A technique facilitates a fracturing operation in a borehole and surrounding formation. The technique utilizes braking to arrest the rotation of an electric frac system and to thus limit the magnitude of a pressure peak in the event of an over-pressure shut down or other type of emergency shutdown. According to an embodiment, an electric motor is coupled with a fracturing pump which may be operated to pump a fracturing fluid into a well. Stopping or otherwise braking of the electric frac system is facilitated by applying rotor drag to a rotor of the electric motor.