Analysis of the Power Quality of Multiple Directed Energy Loads on

an Electric Ship Power System

Keith Cohn & William ColsonNaval Postgraduate School

Robert Hebner & Angelo GattozziThe University of Texas at Austin

Picture from BoeingJune 17, 2010

Outline

• Overall Objectives• Motivation for Electric Ships & Integrated

Power Systems• Overview of Free Electron Lasers• States of Readiness for the FEL• Simulink Model of the FEL (and Combined

Systems)• Results

Objectives

• Determine the needed infrastructure and supporting equipment for the expected loads (FEL, rail gun, SONAR, radar, propulsion, etc.)

• Anticipate the possible time-dependent power profiles based upon expected operational scenarios

• Study transient effects on the power system• Provide a basis for a real time simulator for

personnel training

Integrated Power Systems• Conventional, segregated power systems isolate the majority of

power production for propulsion• Integrated power systems (IPS) provide a common power grid for

all loads, including propulsion

Segregated

Integrated

Components Modeled

• Free Electron Laser (FEL)• AN/SQQ-90 Sonar System• Electromagnetic Rail Gun• Active Denial System• Advanced Radar• Electromagnetic Aircraft Launch System• Laser Weapon System• Propulsion• Hotel Loads

Our computational model incorporates the following systems, all powered by an IPS:

What is an FEL?• No physical medium to damage • Natural scaling to very high average power• No harmful chemicals or exhaust• Technology can be designed for a wide range of wavelengths• Excellent optical mode quality• Good “wall-plug” efficiency (using an energy recovery linac)

Collaboration with NAVSEA, UTA-CEM, Stanford, AES, JLab

FEL Component Overview(maximum power draw)

FEL States of Readiness

Pier SideFEL in minimal power state; necessary

maintenance performed (425 kW) [days to reach from room temp]

UnderwayShip is crossing open waters; no imminent

threat (625 kW) [several hours to reach] [~50 gallons of fuel per hour]

Hot Standby Ship is in combat theater; threat could appear at any time (1 MW) [minutes to reach] [~80 GPH]

Engagement FEL is firing upon incoming threat (17 MW)[<1 s to reach] [~2.5 gallon per engagement]

Operational Readiness Between Shots

FEL is between consecutive shots (17 MW)[milliseconds to reach]

[~4000 GPH for normal cruise operations, excluding FEL]

Pierside

Underway

Hot Standby

Engagement

Operational Readiness Between Shots

6,000 V dc Bus

45,000 V dc Bus

450 V ac Bus

113 V ac Bus

4,160 V ac Bus

High Fidelity Simulation of the FEL Power Management on a Ship

Pier Side On/Off

Under Way On/Off

Turbine On/Off

RF Power On/Off

Beam Dump On/Off

Hot Stand By On/Off

FIRE On/Off

RESET On/Off

500,000 Vdc

Discrete,Ts = 2e-006 s.

v+-

v+-

v+-

v+-

v+-

v+-

v+-

v+-

v+-

Heat

RPM1

RPM2

RPM3

A

B

C

Neutral

Vacuum Pumps450 V, 60 Hz

com

A

B

C

a

b

c

Vacuum Pumps

A

B

C

+

-

Under Way

15000

Turbine RPM

A

B

C

a

b

c

Transformer4500/400000 V

500 Hz

A

B

C

a

b

c

Three-PhaseTransformer

4,160 / 450 V 60 Hz

A

B

C

a

b

c

n2

A B C

A B C A B C

A B C

In1Out1

In1Out1

In1Out1

In1Out1

In1

In2

Out1

In1Out1

In1Out1

In1Out1

In1

In2

Out1

In1Out1

In1Out1

In1Out1

In1Out1

Scope 9

Scope 8

Scope 7

Scope 6

Scope 5

Scope 4

Scope 3

Scope 28

Scope 2

Scope 14

Scope 13

Scope 12

Scope 11

Scope 10

Scope 1

Scope

Heat

V1

V2

A

Neutral

RF Power 45 kV

c

12

RF Power

Heat

V

A

B

C

Neutral

RF Filaments450 V, 60 Hz

com

A

B

C

a

b

c

RF Filaments

RESET

a1

b1

c1

a2

b2

c2

a3

b3

c3

a4

b4

c4

+DC1

-DC1

+DC2

-DC2

+DC3

-DC3

+DC4

-DC4

Quad passiveRectifier

+DC1

-DC1

+DC2

-DC2

+DC3

-DC3

+DC4

-DC4

+DC out

-DC out

Quad filter

VAC out

IAC out1

+DC in

-DC in

a

b

c

Quad DC-ACconverters & filters

a1

b1

c1

a2

b2

c2

a3

b3

c3

a4

b4

c4

+DC1

-DC1

+DC2

-DC2

+DC3

-DC3

+DC4

-DC4

Quad 45 kVdc passiveRectifier

+DC1

-DC1

+DC2

-DC2

+DC3

-DC3

+DC4

-DC4

+DC out

-DC out

Quad 45 kVdc filter

A1

B1

C1

A2

B2

C2

A3

B3

C3

A4

B4

C4

a1

b1

c1

a2

b2

c2

a3

b3

c3

a4

b4

c4

Quad 4.5 kV / 35 kV Xfrmr

Pier Side

Heat

V1

112.5 V

Neutral

Optics112.5 V, 60 Hz

c

12

Optics

On/OffTurbine

On / Off 9

On / Off 8

On / Off 7

On / Off 6

On / Off 5

On / Off 4

On / Off 3

On / Off 2

On / Off 15

On / Off 14

On / Off 13

On / Off 12

On / Off 11

On / Off 10

On / Off 1

In1

In2Out1

OR1

In1

In2Out1

OR

3

Multimeter1

3

Multimeter

Created by CEMCenter for Electromechanics of the

University of Texas, Austinand NPS

the Navy Postgraduate SchoolMonterey, California

for theOffice of Naval Research of the US Navy

September 30, 2009

Heat

V1

V2

V3

A

Common

Magnets 2600 V dc

c

12

Magnets 2

Heat

V1

V2

V3

A

Common

Magnets 1600 V dc

c

12

Magnets 1

com

A

B

C

a

b

c

Injector

i+

-

i+-

i+ -

i+ -

i+ -

i+ -

Heat

V1

V2

V3

A

B

C

Neutral

Housekeeping112.5 V, 60 Hz

com

A

B

C

a

b

c

Housekeeping

Hot Stand By

Amps

Volts

+ DC

- DC

Gun Injector

UnderWay

[Turb]

RESET

PierSide

FIRE

HotStandBy

Injector

Injector

[Turb]

FIRE

1

Enable

0

Disable

i+ -

i+-

i+ -

Heat

RPM1

RPM2

RPM3

A

B

C

Neutral

Cryogenics 2450 V, 60 Hz1

com

A

B

C

a

b

c

Cryogenics 2

Heat

RPM1

RPM2

RPM3

A

B

C

Neutral

Cryogenics 1450 V, 60 Hz

com

A

B

C

a

b

c

Cryogenics 1

Heat

RPM1

RPM2

RPM3

RPM4

A

B

C

Neutral

Cooling4,160 V, 60 Hz

com

A

B

C

a

b

c

Cooling

Heat

V1

V2

V3

A

B

C

Neutral

Computers112.5 V, 60 Hz

com

A

B

C

a

b

c

Computers

C4

C3

C2

C1

A

B

C

a

b

c

Breaker 6

A

B

C

a

b

c

Breaker 4

A

B

C

a

b

c

Breaker 2

Breaker 1

Heat

V1

V2

A

B

C

Neutral

Beam Dump4,160 V, 60 Hz

com

A

B

C

a

b

c

Beam Dump

Heat

RPM1

RPM2

RPM3

A

B

C

Neutral

Beam Control450 V, 60 Hz

com

A

B

C

a

b

c

Beam Control

In1Out1

AUTO2

In1Out1

AUTO1

In1Out1

AUTO

VAC outa in

b in

c in

a out

b out

c out

AC load meas.

+Vdc out

Common1

+Vdc in

Common

6,000 vdc / 800 Vdc1

+Vdc out

Common1

+Vdc in

Common

6,000 vdc / 800 Vdc

RPM

Current

Vab

a1

b1

c1

a2

b2

c2

a3

b3

c3

a4

b4

c4

4-windingsPM Generator

Injector Vab

Injector Volts dc

Injector Amps dc

600 VDC

45 kVDC

4160 VAC

450 VAC

112 VAC

IPS/6000 VDCFEL Simulink Model

High fidelity models exist for the other loads, as well as a combined hi/fi model.

Perturbations Induced by Starting FEL Cooling Units

4.15 4.16 4.17 4.18 4.19 4.2 4.21 4.22 4.23 4.24 4.25-800

-600

-400

-200

0

200

400

600

800Perturbation detail on the 450 Vac bus and 600 Vdc bus

Time, s

450

Vac

bu

s: li

ne-

to-l

ine

Vo

lts

(blu

e), l

ine

Am

per

es (

gre

en, /

100)

600

Vd

c b

us:

Vo

lts

(red

)

600 VDC bus volts

450 VAC bus line-to-line volts

Line amperes/100

450 VAC & 600 VDC Buses

Volts

, Am

ps

Time (s)

4.2 4.205 4.21 4.215 4.22 4.225 4.23 4.235 4.24-3

-2

-1

0

1

2

3x 10

4

Time, sGen

era

tor

lin

e A

mp

eres

(p

has

es

a o

f ea

ch o

f th

e fo

ur

3-p

has

e w

ind

ing

s)Reflection of one perturbation at the generator

Perturbations Induced by Starting FEL Cooling Units

Four, 3-Phase WindingsG

ener

ator

Lin

e Am

pere

s

Time (s)

Loss of One Phase of Main Generator

4.98 4.982 4.984 4.986 4.988 4.99 4.992 4.994 4.996 4.998 5-2

-1.5

-1

-0.5

0

0.5

1

1.5

2x 10

4 Opening of phase a1 of generator at t = 4.988

Time, s

Gen

erat

or: l

ine

a1 A

mpe

res

(blu

e), l

ine-

to-li

ne a

1-b1

Vol

ts (g

reen

)

4.95 5 5.053.5

4

4.5

5

5.5

6x 10

4

Time, s

DC

Bu

s: A

mp

ere

s (b

lue)

, Vo

lts

(gre

en, x

10)

Impact on dc bus of opening of phase a1 of generator at t = 4.988Line a1 (A)

Line-to-linea1-b1 (V)

DC bus (A x 104)

DC bus (V x 104)

Low Impedance Fault on 450 VAC Bus

4.95 5 5.05-2500

-2000

-1500

-1000

-500

0

500

1000

1500

2000

2500

Low impedance line-to-line fault on 450 Vac bus supplyingSonar and EM Gun Mount at t = 5.012 s and cleared in ~2.5 cycles

Time,s

450

Vac

bu

s: li

e-to

-lin

e V

olt

s (b

lue)

, lin

e A

mp

eres

(g

reen

, /10

0)60

0 V

dc

bu

s: V

olt

s (r

ed)

450 VAC busline-to-line (V)

600 VDC bus (V)

Line Current(A/100)

Electric Ship Simulator Concept

NPSElectric Ship

Simulator

NPSElectric Ship

Simulator

FELFEL

Rail GunRail Gun

RadarRadar

SonarSonar

PropulsionPropulsion

LaWSLaWS

Operator(Admiral, students)

Operator(Admiral, students)