# SINUSOIDAL STEADY-STATE POWER CALCULATIONS - PowerPoint PPT Presentation

1 / 31

SINUSOIDAL STEADY-STATE POWER CALCULATIONS. Prepared by: Ertuğrul Eriş Reference textbook: electric Circuits, Nilsson/Riedel. Updated: November 2011. INSTANTANEOUS POWER. Zero time: the instant the current passing through a positive maximum. This reference system requires

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

#### Presentation Transcript

Prepared by: Ertuğrul Eriş

Reference textbook: electric Circuits, Nilsson/Riedel

Updated: November 2011

Ertuğrul Eriş

### INSTANTANEOUS POWER

Zero time: the instant the current

passing through

a positive maximum.

This reference system requires

a negative phase shift of both

the voltage and current by θi.

Ertuğrul Eriş

Cos(ωt+Φ)

Cos ωt

Phase shift

+→Left

_ - →Right

Ertuğrul Eriş

Ertuğrul Eriş

### POWER

First term in instantaneus Power, average Power (Real Power),

constant, transformed to non electrical energy(light, heat) this energy is charged by the power companies

Second and third terms in instantaneus Power, frequency doubled, related average energy over a period is zero

Power factor (güç faktörü) = 0 max power

cos(φ), φ=θv-θi= π/2 power (0)

Ertuğrul Eriş

### POWER FOR PURELY RESISTIVE CIRCUITS

Amplitude, Vmİm=2 assumed

Ertuğrul Eriş

### «LAGGING POWER» FOR PURELY INDUCTIVE CIRCUITS

Reactive Power unit

VAR(Volt Amper Reactive)

Amplitude, Vmİm=2 assumed

Ertuğrul Eriş

### «LEADING POWER» FOR PURELY CONDUCTIVE CIRCUITS

Reactive Power unit

VAR(Volt Amper Reactive)

Amplitude, Vmİm=2 assumed

Genlik, Vmİm=2 düşünülmüştür

Ertuğrul Eriş

Ertuğrul Eriş

Ertuğrul Eriş

Ertuğrul Eriş

Ip=180mA

Ertuğrul Eriş

Ertuğrul Eriş

### EXAMPLE

P=8 kW

V=240 V rms

Pf=0.8

Complex S?

S=8+j6 KVA

Z= 5.76ej36.87=4.608+j3.456

Ertuğrul Eriş

### VARIOUS POWER CALCULATIONS

S= VeffI*eff= (1/2)VI*

Veff=Veffejθv

Ieff=Ieffejθi

Ertuğrul Eriş

### POWER CONSUMPTIONS FOR SOME HOME APPLIANCES

• Heater 1-2KW

• Owen1-2KW

• Refrigerator200-250W

• Washıng Machine600-1000W

• TV100-200W

• Vacuum cleaner500-1000W

• Dishwasher700-1000W

Ertuğrul Eriş

### ALTERNATE FORMS FOR COMPLEX POWER

S=ZIeffI*eff

P=|Ieff|2R=(1/2) im2 R

Q=|Ieff|2X=(1/2) im2 X

P= =|Veff|2/R

Q= =|Veff|2/X

Ertuğrul Eriş

### EXAMPLE-1: POWER COMPENSATION

precompensatıon

Vm=(R2+ω2L2)1/2 I1m

φ= φv- φi=atctg(ωL/R)

φ=530

cos φ=0,6

I1m =19,3 A

I1eff =13,7 A

Pave = 1876 Watt

Preactive=2409 VAR

aftercompensation

C=155μF

Vm=(R2+ω2L2)1/2 I1m

φ=00

Cos φ=cos( φv- φ ) =1; Sin φ=0

ZL= | ZL |e j φ= | ZL |= R / (1-ω2LC)2+ ω2R2C2=25.8

Resistive!

Im =12 AI1m =19,3 A

Ieff =8,53 AI1eff =13,7 A

Pave = 1876 Watt

Preactive=0 VAR

Ertuğrul Eriş

Ertuğrul Eriş

Ertuğrul Eriş

Ertuğrul Eriş

Ertuğrul Eriş

Ertuğrul Eriş

Ertuğrul Eriş

### EXAMPLE 3

a. What impedance should be connected across terminals a,b for a maximum power transfer

b. What is the maximum power transferred to the impedance in (a)?

c. Assume that the load is restricted to pure resistance. What size resistor connected across a,b will result in the maximum aserage power transfer?

d. What is the maximum power transferred to the resistor in (c)?

ig=3cos5000t A

a. 20-j10; b.18W; c. 22.36Ω; d.17W

Ertuğrul Eriş

EXAMPLE 4

İ2(rms)=840/140

Ertuğrul Eriş

PROGRAM DESIGN

DEPT, PROGRAM

G

R

A

D

U

A

T

E

S

T

U

D

E

N

T

STUDENT

P

R

OG

R

A

M

O

U

T

C

O

M

E

S

PROGRAM OUTCOMES

P

R

OG

R

A

M

O

U

T

C

O

M

E

S

STATE, ENTREPRENEUR

FIELD

QALIFICATIONS

EU/NATIONAL QUALIFICATIONS

KNOWLEDGE

SKILLS

COMPETENCES

NEWCOMERSTUDENT

ORIENTIATION

GOVERNANCE

Std.

questionnaire

ALUMNI, PARENTS

ORIENTIATION

STUDENT

PROFILE

Std.

questionnaire

FACULTY

NGO

STUDENT,

???

CIRCICULUM

???

INTRERNAL CONSTITUENT

Std.

questionnaire

EXTRERNAL CONSTITUENT

EXTRERNAL CONSTITUENT

REQUIREMENTS

EU/NATIONAL

FIELD QUALIFICATIONS

PROGRAM OUTCOMES

QUESTIONNAIRES

QUALITY IMP. TOOLS

GOAL: NATIONAL/INTERNATIONAL ACCREDITION

### BLOOM’S TAXONOMYANDERSON AND KRATHWOHL (2001)

!!Listening !!

Doesn’t exits in the original!!!

http://www.learningandteaching.info/learning/bloomtax.htm

Ertuğrul Eriş

ULUSAL LİSANS YETERLİLİKLER ÇERÇEVESİ

BLOOMS TAXONOMY

Ertuğrul Eriş

### COURSE ASSESMENT MATRIX

LEARNING OUTCOMES

Devre Analizi İlk Ders

Ertuğrul Eriş