Team MembersHeather Bartlett

-Trigger Package Design (PCB, PIC)-Warning Lights

Andrew Read

-PC Software -Communications -System Design/Integration

Stephen Whitfield

-Siren-PCB packaging

Stanislaw Gryzbowski

Advisor

Other Advisors:-Mr. Clay Taylor-Dr. Ginn

OutlineIntroduction

Problem

Solution

Constraints

Design Improvements

Testing plans

Questions

Problem

The MSU High Voltage Lab is in need of a new control system for its impulse generator.

Gap Motor

Transformer / Rectifier

75kVDCvariable

150-300VACpeak

variac

240VAC (RMS)

Current SystemManually Controlled

Firing Circuit exists but is not connectedStepper motor will be installed by HVL

Manually Controlled

Breaker

Interlock

Warning Light

Impulse GeneratorHow does it work?

An impulse generator produces short pulses of high-voltage.

‘n’ number of capacitors charged in parallel to a voltage ‘V’

Capacitors connected in series

System is triggered

Creates lightning!Gap Motor

Why is it important?

The impulse generator is used to run tests on equipment that can be put under high voltage stress. These tests help ensure protection to the equipment.

[1]

[2]

Gap Motor

PE-BasedVoltage Control

PE-BasedVoltage Control

240VAC (RMS)

New System

ControllerController

+/-75kVDCvariable

150-300VACpeak

Transformer / Rectifier

v(t) i(t)V

Motor Indexer

Firing Ckt

PC ControlPC Control

Breaker

Interlock

Practical ConstraintsHealth & Safety

Must tie into lab safety interlock system

New alarm siren should be loud, but not too loud

Sustainability High Energy Transients Electromagnetic Interference

Technical ConstraintsTransformer Input

Voltage and Current monitoring

Transformer Output +/-75kV DC (1% accuracy)

Input Voltage: 150 VAC

Output Voltage:+75kVDC

+/-75kVDCvariable

150-300VACpeak

Transformer / Rectifier

C C

C C

Firing Circuit

Stepper Motor

Stepper MotorIndexerTo Controller

Gap Spacing 3-7.7cm range on gap spacing 1mm tolerance

Technical Constraints

Technical Constraints

Voltage Controller 20A max current throughput 150-300VAC output range

OutlineIntroduction

Problem

Solution

Constraints

Design Improvements

Testing plans

Questions

Warning Siren Testing

Astable Config.

MonostableConfig

Warning Siren

•Astable Operation- produces ‘square wave’-output continually changes between ‘low’ and ‘high’

•Monostable Operation-features RC circuit to set the output duration

Warning Siren

•Will feature a speaker with an integrated amplifier

•Should be capable of outputting in between 50-60dB

Voltage Controller

UPS-StyleVoltage Control

UPS-StyleVoltage Control

ControllerController

Transformer / Rectifier

+/-75kVDCvariable

150-300VACpeak

V

PC ControlPC ControlDesired Voltage

Duty cycle

Prototype Design

Buck-Boost Stage

Controller

InverterPower Supply120 VAC Rectifier

Voltage Controller Testing

Boost Controller

Boost Converter

Inverter

Voltage Controller Design

Voltage Controller Design

Voltage Controller Testing

PCB populated in stages and supplied with 120VAC (50% design rating)

Low voltage components on separate PCB can be tested and troubleshot separately

Voltage Controller Testing

Setting Desired Measured % ErrorBuck-Boost Max Output 340VDC N/A #DIV/0!Buck-Boost Min Output 170VAC N/A #DIV/0!Inverter Max Output 300VAC N/A #DIV/0!Inverter Min Output 150VAC N/A #DIV/0!

Controller DesignP

IC18

F46

85

Stepper Motor DriverMLP08641

Clo

ck +

Clo

ck -

Dire

ctio

n +

Dire

ctio

n -

On/

Off

+

DACMAX517

MAX3222 RS232

Rou

t

Tin

RX

TX

Vdd

Gnd

SD

A

SC

L

Output to Voltage Controller

Stepper Motor

SCLSDA

Input from VC

AN0

Warning Light (LED)

Warning Siren

RA4RA5

RC5Signal to Trigger

CCP1

RB1

RB3RB4RB5

Software Testing• Move stepper motor to desired distance

• Wait for transformer output voltage to equal the desired Charging Voltage

• Yes• Signal is sent to triggering device• Stepper motor is returned to starting position

• Turn warning Siren and Light on

• Would you like to fire the trigger (Y/N)?

• No• Signal is not sent to triggering device• Stepper motor is returned to starting position

Controller TestingStepper Motor • 0 revolutions = 30 mm• 2 ½ revolutions = 77mm

Stepper Motor Driver• 200 steps/rev• PWM signal: one step/ period

Controller Testing Plan

• Run new tests for DAC Output from Controller to Voltage Controller

• Compare Voltage Controller Outputto desired value.

• Measure Sphere Gap spacing once installed in the HVL.

Timeline

January February March April

PCB Design

Hardware Testing

Software Testing

Installation

References

http://sciam.com/media/inline/000DBD54-3835-1C71-84A9809EC588EF21_arch1.jpg

http://www.tuvps.co.uk/articles/Military-lightning.jpg

Mohan, Ned. Power Electronics. Minneapolis, MN. 2007.