Yaskawa CIMR-V7AM-091 - Manual (Page 15)

Date: 02/20/05, Rev: 05-02 Page 15 of 15 TM.V7SW.091
2.6 Guidelines of Selection and Adjustment
Regenerative power required to continue operation.(Pm)
Pm (kW) ≧ Load Power (kW) ／ (Drive Efficiency×Motor Efficiency)
Required deceleration torque (Tm)
Tm (Nm) ≧（60×Pm）×10 3 ／[2π×Motor RPM]
Note: Tm must be within the range of motor (drive) stalling torque and overload capacity
Deceleration time (td)
td (sec) ≦ [2πx (Reflected Load Inertia + Motor Inertia)×(Motor RPM)／(60×Tm) ]
Note: In the above equation, Inertia is expressed in kgm 2
Undervoltage (UV1)Trip time at power loss with no KEB (tuv)
tuv (msec) = [Drive Capacity (kW)／Load Power (kW)]×15msec
Required backup capacitor capacity to be added for given backup time (Cb)
Cb (μF) ≧ [(2×P1×10 3 ×tb) ／(Vn 2 －Vf 2 )×0.9]×10 6
Note: In the above equation;
PI: Load power (kW)
tb: Backup time (sec)
Vn: Main circuit DC bus bar voltage (Vdc)
Vf: Undervoltage (UV1) trip voltage (Vdc)