Electric drives¡ška.pdf · Load torque Dynamic torque Introduction, classification, load...

Projekt ESF CZ.1.07/2.2.00/28.0050Modernizace didaktických metod a inovace výuky technických předmětů.

Electric drives

Lecture 1 – Introduction, classification, loadcharacteristic

Ing. Jiří Kubín, Ph. D., Ing. Martin Diblík, Ph. D.

Modernizace didaktických metod a inovace výuky technických předmětů

2

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque

Introduction, classification, load characteristics

Course focus

• Obtain theoretical and practical know-ledges about basic parts of electric drives, their function and arrangement and typicalcharacteristics.



3

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Course lectures schedule1. Electric drive – definition, basic classification, mechanics of

el. drive, load characteristics of working machines, types ofmotion equations.

2. Mechanical characteristics of electric motors and workingmachines, operating modes, electromechanical transientprocess, run-up and follow-down time, working diagrams ofkinematics values

3. Sizing of electric drive, load types, methods of equivalentparameters, derating of drive due to working enviroment.

4. Basic principles and properties of el. machines, magneticcircuit, electromagnetic induction, force and torque in mg. field.

5. DC motor, principle, construction, commutation, armaturereaction, motor with separate, serial and parallel excitation

6. DC motor, speed control, braking, reversal, mathematicalmodel of DC motor with separate excitation


4

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Course lectures schedule7. Induction motor, principle, construction, voltage equations

and equvivalent circuit, energy balance and motor torque.8. Induction motor, operation states, startingm braking, speed

control. Math model, frame transformation.9. Induction motor, Math model, frame transformation.10. Synchronous motor, principle, construction, machine

torque, math. model.11. Synchronous motor with permanent magnets in rotor,

construction, properties, mathematical model.12. Electrically commutated DC motors, construction,

principles of control13. Special machines: Stepper motors (construction,

application, control methods), Reluctance motors andSwitching RM (principle, origin of reluctance torque)


5

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Course lectures schedule

14. Controlled rectifier, frequencyconverter, influence on supplymains and motor

15. Electric drive control unit. Blockdiagram, inputs/outputs,communication, safety functions


6

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


DefinitionMains

Switchingdevice

Converter

Motor

Mechanicaltransducer

Loadmechanism

Control

Indication

Operator

Superior control

Electric drive


7

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Advantages

• Wide power scale (10-3…108 W)• Wide torque/speed scale (10-3…106 Nm,

100…105 rpm)• No exhaust• Low acoustic noise• Easy to control and regulate• High efficiency• 4Q-operation• Easy operation and servicing


8

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Disadvantages

• Needs immediate power supply frommains.

• Low power/weight ratio (in comparison to hydraulic drives)

⇒ Wide use (everywhere)


9

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Sorting

• Rotational × Linear• Speed

– Single speed, double-speed– Step change, continuous change

• Motion continuous × discrete• Controllability (1Q, 2Q, 4Q)• DC, AC…


10

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Mechanics of electric drive

• Standstill (ω = 0)• Run-up• Run• Stopping (coasting × braking)• (reversation)


11

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Mechanics of electric drive• d’Alembert principle• Motion equation

Driving and load torques

Dynamic torque

Drive torque Load torque


12

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Mechanics of electric drive

• If J = const. then


13

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Drive torque

• Torque ch. M = f(ω)• Inverse torque ch. ω = f(M)

ω

M

synchronous

derivative

serial


14

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Load torque

• Active × passiveω

Mpassive

active

Active – mass lifting.Motoric

Motoric

Braking

Braking

I.QII.Q

III.Q IV.Q


15

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Passive load torque

• For description of common characteristicswe use equation:

∑=

+=n

1i

kiiL ω*b*sgnωaM

where a, bi, ki, n are constants


16

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Pz

Passive load torque

ω

M, P

Mz

Typical for planers and similar machine tools, cranetravels and continual mill lines

• Constant torque a=0, ki=0, bi = b0


17

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Passive load torque• Linear torque a=0, ki=1

ω

M, P

MzPz

It is typical for mechanims with viscous friction(rolling machines, calenders and most of textile machine


18

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Passive load torque• Quadratic torque a = 0, ki = 2

ω

M, P

Mz

Pz

Fans, compressors, blowers


19

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Passive load torque• Hyperbolic torque a=0, ki=-1

ω

M, P

Mz

Pz

Winders

Load torque


20

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Dynamic torque• Resistance of rotating solid against its

angular velocity change.

• J … moment of inertia [kg.m2]• Definition from mechanics

(solids‘element is accelerated by tangencial force):

Dynamic torque


21

Focus

LecturesSchedule

Definition

Advantages

Disadvantages

Sorting

Mechanics

Drive torque

Load torque

Dynamic torque


Dynamic torque• After integration:

All elements have same angular velocity.

• Inertia must be known for proper drive sizing• Calculation, measurement, documentation.

Dynamic torque


Tento materiál vznikl v rámci projektu ESF CZ.1.07/2.2.00/28.0050Modernizace didaktických metod a inovace výuky technických předmětů, který je spolufinancován Evropským sociálním fondem a státním rozpočtem ČR.

Thank you for yours attention

Introduction, classification, load characteristicsVložte název práce .. editujte v menu - záhlaví

Electric drives¡ška.pdf · Load torque Dynamic torque Introduction, classification, load...

Documents

Transcript of Electric drives¡ška.pdf · Load torque Dynamic torque Introduction, classification, load...