The subject matter of this specification can be embodied in, among other things, a method that includes receiving a first electrical current output setpoint, identifying a first operational condition based on the first electrical current output setpoint, providing, based on the identified first operational condition, a first pulse width modulated (PWM) signal having a first predetermined duty cycle, based on the first electrical current output setpoint, provided on a predetermined period, receiving a second electrical current output setpoint, identifying a second operational condition different from the first operational condition based on the second electrical current output setpoint, and providing, based on the identified second operational condition, a second PWM signal having a second predetermined duty cycle, based on the second electrical current output setpoint, provided on a predetermined multiple of the predetermined period.