Modelling and Control of Electromagnetic Vibratory Actuator Applied in Vibratory Conveying Drives Željko V. Despotović, Aleksandar I.Ribić Department of Robotics Mihajlo Pupin Institute, University of Belgrade Belgrade, Serbia Volgina 15, Belgrade, zeljko.despotovic@pupin.rs Vladimir Šinik Technical Faculty “Mihajlo Pupin” University of Novi Sad Zrenjanin, Serbia Abstract—Modelling and amplitude/frequency control of one typical electromagnetic vibratory actuator are presented. Electromagnetic vibrating actuators are widely used as drives of vibratory conveyors and vibratory feeders. A resonant type vibratory drive is discussed. By suitable power converters and related PWM control one can achieve adjusting vibratory excitation force of vibratory actuator, i.e. vibratory conveying of particulate materials on conveyor load carrying element. Simulation model of the vibratory actuator has been generated by using program MATLAB. This model can be used as integral part of the simulation circuit (power converter and control circuit). The corresponding simulation and experimental results and their comparisons are presented. The experimental results are recorded by the practically implemented IGBT power converter and control system based on a PC104 module. Key words- Vibration control;actuator; power converter; IGBT; vibratory conveying; modelling; MATLAB; I. INTRODUCTION The vibratory conveyors and feeders having electromagnetic vibratory drives provide easy flow of particulate materials. Their application is widely used in various manufacturing industries (food, pharmaceutical, cement, etc). These vibrating machines are very popular because of their high efficiency and easy maintenance. This applies in particular to resonant vibratory conveying drives. However, their performance is highly sensitive to different kinds of disturbances. For example, as the conveyor (feeder) vibrations occur at its resonance frequency, vibration amplitude is highly dependent on damping factor. On the other hand, damping factor depends on the mass of material on the feeder through, type of material, and vibration amplitude [1]. These disturbances can reduce drastically (up to 10 times) the vibration amplitude, thus reducing the performance of the whole vibratory conveying drive. A key element that compensates these influences is the electromagnetic vibratory actuator (EVA) which is based on electromagnetic induction principle [2]. Also, vibration control of EVA is a very significant factor in resolving the aforementioned problem. The application of EVA in combination with power converter provides control flexibility. By providing operation of the vibratory conveying system in the region of the mechanical resonance, it behaves as the controllable mechanical oscillator [2-3]. In the present paper by combining IGBT power converter for driving EVA [4-6] with a feedback PI controller and state observer, a fast set point and disturbance rejection responses of the vibratory conveying drive are obtained. A high performance feedback controller is implemented on industrial PC platform and applied to the experimental conveyor. The simulations and experimental results confirm effectiveness of the proposed controller. II. DESCRIPTION OF VIBRATORY CONVEYING SYSTEM A typical arrangement of vibratory conveying system with EVA is shown in Fig.1. Its main components are the load carry element (LCE)-1, electromagnetic vibratory actuator (EVA) as source of excitation force F , and flexible elements- 2. Flexible elements (leaf springs) are made of a fiberglass composite material. These elements are rigidly connected to the base-3, which is resting on dumping rubber mounts-4 set on the foundation. EVA consists of magnetic core-5 covered by continuous windings coil-6. Electromagnetic driving force F acts on armature-7 rigidly attached to the LCE. This element carries the vibratory trough-8 along with particulate conveying material. The vibratory displacement is measured by a no- contact inductive sensor-9. Figure1. Typical construction of a vibratory conveying system having electromagnetic vibratory actuator. The previously described electromechanical system represents starting point for the creation of a mathematical model of EVA which drives LCE including particulate material. Since the mass of conveying material is variable, EVA will operate in regimes involving variable load, so it is necessary to make a correct stabilization of its operation [7-9]. III. MODELLING OF ELECTROMAGNETIC VIBRATORY ACTUATOR Fig.2 shows basic overview of the modelling vibrating system described in the previous section. The equivalent electromechanical model is shown in Fig.2 (a). This model consists of the electromagnetic and mechanical parts. The electromagnetic model of EVA is shown in Fig. 2(b). An This investigation has been carried out with the financial support of the Serbian Ministry of Education, Science and Technological Development - project No: TR33022.