An electrified fire fighting vehicle includes a chassis, a tractive element coupled to the chassis, a pump having (a) an inlet configured to be fluidly coupled to a fluid source and (b) an outlet configured to be fluidly coupled to a fluid output, an electric motor configured to drive the pump to supply fluid received at the inlet from the fluid source to the fluid output, and a controller configured to control the electric motor to vary a speed of the electric motor to achieve a desired pressure of the fluid downstream of the pump while accommodating different inlet pressures of the fluid received at the inlet.

A method is provided for operating a drive train comprising an internal combustion engine or an electric machine as a primary drive and an electric machine as a secondary drive, wherein the electric machine is detachably coupled, together with an inverter and controller, on one of the vehicle axles. The electric machine and at least one switchable element is actuated in order to minimize drag losses of the electric machine and to provide a defined connection time for the electric machine. The electric machine is stationary and decoupled during a first speed range. The electric machine is actuated at a preset speed during a second speed range, where a defined connection time is not possible if the electric machine were stationary. The electric machine is coupled to the axle and rotates at the vehicle speed in the third range, when losses while coupled are lower than if uncoupled.

Provided is a control unit for an electrically driven vehicle, in which thermal effects on a control board and the like is reduced, and heat dissipation is satisfactorily A control unit (20) for an electrically driven performed. vehicle receives an operation signal and signals from various sensors, and outputs control signals for left and right inverters that drive left and right motors connected to left and right wheels, respectively. The control unit (20) includes, in a box (21), a first interface board (25) on which at least an interface with a large amount of heat generation is mounted, a second interface board (26) on which an interface with a smaller amount of heat generation than the interface mounted on the first interface board is mounted, and a control board (24) for generating a control signal. The first interface board (25) is disposed higher than the second interface board (26) and the control board (24) in the box (21).