Mitsubishi Electric MELSERVO-J3W Series, Инструкция по эксплуатации

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11. OPTIONS AND AUXILIARY EQUIPMENT
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(b) Losses of servo motor and servo amplifier in regenerative mode
The following table lists the efficiencies and other data of the servo motor and servo amplifier in the
regenerative mode.
Servo amplifier Inverse efficiency [ ] Capacitor charging [J]
MR-J3W-22B 70 17
MR-J3W-44B 85 22
MR-J3W-77B
MR-J3W-1010B
80 46
Inverse efficiency ( ) : Efficiency including some efficiencies of the servo motor and servo amplifier
when rated (regenerative) torque is generated at rated speed. Since the
efficiency varies with the speed and generated torque, allow for about 10 .
Capacitor charging (Ec) : Energy charged into the electrolytic capacitor in the servo amplifier.
Next, calculate the energy at different timings in one cycle of the operation. Energy is a positive value in
driving and a negative value in regenerative driving. Write down the energy during driving/regenerative
driving with signs in the calculation table as shown below. Negative values go into the shaded cells.
<Example>
Timing 1) 2) 3) 4) 5) 6) 7) 8) 9) 10)
A-axis E1 E2 E3 E4 E4 E5 E6 E7 E4 E4
B-axis E1 E2 E3 E4 E5 E6 E7 E5 E6 E3
Sum E 1) E 2) E 3) E 4) E 5) E 6) E 7) E 8) (Note) E 9) E 10)
Regenerative Es ES 3) ES 7) ES 10)
ER [J] ER ER ER
PR [W] ER/t
f
Note. Energy is not a negative value after summing regenerative driving driving
Calculate the sum of energy in each timing. For the timings (timing 3), 7) and 10) in the example) with
negative sum totals, calculate the next formula.
Subtract the capacitor charging from the result of multiplying the sum total of regenerative energies by
the inverse efficiency to calculate the energy consumed by the regenerative option.
ER [J] Es Ec
If the subtraction results are negative at all timings, the regenerative option is not needed. From the total
of ER's whose subtraction results are positive and a 1-cycle period, the power consumption of the
regenerative option can be calculated with the following expression. Regenerative option is not required
when the energy consumption is equal to or less than the built-in regenerative energy.
Power consumption PR [W] (total of positive ER's)/1-cycle operation period (t
f
)