Intelligent Surge
Protection Device
EEL 4906 Engineering Design I and Professional Issues
TEAM MEMBERS:
CRUZ, JAIME E.
DOBBS, MICHAEL
GUZMAN, FRANK
OGUNDERE, ADEBOWALE
WALLACE, RICHARD
ADVISOR:
DR. PARIS WILEY
INSTRUCTOR:
SELCUK KÖSE
CORPORATE PARTNER:
Jaunary 26th 2015
Introduction
 SPD’s are electrical devices typically installed in
power distribution panels, process control systems,
communications systems, and other heavy-duty
industrial systems, for the purpose of protecting
against electrical surges and spikes, including those
caused by lightning.
 However, none of the SPD’s in the market allow for
remote monitoring of the key components, and they
are limited to certain electrical characteristics.
Our Design Concept
 Intelligent Surge Protection Device
 Remote monitoring/reporting
 User friendly interface (PC software)
 Improve electrical characteristics of SPD
Fuses
 Metal-Oxide Varistors (MOV’s)
 Conducting wires
 Avalanche diodes



Sensing circuit to measure the degradation of the unit as a
whole.
Improve the external design (housing)
SPD FUNCTIONAL DIAGRAM
Areas of Research
 Overvoltage sensing circuit
 Develop a circuit
 Use an existing patent available to the public
 Use existing proprietary sensing circuit and treat it as a black
box
Areas of Research
MOV’s and Silicon
Avalanche Diodes
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Metal Oxide Varistor
(MOV):
Highest energy capability
Excellent reliability
Consistent performance
Better mechanical
connectivity for paralleling
multiple components.
Non-liner clamping curve
gradually degrades over
repeated use (only at high
surge levels), moderate
capacitance.
Silicon Avalanche
Diode(SAD):
Flatter clamping curve
Excellent reliability
Consistent performance
Very low energy capability
Expensive.
Varistor IV Curve
Avalanche Diode IV Curve
Transient Voltage
Suppressor
Diodes
Areas of Research
Silicon
Avalanche Surge
Suppressor
 SASD uses a silicon
based diode, similar
to a Zener Diode.
 SASD response
times are faster: 1 ps
to 10 ps, compared
to 1 ns to 10 ns for
MOVs.
 They have a sharper
bend in the curve
around the
breakdown voltage;
As a result, they can
clamp closer to the
normal peak voltage
MODES OF PROTECTION - LINE CONNECTION
L1
L2
L3
Neutral
7 Modes of Protection
Ground
Avalanche Diodes will be added in a way to assist the reaction
time of each Varistor (MOV)
Simplified Safe/Fail Circuit Diagram
MOV
MOV
MOV
Small Magnet Attached
to MOV’s fail Indicator
Hall Effect Sensor
US1881
Output = High/Low
Micro Controller
Info. via
Wireless
Comm.
Info.
Received
at User
PC
Implementation of the Hall Effect Circuit
Hall Effect
Senor Attached
Here
Magnet will
be Attached
Here
Areas of Research
 Arduino UNO Microprocessor



Process the information coming
from the various sensors in the
device.
Conveys the information to the
Wi-Fi module.
Process incoming requests from
remote users.
 Two-way user interface
software

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Auto-reporting capabilities
defined
by the user
User will be able to monitor the
status
of the SPD’s in real time.
Tools available to create GUI:

QT Project
Areas of Research
 Wireless Transmission
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Existing Wi-Fi network is
required.
 IEEE 802.11 a/b/g/n
HF-A11 modules use UART
interface which include 4
general signals:
TXD/RXD/RTS/CTS
Add RS-232 chipset to convert
the signal to RS-232 voltage to
communicate with the device
(sensors).
Sleep mode capability while
maintaining
association with the access
point.
Areas of Research: Housing Redesign
Proposed
Current
Tools Available:
SolidWorks is solid modeling
CAD (computer-aided design)
software.
3D Printing
UPGRADES TO
THE SPD
PRODUCT SPECIFICATIONS
EXISTING PRODUCT SPECIFICATIONS
Enhancements
Nominal Discharge
> 30kA
20kA
Current Rating
Maximum Surge
100kA/mode; 200kA/
Current Rating
phase
Fault Current
200kAIC
(SCCR)
Product Design
Modular per mode/phase
Protective
Thermal Protected MOV’s
Components
Thermally Protected MOV’s and
TVS Diodes
System Protection
30A Surge Fuses
50A Surge Fuses
Connecting Leads
36 inches 10AWG
36” #8 AWG
Recommended
30A
50A
Breaker Size
Response Time
< 1 Nanosecond
Frequency
50/60Hz
Status Indicators
Protection Status, Voltage
Electronic MOV Failure Status,
Presence, Mechanical MOV
Surge Counter
failure
Enclosure Type
Metal
Installation
Indoor or Outdoor
Thermo-Plastic
Location
Weight
4.4lbs
3.8lbs
Intelligent Features
Static Device
Remote reporting and monitoring
via Wi-Fi, Sustained Overvoltage
Notification, Surge Notification
Technical Risks
 Transient Sensing Circuitry
 Setting the threshold voltage for detection
 MOV and Avalanche Diodes Performance
 Not switching fast enough could damage Diodes
 Failed MOV/Diode Detection Circuitry
 False indication could leave the user unprotected
 Hall effect sensor performance in high current environment
 Wireless transmission
 Location may not have access to a Wi-Fi spot or weak signal
Tentative Timeline
QUESTIONS?
VISIT OUR WEBSITE
HTTP://SMARTSURGEPROTECTOR.WORDPRESS.COM/
CONTACT ANY OF US
CRUZ, JAIME
JCRUZ15@MAIL.USF.EDU
DOBBS, MICHAEL
MDOBBS@MAIL.USF.EDU
GUZMAN, FRANK
FGUZMAN@MAIL.USF.EDU
OGUNDERE, ADEBOWALE
AOO@MAIL.USF.EDU
WALLACE, RICHARD
RBWALLACE@MAIL.USF.EDU