Справочник Пользователя для Mitsubishi Electronics MDS-R

 
 
 

 

 

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If the position loop gain is increased or feed forward control (NC function) is used to shorten the 
settling time or increase the precision, the machine system may vibrate easily. 
SHG control changes the position loop to a high-gain by stably compensating the servo system 
position loop through a delay. This allows the settling time to be reduced and a high precision to be 
achieved. (SHG: Smooth High-Gain) 

(Feature 1)  When the SHG control is set, even if PGN1 is set to the same value as the conventional 

gain, the position loop gain will be doubled. 

(Feature 2)  The SHG control response is smoother than conventional position control during 

acceleration/deceleration, so the gain can be increased further with SHG control 
compared to the conventional position control. 

(Feature 3)  With SHG control, a high gain is achieved so a high precision can be obtained during 

contour control. 

 

The following drawing shows an example of the improvement in roundness 
characteristics with SHG control. 

 

-50.0 

0.0 

50.0 

 

<1> : Commanded path 

 

<2> : SHG control (PGN1=47) 

 
 

<3> : Conventional control (PGN1=33) 

 
 

Conventional 
control 

SHG control 

2.5 

m)

22.5 

method 

 
 
 
 
 
 
 
 
 

-50.0 

0.0 

 

50.0

 

During SHG control, PGN1, PGN2 and SHGC are set with the following ratio. 

 

   PGN1 : PGN2 : SHGC = 1 : 

8
3

 : 6 

During SHG control even if the PGN1 setting value is the same, the actual position loop gain will be 
higher, so the speed loop must have a sufficient response. If the speed loop response is low, 
vibration or overshooting could occur during acceleration/deceleration in the same manner as 
conventional control. If the speed loop gain has been lowered because machine resonance occurs, 
lower the position loop gain and adjust. 

SV003 
(SV049) 

PGN1 
(PGN1sp) 

Position loop gain 1 

1 

 23

 26

 33

 38

 47

1 to 200 

SV004 
(SV050) 

PGN2 
(PGN2sp) 

Position loop gain 2 

8 

3 

 62

 70

 86

102 125

0 to 999 

SV057 
(SV058) 

SHGC 
(SHGCsp) 

SHG control gain 

6 140 160 187 225 281

Always set a combination of 3 
parameters 

0 to 1200 

SV008  VIA 

Speed loop lead 
compensation 

Set 1900 as a standard for SHG control. 

1 to 9999 

SV015 FFC 

Acceleration 

rate 

feed forward gain 

Set 100 as a standard for SHG control. 

0 to 999 

 

 

 

The SHG control is an optional function. If the option is not set in the CNC, the 
alarm 37 (at power ON) or warning E4, Error Parameter No. 104 (2304 for M60S/
E60 Series NC) will be output.