Blackout Mitigation

1
Blackout Mitigation

• Edgar Roman
• Michelle Graden

2
Why Blackout Mitigation?

• August 14th blackout
• California blackouts
• Combines two disciplines
• Power electronics
• Power systems

3
Introduction

• Controller
• Voltage sensing capabilities
• 4 Priority loads
• Bus voltage
• Regulates the load on the system
• Power supplies
• 4 buck converters with feedback
• Disturbance controller

4
Schematic of Circuit Layout
5
Circuit Layout
6
Controller

• Senses soft bus voltage
• Turns off loads depending on soft bus voltage and
  priority settings
• Adds loads back into system once stability is
  reached
• Von Voff ?V

7
Controller Flow Diagram
8
Soft Bus Voltage Sensor

• Originally voltage divider
• Op-amp circuit
• Wider range of inputs

9
Priority Settings

• User defined
• Low priority drops out first, turns back on last
• High priority drops out last, turns back on first
• Voltage range

10
Controller Layout
11
Power Supplies

• 4 dc-dc Buck Converters with feedback
• Two 42V to 12V (50 W)
• Two 42V to 5V (20 W)
• Load regulation ?2
• Line regulation ?2 ripple voltage output
• .

12
5V Buck Converter with Feedback
13
12V Buck Converter with Feedback
14
The Disturbance Controller

• MOSFET switch with transient load
• Doubles output current for a period of time
• 3 different output waveforms

15
Disturbance Flow Diagram
16
Module Testing

• Buck Converter tests
• Open-loop
• Feedback
• Controller tests

17
Integration Testing

• Started up initially with one converter

18
Soft Start?

• Regulates current from ramping up too quickly
• Connected various-sized capacitors to PWM chip
• Ended up disabling converters

19
Controller Delay

• Delay controller output
• Keeps controller from seeing soft voltage dip too
  soon

20
Resistor at Source

• Improves controller delay
• Limits current flow to inductor, which creates
  less of a current spike

21
Possible Improvements

• Average soft bus voltage over time
• DSP chip instead of PIC
• Improve circuitry

22
Summary

• Controller regulates when converters turn on and
  off
• Constant output voltage with feedback
• Disturbance controller created three different
  types of stress on the system

23
Special Thanks

• Joseph Mossoba
• Hope you got your research done!
• Marty Cantzler
• Youre a PIC whiz!