MOTOR DRIVE DEVICE OF ELECTRIC FORKLIFT AND ELECTRIC FORKLIFT USING THE SAME

摘要

PROBLEM TO BE SOLVED: To suppress slipping of an electric forklift.SOLUTION: A torque command value generating part generates torque command values Tlref/Trref for commanding torque of first and second travel motors. Slip detectors 230 L, R, on the basis of speed detection values Vl/Vr and the torque command values Tlref/Trref, generates a slip rate estimation value representing slip state of a drive wheel. First and second slip detectors 230 L, R respectively include a first calculation part 232, and a second calculation part 234. The first calculation part 232 generates an inertia force estimation value *MtrAccTrq which is proportional to a differential value of the speed detection value Vl/Vr of corresponding travel motors. The second calculation part 234 generates a slip rate estimation valueαaccording to relationship of the torque command values Tlref/Trref of the travel motors corresponding to the inertia force estimation value *MtrAccTrq that corresponds.