Željko Despotović, Aleksandar Ribić, Mihajlo Pupin Institute, Belgrade, Serbia

15th INTERNATIONAL SYMPOSIUM on POWER ELECTRONICS - Ee 2009

NOVI SAD, REPUBLIC of SERBIA, October 28 - 30th, 2009

LOW FREQUENCY IGBT CONVERTER FOR CONTROL EXCITING FORCE OF

ELECTROMAGNETIC VIBRATORY CONVEYORS

VVIBRATORY CONVEYINGIBRATORY CONVEYING

Vibratory cVibratory cconveying process is conveying process is based on a sequential throw based on a sequential throw movement of particlesmovement of particles

The vibratory conveyors are widely The vibratory conveyors are widely used device in various technological used device in various technological processes for transporting and processes for transporting and finishing materialsfinishing materials

Vibrations of tank, i.e. of a Vibrations of tank, i.e. of a “load-“load-carrying element”carrying element” (LCE), in which (LCE), in which the material is placed, induces the the material is placed, induces the movement of material particles, so movement of material particles, so that they resemble to a highly that they resemble to a highly viscous liquid and the material viscous liquid and the material becomes easier for conveyingbecomes easier for conveying

VIBRATORY CONVEYING ALONG THE VIBRATORY CONVEYING ALONG THE HORIZONTAL SURFACE HORIZONTAL SURFACE

VIBRATORY CONVEYING ALONG THE SLOPED VIBRATORY CONVEYING ALONG THE SLOPED DOWN SURFACEDOWN SURFACE

VIBRATORY CONVEYING ALONG THE SPIRAL ELEVATORVIBRATORY CONVEYING ALONG THE SPIRAL ELEVATOR

VIBRATORY DOSING;CHARGING and (or) DISCHARGING VIBRATORY DOSING;CHARGING and (or) DISCHARGING

VVIBRATORY DRIVEIBRATORY DRIVE

MEMECCHANIHANICALCAL--with eccentrewith eccentre-centrifugal-centrifugallyly-iner-inertionaltional

ELEELECTRICALCTRICAL-rota-rotationaltional→→ electr. motionelectr. motion--linearlinear→→eleelectromagnetic drivectromagnetic drive

VIBRATORY DRIVE WITH VIBRATORY DRIVE WITH ECCENTREECCENTRE

CCENTRIFUGALLY VIBRATORY ENTRIFUGALLY VIBRATORY CONVEYING DRIVECONVEYING DRIVE

(a)- eccentric drive with one mass , (b)- eccentric drive with two masses

Electromagnetic Vibratory Electromagnetic Vibratory Conveyor with Fixing InductorConveyor with Fixing Inductor

Electromagnetic Vibratory Conveyor with Fixing Electromagnetic Vibratory Conveyor with Fixing Inductor and Directional Exciting ForceInductor and Directional Exciting Force

1-LCE

2-flexible elements

3-base

4-rubber pads

5-magnetic core

6-winding coil

7-armature

8-vibratory trough

9-inductive sensor

10-storage hopper

11-movable shutter

Analytical Model of Electromagnetic Analytical Model of Electromagnetic Vibratory ConveyorVibratory Conveyor

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Lagragian of system

Lagrange equation of motion

THE SIMPLIFICATION of ANALYTICAL MODEL

mb >> mk

Frequency Characteristics of Vibratory Conveying System(Vibratory Conveyor)

REALITY

EVA EVA like as a Generator of Forcelike as a Generator of Force

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(a)-mechanical model, (b)-magnetic circuit,(c)-equivalent electrical circuit

Electro Magnetic Force (EMF)

mechanical equation

electrical equation

static characteristic

Traditional Solution Controlling of Traditional Solution Controlling of Vibratory ConveyingVibratory Conveying

(a)-potentiometer

(b)-auto transformer

(c)-variable inductivity

(d)-magnetic amplifier

These ways of control are coarse and related to large energy losses, consequently this significant affect to rise of cost and increase dimension of regulation equipment

•The important overcome disadvantage of traditional ways of control is effectuated of development

semiconductor power converters

•Application of electromagnetic vibratory drive in combination with the power converters provides

flexibility during work

•Consequently, it is possible adjustment amplitude and (or) frequency of EVA coil current, i.e. adjustment intensity and frequency of exciting force applied on

conveying device, i.e. ADJUSTMENT AMPLITUDE and (or) FREQUENCU of MECHANICAL

OSCILLATIONS

Power Converters with Phase Angle Control (PAC)Power Converters with Phase Angle Control (PAC)

SCR power converters; (a)-unidirectional, (b)- bidirectional

AMPLITUDE FREQUENCY

Switching Switching PowerPower ConvertersConverters in in VibratoryVibratory ConveyingConveying

Controlling of Controlling of EVA EVA current current it is possible it is possible adjustment electromagnetic exciting forceadjustment electromagnetic exciting force applied applied on vibratory trough of conveyoron vibratory trough of conveyorFrom electrical standpoint, the From electrical standpoint, the EVAEVA is is mostly mostly inductiveinductive load by its nature, so that adjusting the load by its nature, so that adjusting the current of EVA is possible by:current of EVA is possible by:

--PWM voltage or current-mode control PWM voltage or current-mode control --ZVS or ZCS resonant controlZVS or ZCS resonant control

Triangle and sinusoidal half-wave of EVATriangle and sinusoidal half-wave of EVA current current

In this way it is provided amplitude In this way it is provided amplitude and (or)and (or)frequency frequency control of vibratory conveyingcontrol of vibratory conveying

Control of Sine Half-Wave Control of Sine Half-Wave of EVA of EVA CurrentCurrent

The waveform of electromagnetic driving force(a)-graphical harmonics representation, (b)-analytical representation

The Fourier spectrums at triangle drive current

(a)- driving (exciting) force(b)-displacement

Control of Triangle Half-Wave Control of Triangle Half-Wave of EVA of EVA CurrentCurrent

The waveform of electromagnetic driving force

(a)-graphical harmonics representation, (b)-analytical representation

The Fourier spectrums at

triangle drive current

(a)- driving (exciting) force(b)-displacement

Current-Mode Control in Vibratory Conveying-Current-Mode Control in Vibratory Conveying-generatinggenerating triangletriangle wave shape of EVA current wave shape of EVA current

Control circuit to provide adjusting triangle wave shape of EVA current;

(a)-principal scheme, (b)-characteristic waveforms

The influence reference value of peak current on the output displacement of LCE(a)-wave shape of output displacement and EVA current, (b)-detailed presentation of

interval I, (c)-detailed presentation of interval II

The Control Scheme of Resonant Electromagnetic Vibratory Conveyor

The Slides of The Slides of Implemented Implemented

PrototypePrototype

IMPLEMENTED PROTOTYPE of VCD

Mounting of acceleration sensor Mounting of displacement sensor

Electromagnetic Vibratory Actuator-EVA Vibratory trough-top view

IMPLEMENTED PROTOTYPE of POWER CONVERTER

Power Converter

PLL circuit

Acceleration Transmitter

EXPERIMENTAL RESULTSEXPERIMENTAL RESULTS

AMPLITUDE CONTROL

-sinusoidal drive EVA

-triangle drive EVA

(a)- VW=6mm(b)-VW=0.5mm

(a)- VW=6mm(b)-VW=0.5mm

Oscilloscopic Records of Characteristic Waveforms for VCD with Transistor Control

Voltage and current of EVA (a)- triangle drive (b)-sinusoidal drive

THE VIBRATORY DRIVE MOVIESTHE VIBRATORY DRIVE MOVIES

AMPLITUDE CONTROLAMPLITUDE CONTROL

FREFREQUENCY CONTROLQUENCY CONTROL

CURRENT 1A/cDISPLACEMENT 0,5mm/cTime 5 ms/c

AMPLITUDE CONTROL

FREQUENCY CONTROL

Time 5 ms/c CURRENT 1A/cDISPLACEMENT 0,5mm/c

AMPLITUDE –FREQUENCY CONTROL

PARTICLE TRAJECTORY

CONCLUSIONS CONCLUSIONS

•The most significant contribution of this research is The most significant contribution of this research is development optimal control of electromagnetic development optimal control of electromagnetic resonant vibratory conveyors and increase of theirs resonant vibratory conveyors and increase of theirs energy efficiencyenergy efficiency

•This is reached compensation of overall influences This is reached compensation of overall influences which relate to the violation of required resonant which relate to the violation of required resonant regime and changing resonant frequencyregime and changing resonant frequency

•The most dominated influences are:The most dominated influences are:-changing of conveying material mass-changing of conveying material mass-changing stiffness of flexible element-changing stiffness of flexible element-variation of mains voltage supply-variation of mains voltage supply

☺☺freedom to operate a VCD with any natural (resonant) frequency from 5 freedom to operate a VCD with any natural (resonant) frequency from 5 Hz to 150 Hz →frequency control Hz to 150 Hz →frequency control ☺☺the controller will continually search for the natural frequency of the the controller will continually search for the natural frequency of the vibratory conveyor (resonance) and excite it at that frequency (active vibratory conveyor (resonance) and excite it at that frequency (active tuning); in the located natural (resonant) frequency, it is possible to tune tuning); in the located natural (resonant) frequency, it is possible to tune amplitude and time duration of the EVA coil current i.e. amplitude amplitude and time duration of the EVA coil current i.e. amplitude oscillations of the LCE →amplitude control oscillations of the LCE →amplitude control ☺☺flexible automation with minimum change-over time because electronics flexible automation with minimum change-over time because electronics replace the comprehensive and the complicated calibrations and mechanical replace the comprehensive and the complicated calibrations and mechanical settingssettings☺☺many conveyors can be placed on the same electrical circuit without fear many conveyors can be placed on the same electrical circuit without fear of circuit overloadof circuit overload☺☺VCD can operate nondependent on mains frequency (50Hz-Europe or VCD can operate nondependent on mains frequency (50Hz-Europe or 60Hz-North America) without changing the conveyor springs or balancing 60Hz-North America) without changing the conveyor springs or balancing massesmasses☺☺energyenergy efficiency: efficiency:

minimum EVA coil currentminimum EVA coil currentminimum EVA coil heatingminimum EVA coil heatingminimum supply currentminimum supply currentminimum power consumptionminimum power consumption

HIGH PERFORMANCE OF VIBRATORY DRIVE

The idea for development proposed The idea for development proposed transistor switching converter is proceed transistor switching converter is proceed from lasting experience obtained on from lasting experience obtained on development and realisation SCR development and realisation SCR converters for drive vibratory conveyors in converters for drive vibratory conveyors in cement industrycement industry

At the ENDAt the END

THANK YOU IN THANK YOU IN ATTENTIONATTENTION!!!!!!!!