The First Step of Servo Tuning using SERVO GUIDE发那科

INDEX

1.Introduction (3)

2.Initial Servo Parameters For High-Speed and High Precision Operations (7)

3.Gain Tuning by Tuning Navigater (9)

4.Tuning of Acceleration and Deceleration (11)

5.Tuning of Circle (12)

6.Tuning of Square (14)

7.Tuning of Arc Square (17)

1.Introduction

This manual explains the basic of servo tuning by using SERVO GUIDE. Please try to do servo tuning according to this manual. Then you will get easily good performance.

1.1.S ervo HRV Control

Servo HRV2 and HRV3 improves current loop performance and it leads higher performance of servo system. It is important to understand the rough structure of servo control and how to

realize high performance by using HRV2 and HRV3.Followings explain the basic of servo tuning procedure using SERVO GUIDE.

With the i series CNC (90B0 series), the employment of SERVO HRV2 and HRV3 control improves current loop response, and therefore enables the setting of a high and stable gain for the velocity loop and position loop.

With higher velocity loop and position loop gains, the response and rigidity of a servo system can be improved. This capability enables cutting figure error reduction and higher-speed positioning with machine tools. Moreover, this capability simplifies servo adjustment. Thus, SERVO HRV2 control can improve overall servo performance.

Achievements of SERVO HRV control

After the servo system is adjusted with SERVO HRV2 control, higher-speed current control can be achieved with SERVO HRV3 control, thus enabling even higher-level precision machining. When SERVO HRV control is combined with CNC advanced preview control, AI contour control, AI nano contour control, and high-precision contour control, much improved machining can be performed.

For details, see Subsec. 3.4.3, "Servo Parameter Adjustment Procedure for Achieving High-Speed and High Precision" in Parameter Manual ( B-65270 ).

Servo HRV1 control

Servo HRV2 control

Servo HRV3 control

(R100 mm, 10000 mm/min, without quadrant protrusion compensation)

Example of effects of SERVO HRV control

1.2.

Adjustment procedure outline

Use the procedure below for SERVO HRV2, 3 control setting.

SERVO HRV control adjustment

l Setting of a current loop period and current loop gain (*1)

The current control period is shortened from the conventional value 250 µs to 125 µs by setting HRV2 or HRV3. An improvement in current response serves as the base for performance improvement.

In order to select HRV2 or HRV3 control, please select Motor ID from 251 to 350 for αi s, αi s and βi s motors.

l Velocity loop gain setting (*3)

The use of the high-speed loop proportional high-speed processing function for processing a part of the velocity loop at high speed(No2017#7=1) is effective for a velocity loop gain adjustment.