Slip control device for electric vehicle

A slip control device, provided in an electric automobile including a plurality of electric motor units individually driving a plurality of associated drive wheels including left and right drive wheels, for slip-controlling the electric automobile, the slip control device comprising:

• a threshold calculation module configured to calculate a normal angular acceleration of a first motor unit as a function of a manipulation amount of an accelerator to calculate a threshold for slip determination, on the basis of the calculated normal angular acceleration;
• an angular acceleration calculation module configured to calculate an angular acceleration of the first motor unit on the basis of a detection value from a rotation speed detection device that detects a rotation speed of the first motor unit;
• a slip determination module configured to determine whether a first drive wheel driven by the first motor unit has slipped, the slip determination module including:
• an angular acceleration comparison section configured to compare the angular acceleration calculated by the angular acceleration calculation module to the threshold to determine whether the angular acceleration exceeds the threshold or is equal to or higher than the threshold;
• a counting section configured to count a number of times the angular acceleration comparison section consecutively determines that the angular acceleration is equal to or higher than the threshold or exceeds the threshold;
• and
• a slip determination section configured to determine that a slippage has occurred, if the number of times counted by the counting section has reached a set value;
• and
• a torque limiting module configured to limit a torque developed by the first motor unit, if the slip determination module determines that the slippage has occurred, the torque limiting module including:
• an opposite drive wheel torque limiting section configured to limit a torque developed by a second motor unit that drives a second drive wheel laterally opposite to the first drive wheel determined as having slipped, as well as the torque developed by the first motor unit.