Mitsubishi Electric MELSEC iQ-R RD75P4, Руководство пользователя

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7 CONTROL SUB FUNCTIONS
7.3 Function to Compensate Control
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7
Error compensation method
When the position control is performed using the movement amount per pulse set in the RD75 parameters, an error
sometimes occurs between the command movement amount (L) and actual movement amount (L').
That error is compensated in the RD75 by adjusting the values in [Pr.2] No. of pulses per rotation, [Pr.3] Movement amount
per rotation, and [Pr.4] Unit magnification (when [Pr.1] Unit setting is 0: mm).
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Definition
Error compensation amount used to perform the error compensation is defined as follows.
In the RD75, Movement amount per pulse is calculated with the following calculation formula. Movement amount per pulse is
A, [Pr.2] No. of pulses per rotation is Ap, [Pr.3] Movement amount per rotation is Al, and [Pr.4] Unit magnification is Am.
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Procedure
• Set Command movement amount (L) and perform the positioning. Set Movement amount per pulse (A) in advance.
(

Page 221 Movement amount per pulse)
• After the positioning is completed, measure Actual movement amount (L').
• Calculate Error compensation amount.
• Calculate the post-compensation [Pr.2] No. of pulses per rotation (Ap'), [Pr.3] Movement amount per rotation (Al'), and
[Pr.4] Unit magnification (Am') from Post-compensation movement amount per pulse (A').
(Adjust the values with Am' so that Al' and Ap' do not exceed the setting range.)
Error compensation amount
Actual movement amount (L')
Command movement amount (L)
=
= A × Am
Al
Ap
= Error compensation amount
L’
L
A’ A × Error compensation amount =
= × Am ×
Al
Ap
= × Am’
Al’
Ap’
L’
L
AL'
AP'
=
5×10
3
12000
×
101×10
3
100×10
3
=
5050
12000
=
101
240
[Condition]
[Positioning result]
[Compensation amount]
Movement amount per rotation: ..... 5000(μm/rev)
No. of pulses per rotation: .............. 12000(pulse/rev)
Unit magnification: .......................... 1
Command movement amount ........ 100mm
Actual movement amount............... 101mm
Movement amount per rotation: ..... 101(μm/rev) [Set in Pr.3 ]
No. of pulses per rotation: .............. 240(pulse/rev) [Set in Pr.2 ]
Unit magnification: .......................... 1
[Set in Pr.4 ]
Calculation example