Provided is a method and controller for controlling a vehicle dc bus voltage. The method includes generating a parameter. The parameter is based on a reference dc bus voltage squared, The method includes controlling the vehicle dc bus voltage based on the parameter and a detected dc bus voltage. The method may also include generating another parameter (S705) based on a power demand associated with at least one of a motoring mode operation and a generating mode operation of a. traction motor associated with the vehicle (S710). The power demand is indicated in a message received via a. dedicated high speed data bus. The method includes controlling the vehicle dc bus voltage based on the another parameter (S715).
