters. Comparing the simulated properties to current and voltage levels measured in real vehicles, the accuracy of the models of different buses is presented and validated.