A hybrid-electric powerplant (HEP) of an aircraft comprises a thermal engine providing a first torque input to the HEP and an electric motor providing a second torque input to the HEP. A power management system connected to one or both of the thermal engine and the electric motor comprises an engine control unit (ECU) connected to the thermal engine. The ECU controls fuel supplied to the thermal engine. An electric propulsion control (EPC) is connected to the electric motor and controls power supplied to the electric motor. The EPC includes an EPC protection module in communication with a power source for the electric motor. The EPC protection module disables power supplied to the electric motor upon receipt of a signal indicative of one or more of an over-speed condition and an over-torque condition detected in the HEP.