Team Members Heather 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

Outline Introduction 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 75kVDC variable VAC peak variac 240VAC (RMS) Current System Manually Controlled Firing Circuit exists but is not connected Stepper motor will be installed by HVL Manually Controlled Breaker Interlock Warning Light

Impulse Generator How 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-Based Voltage Control PE-Based Voltage Control 240VAC (RMS) New System Controller +/-75kVDC variable VAC peak Transformer / Rectifier v(t) i(t) V Motor Indexer Firing Ckt PC Control Breaker Interlock

Practical Constraints Health & 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 Constraints  Transformer Input  Voltage and Current monitoring  Transformer Output  +/-75kV DC (1% accuracy)‏ Input Voltage: 150 VAC Output Voltage: +75kVDC +/-75kVDC variable VAC peak Transformer / Rectifier

CC CC Firing Circuit Stepper Motor Indexer To Controller  Gap Spacing  3-7.7cm range on gap spacing  1mm tolerance Technical Constraints

 Voltage Controller  20A max current throughput  VAC output range

Outline Introduction Problem Solution Constraints Design Improvements Testing plans Questions

Warning Siren Testing Astable Config. Monostable Config

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-Style Voltage Control UPS-Style Voltage Control Controller Transformer / Rectifier +/-75kVDC variable VAC peak V PC Control Desired Voltage Duty cycle

Prototype Design Buck- Boost Stage Controller Inverter Power Supply 120 VAC Rectifier

Voltage Controller Testing Boost Controller Boost Converter Inverter

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

Controller Design PIC18F4685 Stepper Motor Driver MLP08641 Clock + Clock - Direction + Direction - On/Off + DAC MAX517 MAX3222 RS232 Rout Tin RX TX Vdd Gnd SDA SCL Output to Voltage Controller Stepper Motor SCL SDA Input from VC AN0 Warning Light (LED)‏ Warning Siren RA4 RA5 RC5 Signal to Trigger CCP1 RB1 RB3 RB4 RB5

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 Testing Stepper 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 Output to desired value. Measure Sphere Gap spacing once installed in the HVL.

Timeline JanuaryFebruaryMarchApril PCB Design Hardware Testing Software Testing Installation

References C71-84A9809EC588EF21_arch1.jpg C71-84A9809EC588EF21_arch1.jpg lightning.jpg lightning.jpg Mohan, Ned. Power Electronics. Minneapolis, MN