EPE Association: EPE 1999 - Topic 06e: Applications

EPE 1999 - Topic 06e: Applications
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1999 - Conference > EPE 1999 - Topic 06: MOTION CONTROL AND ROBOTICS > EPE 1999 - Topic 06e: Applications

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   Comparison of Disturbance Suppression for Servo Drives
By S. Doenitz [View]
[Download]

Abstract: The accuracy of position controlled servo systems is dependent on the currently acting disturbance forces like friction forces, which act very closely at the load and machining forces, which include reactions from the machining process to the drives. This paper compares methods of estimation and compensation of acting disturbance forces with a position controller with additional integral-action component. All methods have been combined with common control structures like cascade and state control. Experimental results of a set-up with a disturbance force actuator underline the mode of operation.

   Damping of Torsional Vibrations in High-Dynamic-Drives
By T. Eutebach; J.M. Pacas [View]
[Download]

Abstract: The paper deals with the identification and damping of torsional oscillations in drives with large bandwith. The focus lies on a speed-controlled two-mass-system, which is realised in an experimental set-up by means of a field-oriented induction machine coupled with an external moment of inertia. On this plant, well-known procedures and damping methods will be compared regarding their effectiveness and effort of implementation. Besides the most important plant parameters shall be identified automatically and will be used for tuning of the system. The developed algorithms are implemented by using a fixed-point arithmetic.

   Fuzzy Auto-tuning for AC Speed Servo System with 2-Mass Load
By J. Yoshitsugu; K. Inoue; H. Ogiwara; M. Nakaoka [View]
[Download]

Abstract: In this paper, in order to suppress the mechanical resonance and anti-resonance in the DC brushless motor-based AC speed servo system with two-mass mechanical motion load, the load speed observer with load disturbance estimating function which is suitable for the load speed feedback compensation is proposed. And then, the gain parameters auto-tuning control implementation which is based on fuzzy reasoning with the observer-based load speed feedback compensation in addition to the conventional PI compensation using á-parameter ultimate sensitivity method[1],[2] is proposed and discussed from the experimental point of view.

   Improvement of Welding Performances Using Wire Feeding Speed Control
By J. S. Gho; Y. M. Chae; G. H. Choe; F. C. Lee [View]
[Download]

Abstract: In the gas metal arc welding(GMAW), the welding current is determined by wire feeding speed. Hence the constant wire feeding speed control is very important for arc stability. The fluctuation by external disturbances would deteriorate the welding performances such as more generated spatters and irregularly formed bead surface. However most wire feeder controllers have simple speed control loop of the phase control in the welding machines. To improve this, the four-quadrant chopper circuit is used for instantaneous speed and torque control. The proposed controller has two loops for speed and current control. The welding performances are compared with those of the conventional scheme, and hence the reduced spatter generation and better wire feeding speed can be obtained. This can verify the feasibility of the proposed scheme.

   Modelling and Analysis of a Loaded Bearingless Machine
By J. A. Santisteban; R. M. Stephan [View]
[Download]

Abstract: An electromagnetic and a mechanical model for a bearingless electric motor are presented. Based on these models, a controller structure is proposed and simulations presented. A laboratory prototype of this motor was constructed and experimental results with load validated the model. The proposed approach can also be used for the design of better controllers.

   Robust Control of a Nonlinear Two-Mass System
By I. Schöling; B. Orlik [View]
[Download]

Abstract: In this paper two robust position controls for an elastic coupled, nonlinear two-mass system are presented. One for the drive side, and a full state control for the load side. Using the „Exact Linearization“ as a basis, both control designs take the backlash into account. The state control is one part of the „Exact Linearization“. The choice of the eigenvalues is important here, because variations of parameters must also be considered. To reach steady state accuracy while disturbances occur in the system, the controls must be expanded. Therefore an additional „precontrol“ for the drive side control is designed. The full state control is expanded for the same reason by a PI-control. Both controls can handle oscillation, caused by elastic coupling, backlash and nonlinear friction. It is robust to variations of parameters. This includes large variations (400%) of the load moment of inertia. Some results are already tested on a test plant. More measurements to confirm the simulations are expected on the congress.

EPE 1999 - Topic 06e: Applications
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1999 - Conference > EPE 1999 - Topic 06: MOTION CONTROL AND ROBOTICS > EPE 1999 - Topic 06e: Applications
	[return to parent folder]

	Comparison of Disturbance Suppression for Servo Drives By S. Doenitz	[View] [Download]
Abstract: The accuracy of position controlled servo systems is dependent on the currently acting disturbance forces like friction forces, which act very closely at the load and machining forces, which include reactions from the machining process to the drives. This paper compares methods of estimation and compensation of acting disturbance forces with a position controller with additional integral-action component. All methods have been combined with common control structures like cascade and state control. Experimental results of a set-up with a disturbance force actuator underline the mode of operation.

	Damping of Torsional Vibrations in High-Dynamic-Drives By T. Eutebach; J.M. Pacas	[View] [Download]
Abstract: The paper deals with the identification and damping of torsional oscillations in drives with large bandwith. The focus lies on a speed-controlled two-mass-system, which is realised in an experimental set-up by means of a field-oriented induction machine coupled with an external moment of inertia. On this plant, well-known procedures and damping methods will be compared regarding their effectiveness and effort of implementation. Besides the most important plant parameters shall be identified automatically and will be used for tuning of the system. The developed algorithms are implemented by using a fixed-point arithmetic.

	Fuzzy Auto-tuning for AC Speed Servo System with 2-Mass Load By J. Yoshitsugu; K. Inoue; H. Ogiwara; M. Nakaoka	[View] [Download]
Abstract: In this paper, in order to suppress the mechanical resonance and anti-resonance in the DC brushless motor-based AC speed servo system with two-mass mechanical motion load, the load speed observer with load disturbance estimating function which is suitable for the load speed feedback compensation is proposed. And then, the gain parameters auto-tuning control implementation which is based on fuzzy reasoning with the observer-based load speed feedback compensation in addition to the conventional PI compensation using á-parameter ultimate sensitivity method[1],[2] is proposed and discussed from the experimental point of view.

	Improvement of Welding Performances Using Wire Feeding Speed Control By J. S. Gho; Y. M. Chae; G. H. Choe; F. C. Lee	[View] [Download]
Abstract: In the gas metal arc welding(GMAW), the welding current is determined by wire feeding speed. Hence the constant wire feeding speed control is very important for arc stability. The fluctuation by external disturbances would deteriorate the welding performances such as more generated spatters and irregularly formed bead surface. However most wire feeder controllers have simple speed control loop of the phase control in the welding machines. To improve this, the four-quadrant chopper circuit is used for instantaneous speed and torque control. The proposed controller has two loops for speed and current control. The welding performances are compared with those of the conventional scheme, and hence the reduced spatter generation and better wire feeding speed can be obtained. This can verify the feasibility of the proposed scheme.

	Modelling and Analysis of a Loaded Bearingless Machine By J. A. Santisteban; R. M. Stephan	[View] [Download]
Abstract: An electromagnetic and a mechanical model for a bearingless electric motor are presented. Based on these models, a controller structure is proposed and simulations presented. A laboratory prototype of this motor was constructed and experimental results with load validated the model. The proposed approach can also be used for the design of better controllers.

	Robust Control of a Nonlinear Two-Mass System By I. Schöling; B. Orlik	[View] [Download]
Abstract: In this paper two robust position controls for an elastic coupled, nonlinear two-mass system are presented. One for the drive side, and a full state control for the load side. Using the „Exact Linearization“ as a basis, both control designs take the backlash into account. The state control is one part of the „Exact Linearization“. The choice of the eigenvalues is important here, because variations of parameters must also be considered. To reach steady state accuracy while disturbances occur in the system, the controls must be expanded. Therefore an additional „precontrol“ for the drive side control is designed. The full state control is expanded for the same reason by a PI-control. Both controls can handle oscillation, caused by elastic coupling, backlash and nonlinear friction. It is robust to variations of parameters. This includes large variations (400%) of the load moment of inertia. Some results are already tested on a test plant. More measurements to confirm the simulations are expected on the congress.