Abstract <p>A circuitry diagram of a power switch unit intended for to provide an increase in power of special-shaped electrical signals powering the electromagnets of metering valves or injectors in the fuel injection systems of medium-speed diesel engines. The chosen control signal waveform consists of the following three stages: forcing, holding, and demagnetizing. The circuit provides an increase in the energy efficiency and reliability of the electromagnetic drive through reducing dissipated power in the course of magnetizing current formation and enhancing its operational stability. This can be achieved through the use of differentiator units in the circuit, which, in combination with other additional elements, restricts the forcing pulse at the moment when the electromagnet armature is attracted to the core. A computational simulation of the electromagnetic drive is performed, and the calculated relationships for the winding current, voltage, and the displacement of the electromagnetic gate are presented. The proposed method for restricting the forcing pulse duration and the circuitry solutions are applicable to any power switch assembly design since the reliability of the electromagnetic drive is increased not only through reducing power consumption, but also via eliminating the electromagnetic gate displacement sensor.</p>