Apparatus and method for controlling an electric machine

A method of controlling an electric machine of a vehicle, comprising:

• receiving a torque communication signal indicative of torque communication through a belt associated with the electric machine;
• dynamically determining a torque limit for the electric machine in dependence on a magnitude of the torque communication signal with respect to a first torque threshold during operation of the electric machine, wherein the first torque threshold is indicative of a temperature threshold for the belt;
• and
• controlling the torque communicated through the belt associated with the electric machine in dependence on the torque limit,
• wherein determining the torque limit comprises:
• determining an integral of the torque communication signal with respect to the first torque threshold;
• and
• determining the torque limit in dependence on the integral of the torque communication signal.

A control system for an electric machine of a vehicle, the control system comprising one or more controllers, the control system comprising:

• an input arranged to receive a torque communication signal indicative of torque communication through a belt associated with the electric machine;
• one or more electronic processors arranged to:
• determine a torque limit for the electric machine in dependence on the torque communication signal and a first torque threshold,
• determine an integral of the torque communication signal with respect to the first torque threshold, and
• determine the torque limit in dependence on the integral of the torque communication signal;
• and
• an output arranged to output a torque limit signal in dependence on the torque limit to control the torque communicated through the belt associated with the electric machine.