Patent ID: 9543870
Date: 2017-01-10
CPC Classifications: B60L,Y02T

Claim:
1. A method of limiting motor torque in an electric vehicle, said electric vehicle comprising an electrical system, said electrical system comprising a battery pack coupled to a motor, said method comprising: measuring a battery pack current (i), wherein said battery pack current passes through a battery pack fuse; determining a characteristic of said electrical system, wherein said characteristic relates to a difference between said battery pack current and an operating limit of said battery pack fuse; determining a current limit based on said characteristic of said electrical system; determining a battery discharge current limit (I setting a maximum motor discharge power (MP setting a maximum motor charge power (MP calculating a motor efficiency (eff), wherein said motor efficiency is comprised of a plurality of power losses corresponding to motor losses and non-motor electrical system losses; and determining a first set of motor torque limits corresponding to positive rotor speeds and a second set of motor torque limits corresponding to negative rotor speeds, wherein said first and second sets of motor torque limits are based on said MP