Download Power Electronics: Applications in Motor Control and Modern Lighting - Prof. George J. Col and more Study notes Electrical and Electronics Engineering in PDF only on Docsity! 1 LECTURE 2 Two Major Uses of Power Electronics: Motor Control and Modern Lighting I. Overview of Applications A. Overview B. Improved Motor Control C. Efficient Excitation of Gas Discharge 2 TWO MAJOR APPLICATIONS OF POWER ELECTRONICS: INDUSTRIAL ELECTRONICS A. Overview POWER ELECTRONICS USES NEW SWITCHING CIRCUIT TOPOLOGIES TO MAKE SMALLER, LOWER WEIGHT AND HIGHER EFFICIENCY POWER SUPPLIES. These supplies for the first time are available at variable frequencies need for applications in motor drive and in lighting which together constitute over 75% of electricity use. Clearly, we have different applications that place specific requirements on the solid state switches. Only as advances in solid state switches occurred could these new applications become cost effective. Switch technology is an enabling one for new applications. Two issues are enabling: electrical peformance and cost. B. Improved Motor Control 5 Below we will outline three pages of motor applications of power electronics in schematic form to allow an overview of the revolution taking place. We do so to motivate the study of power electronics by showing the rich applications that are emerging. Keep in mind in motor applications we need not exceed 20 or 30 thousand RPM and our power levels are up to MW. In general, output frequencies will usually not exceed 1-2 thousand RPM. Motor Drives
= A Motor Powered by an Electrical Drive
Converts Electrical Energy into Variable
Speed Mechanical Motion
Ba
Typical Industrial Applications
LOAD
a
mFans (~30% of market)
= Pumps (~20% of market)
a Conveyors (~20% of market)
m= Compressors (~3% of market)
= Cranes
mw Hoists
m Calendar Rollers
ma Winders
mExtruders
Motor Drive Markets
= Commercial
> Building Heating, Ventilating, & AIC
» Wastewater Treatment
> Non-Industrial OEM
mu Consumer
> Heating & AIC
> Major Appliances
> Computers, VCR’s, etc.
u Industrial
> Manufacturing Machinery
>Material Handling
> Fans and Pumps
Widely Used Motor Drives
m Low Power (< 250 Watts, < 100 Volts)
~Voltage Source PWM
~ DG Motors, Stepper Motors, PM AC Motors
m Medium Power (0.25. sao KW, 230 - 575 Volts)
~3-Phase Voltage Source PWM
>» Phase-Controlled Rectifier
~H-Bridge PWM
m High Power (> 1,000 kW, > 2,000 Volts)
>Current Source PWM
~Load Commutated Current Source
» Multilevel Voltage Source PWM
. »6-Phase, 12-Phase, etc.
Widely Used Low Power Drives
m One Transistor Voltage Source PMW
»DC Motors, Split-Phase PM AC Motors
BC+
co. BE) materwning
« Two Transistor Voltage Source PWM
> Stepper Motors (also switched refuctance)
ocr 2D Motor Winding
Each Motor Winding
Requires a Separate Circuit
Widely Used Medium Power Drives
m Phase Controlled Rectifiers
~DC Motors, Rectifier for AC Drives
« H-Bridge
>DC Motors
10
LAMP
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CAPACITANCE | ~~~ GROUND PLANE
©
BALLAST
* HF lighting electronics is here, and a lot more is
around the corner
* Most activities:
— in low-cost fluorescent applications (CFL and linear)
~ high-frequency HID
— automobile
* Frontiers:
~ electrodless
— backlights
Ballast Circuits
* Low-frequency * High-frequency
~ Lag — Parallel resonant
~ Lead — Series resonant
— Lead peak * Other
~ Switched DC ~ Power factor correction
— Starting circuits
A a= oz
AUP
TW .
Voclieel =e Viocsin(or
1
® ,.=—__—
Lm Ct
oc
_ 1
DooF
© fim (rca)
IogclW2)=/W 5 C2 Voplwe)
vhere:
Lm: Magnetizing inductance of transformer T1
Q1,02: Switched at resonance
N: Turns ratio of transformer T1 is assumed to be 1
L1>>bLm
PARALLEL RESONANT BALLASTS
02
fo
aca kh
aa
% fmt to
vi I
'p
a4 pl 4
oa Vos |i) Vy T
tam C1
| ik
LAMP
Yos
Vi twr) 22 Ving Sintwe)
V (wr)
1 (wt)=—* if 1
7 i
° jolt itci
2y2
L
/(wt)=—+-_V_sin(wr)
oO jawl?
vhere devices Q1 and G2 are switched at resonance.
SERIES RESONANT BALLASTS
