nasa sgslr power and lightning protection system 232...thermally fused metal oxide varistors (mov)...
Post on 15-Mar-2020
7 Views
Preview:
TRANSCRIPT
NASA SGSLR Power and Lightning Protection System
H. Donovan1, J. McGarry
2 , A. Nelson
1, D. Patterson
1, F. Hall
1, P. Christopoulos
1, D. Panek
1, E. Ridge
1
1 KBRwyle Technology Solutions LLC, Lanham, MD, USA
2 NASA Goddard Space Flight Center, Greenbelt, MD, USA
Abstract: The Space Geodesy Satellite Laser Ranging (SGSLR) Lightning Protection System will use a multi-tiered system to protect the station s sensitive electronic equipment and instrumentation. Without such protection, a ranging system can incur extensive electronic equipment damage and/or lengthy operational interruptions. As an example, on June 14, 2015, severe lightning occurred at the Goddard Space
Flight Center (GSFC), location of the SGSLR Prototype, the Next Generation Satellite Laser Ranging system (NGSLR). When attempting to power on the various equipment of the NGSLR the following workday, it was realized that the system suffered significant damage to almost all major subsystems: meteorological, communications, timing, aircraft avoidance, optical bench, computer, security, and Heating
Ventilation Air Conditioning (HVAC). The adjacent Mobile Laser Ranging System (MOBLAS) 7 station system incurred damage as well because of common signal paths between the systems. Another example of severe lightning damage occurred this year at the McDonald Laser Ranging System (MLRS) in Fort Davis, Texas, US. As a result of these incidents, a multi-tiered lightning protection system was
designed and has been implemented for the GSFC Goddard Geophysical and Astronomical Observatory (GGAO) SGSLR and will be installed at all of the SGSLR sites. System power, station grounding, and data and communications have all been addressed to greatly minimize the effects of a lightning strike and/or associated power surges. This poster describes the resulting new lightning protection system as it
is being installed at the SGSLR at the GGAO.
2019 ILRS Technical Workshop in Stuttgart, Germany
Data & Communications External Interfaces
HVAC 2HVAC 1
Anemometer
GPS Antenna
Meteorlogical Sensor
Fiber for monitoring status/control
HVAC Control
MASER
Ph
on
e a
nd
Inte
rnet
LHR
S M
ag
net
ron
Fir
e C
on
firm
ati
on
fo
r V
LBI
Plan for SGSLR
In Server Racks
In Shelter
FT
10
Mh
z a
nd
1 P
PS
*
SPPower Fence
FT
FT
FT
10 Mhz & 1 PPS
SP
Vaisala
SkyCamera
LHRS
ELIMINATE COPPER CONNECTIONS TO THE OUTSIDEData & Communication Diagram
FT
FT
FT
FT
FT
FT
FT
FT
SP
SP
SP
SP
SPFT
VLBI
FTLHRS Magnetron Fire Confirmation for VLBI
STALASBuilding
FT
FJB
Communication link with SGSLR
FJB
FT
Co
mm
un
ica
tio
n li
nk
wit
h S
GSL
R
To minimize damage
caused by lightning to
external data and coms
interfaces, SGSLR uses
fiber optic transceivers.
Data interfaces for the
LHRS, Pressure and
Temperature and
Humidity, sensors, Sky
Camera, Anemometer,
Horizontal Visibility and
Present Weather sensors,
GPS antenna and internet/
voice comms are all
optically coupled between
the sensor outside the
shelter and equipment
inside the shelter. Grounding, Counterpoise, and Air Terminals
The SGSLR uses a counterpoise
ground system. A heavy gauge
copper cable encircles the perimeter
of the Shelter and is buried beneath
the ground surface. Ground rods
were driven several feet into the earth
and placed every 2 meters, then cad
welded to heavy gauge copper cable.
On the top of the Shelter, a heavy
gauge braided copper cable was
placed around the roof parameter then
connected to the counterpoise. Air
terminals were placed at the four
corners of the roof and midway length
wise of the building. The ground field
was constructed to provide minimal
earth ground resistance with a goal of
no more than 5 ohms. Inside the
building individual heavy gauge
copper cables are connected directly
to ground bus bar in each equipment
rack then to a copper bus bar behind
the racks. The bus bar behind the
racks is then directly connected to the
counterpoise.
Lightning & Power Protection Equipment
Eaton 9PXM 12S 16K
Uninterruptable Power Supply
On June 14th, 2015, the NGSLR experienced a
lightning strike. Outside security cameras recorded
video of the storm as it passed over the system.
The storm was short and intense with heavy rain
and many lightning strikes. Though the security
system was damaged, video was able to be
extracted from the DVR. Heavy rains and lightning
began at 21:18 local time. At 21:35 local time the
NGSLR security cameras stopped functioning; it is
believed this is when the damaged occurred. The
image to the left is a frame from the security video
showing a lightning strike at the GSFC GGAO in the
background and the NGSLR in the foreground.
Image to the right is of the NGSLR.
The Lightning Strike at NGSLR
The SGSLR incoming power will be conditioned using
multiple systems. A suppression filter system using
thermally fused Metal Oxide Varistors (MOV) will
significantly reduce power spikes from lightning or other
equipment outside of the SGSLR. The suppression filter
system has Ethernet connectivity to communicate time
stamped events of magnitude and duration sags, surges,
dropouts, frequency, etc. as well as health of the
suppression system. The Uninterruptable Power
System (UPS) will further filter the incoming power and
compensate for power spikes, sags, surges, line
frequency changes and interruptions protecting the
equipment and instrumentation. The UPS has a
computer interface allowing monitoring of each of the 5
power modules. Power Distributions Units (PDU) are
used in each rack to prove power control and monitoring
for each piece of equipment. Power consumption can
be monitored to understand instrument health.
Equipment external to the SGSLR shelter such as the
Laser Hazard Reduction System (LHRS) and the
meteorological equipment will obtain power via the UPS
and PDUs receiving protection from incoming power
disturbances. MOV surge suppressors will be
connected to the power lines at the shelter interface and
the equipment interface to minimize the effects of
lightning disturbances along the external equipment
power line.
Rack 3
Three Phase
Transformer
Power
Fence
Counterpoise
Air Terminal
1
Th
ree p
hase f
eed
with
ne
utr
al an
d
safe
ty g
roun
d
SP
In Shelter
HVAC 1
Rack 2
1 Five wire, three phase feed (A, B, C) system with
neutral and ground isolated back to the tranformer.
2PDU units are used to provide, monitor and
control (ON/OFF) power.
3UPS unit is used to provide, monitor and control
(ON/OFF) conditioned power.
DRAWING NOTES
Rack 4
PDU 4
Laser
Motion Control
Rack 1
Computers
Dome Control
Electronics
Dome Backup
Battery
HVAC 2
UPS
SP
Breaker
box
Servo Digital
Controller
Range Control
Electronics
Laser Safety
Eqpt.
Networking
Eqpt.
Monitoring Eqpt.
Time and
Frequency (TFS)
Equipment
PDU 3PDU 2PDU 1
Earth Ground
Drawing D-828a
SP
JB Electrical Junction Box
Surge Protection
KEY
UPS
PDU
Uninterruptable Power Supply
Power Distribution Unit
Three phase feed (5 wire)
Three phase (5 wire)
Single phase
Conditioned single phase
Counterpoise (leads to ground field)
SPJB
SPJB
SPJB
SPJB
SPJB
SPJB
SP
GPS Antenna
Anemometer
TPH Sensor
HVP Sensor
SkyCamera
Aircraft Detect
2 2
3
2
2
SGSLR Power Distribution Protection
The lightning storm damaged 6 of the 9 NGSLR subsystems: Computer,
Meteorological, Time and Frequency, Safety, Shelter, and Optical Bench. Even
though the NGSLR equipment was connected to UPS, many components were still
damaged, and many beyond repair. These components were the Pseudo Operator
(POP) and Device Access Manager (DAM) computers, the Paroscientific MET4, the
TrueTime XL-DC time and frequency unit, the LHRS, the IO chassis, Heating
Ventilation Air Conditioning HVAC unit 2, security system monitor/DVR/outside
cameras, Risley prism controller, and telephones.
The lightning strike occurred near NGSLR causing a high voltage and current surge
that entered the system through multiple paths. External copper communications
lines for the telephones and internet are two likely paths as the associated
equipment was damaged beyond repair. The internet line was connected to a
Network Switch then to the VME Chassis and all were damaged. The VME based
POP and DAM computers share various serial and parallel communications cards
which connect to other equipment in NGSLR. The VME parallel interface were
connected to the IO Chassis, which in turn, connects to the LHRS Local Control
unit, both of which were damaged. The MOBLAS 7 LHRS, which was connected to
the NGSLR Local Control unit, was also damaged. The LHRS temperature control
unit located in the NGSLR shelter failed, as well as the temperature sensor for the
controller, which is located outside. The security camera system was connected to
two outdoor cameras and an HDTV monitor, all of which were damaged. The
compressor for the HVAC unit 2 failed along with a controller board power supply.
Equipment connected to the UPS systems did not receive damage.
Communications and data interfaces to the outside world were the primary cause.
STALAS
NETWORK SWITCH (LINK TO NASA INTRANET)
A Module B Module C Module D Module
T Z W
DELAY
OU
T
T Z W
DELAY
OU
T
T Z W
DELAY
OU
T
T Z W
DELAY
OU
T
PHILIPS
SCIENTIFICLRO Delay (6915 CFD)D
EL
AY
IN
OU
TO
UT
TT
L
1
2 4
3SECURITY DVR
Outside
CamerasInside
Cameras
MV
P
CO
NT
RO
LL
ER
S
J1 J2 J3 J4 J5 J6 J7 J8
J9 J10
10 MHz IN
CH1
J11 J12
J13 J14
CH1TTL NOT
CH2TTL NOT
CH3TTL NOT
CH0TTL
CH2 & CH3TTL NOT
CH2NIM
CH3NIM
CH0TTL NOT
RANGE GATE GENERATOR
JDB1 JDB4JDB2MSBC
JDB3LSB
CH0TTL
CH2TTL
CH3TTL
CH1TTL
SLR LASER (Photonics Industries)
LRO LASER (Northrop Grumman)
SCSI
I/O BOX
IO CHASSIS (IOC)
SLR START
SMATRIGGER (TTL) BNC
Hamamatsu MCPModel # R5916U-64
GPS TIME & FREQ. RECVR.TRUETIME XL-DC
ANT5 MHz5 MHz 10 MHz 10 MHz IRG-B1 PPS
SERIAL I/O
RS-232
2k OUT(NIM)
1 PPSOUT(NIM)
10 MHzIN
1 PPSIN
10 MHz OUT
2k OUT(TTL)
LASER FIRE
5 MHz5 MHz 10 MHz 10 MHz
COMPUTER CLOCK
SYNC INTERFACE (CCSI)In House Built Timing Box
ICC COMPUTER
IN
CONNECTION TYPE:
Analog*
10 MHz*
NIM*
TTL*
RS-232
Fiber Optic
Other
1
DISTRIBUTION AMP. SYMMETRICOM 6502
6502987654321 10
OUTPUT
GATING POWER
SUPPLY (GM150-20)
AMPLIFIER PHILLIPS SCIENTIFIC (774)
DISCRIMINATORTENNELEC (TC454)
INININ IN
OU
T
OU
T
OU
T
OU
T
1 2 3 4
High Voltage Power
Supply (Bertran 315)
DISCRIMINATORTENNELEC (TC454)
2
MASER 10 MHz
VLBI MASER SYMMETRICOM SIGMA TAU
PO
P
CO
MP
UT
ER
DA
M
CO
MP
UT
ER
P3
P4
VM
E C
HA
SS
IS
1
RISLEY PRISM MVP
CONTROLLERS
2
MET4 WEATHER
DEVICE
RS
23
2
STARTDIODE
SLR START DIODEMonsanto MD2 Fiber Optic
Transcievers (Typical)
10 MHz
7
Drawing Notes:
Please refer to drawing D-08 for a listing of all
notes and callouts on this drawing.
9
9
8
TO THE EVENT TIMER
TO THE TIMING
BOX
TO THE ICC
TO THE GPS
TIME AND FREQ.
RECIEVER
TO POP ON THE
VME CHASSIS
TO THE ICC8
10
11
68 PIN SCSI II CABLE
11
3
5
4
12
12
1 PPS
COMPARATOR INPUT DATA(SCSI)
COMPARATOR INPUT DATA(IDC)
COMPARATORTEST PULSE
OUT
CH9 CH10 CH11 CH12
OUTPUT DATA
J1
J10
CH5
J6
CH1
J2
J11
CH6
J7
J12
CH7
J8
NIM INPUT DATA
CH2
J3
CH3
J4
J13
CH8
J9
J16
CH4
J5
10 MHZ IN
J17
J15
J14
EVENT TIMER
OSCILLOSCOPE
FIBER OPTIC CABLE
6
* Uses coaxial cable
Located at VLBI
1414
Located at NGSLR
WINDMILL
ANEMOMETER
TO CONNECTOR ON BACK OF RACK (SEE NOTE C, DRAWING R-02 FOR DETAILS)
CR-02
ZFDC-20-3A
IN
CPL
INVERTINGTRANSFORMER
LHRS LOCAL
CONTROLLER
Mount Controller
EM ERGEN CY
STOP
OFF
ON
POW ERSHUTTER
EM ISSIO N
NORTHROP GRUMMAN
OFF ON
Photonics Industries
POW ER
Connector # Function
P1 Commands & Status (To / From POP)
P2 LRO Laser Beam Block
P3 2 kHz Laser Beam Block
P4 MCP Shutter
P5 Star Camera Shutter
P6 Remote Beam Block Control Box (Enable/Disable)
P7 LRO Laser ND Insert
P8 2KHz Laser ND Insert P9 Remote Control Box
P10 MCP ND Insert
P11 Cable Integrity
P12, P13 Spares
28
Hz
MC
P W
ind
ow
Window / Window
Co
mm
an
d a
nd
Sta
tus
Command and Status
Window / Window
2 kHz
LRO Laser Tr igger
SLR Laser TriggerMCP Gate
5 MHz 1 PPS1 PPS
IN OUT
1 PPS
12 V DC Power
Supply
DOME
CONTROLLER
STARTDIODE
LRO START DIODEMonsanto MD2
INVERTINGTRANSFORMER 1 2 3
1. Aircraft Detect2. 20 degree Elevation Switch3. Radar Command (Slave/Manual)
Co
mm
an
d a
nd
Sta
tus
MOBLAS 7 TRAILER
IO Chassis "P Series" Connections
Remote Beam Block
Control Box (Enable/
Disable)
Remote
Enable Box
14 14
1 PPS DISTRIBUTION
TO THE
LHRS 16
16
PIB
TO PIB
15
GA
TE
4 C
HA
NN
EL
S
GA
TE
CO
MM
ON
A Module B Module C Module D Module
T Z W
DELAY
OU
T
T Z W
DELAY
OU
T
T Z W
DELAY
OU
T
T Z W
DELAY
OU
T
LRO START
LRO START
SLR START
Test Point
J1J1P2
P5
P8
P11
P3
P6
P9
P12
P4
P7
P10
P13
J9
J17
J21
J2
J10
J18
J22
J3
J11
J19
J23
J4
J12
J20
J24
J5
J13
J6
J14
J7
J15
J8
J16
J25 P1
MOBLAS-7 FIRE
MOBLAS-7 1 PPS
LHRS HVAC
CONTROLLER
HUMIDITY
LHRS FIRE
IOC Interface
NETWORK SWITCH
CAMERA
COMPUTER
RAT DICOM
NETWORK
SWITCH
X X
X
X
X X
Ethernet
Ethernet
X
X
X
X X
KeyDamaged, unit not
working correctly
Damaged port, but
unit still functional
Outside system
Outside system
VIASALA
INSTRUMENT
Damaged outside unit
MOBLAS 7
DIS
CR
IMIN
AT
OR
LHRS
RADOME
TEMPERATURE
17
17
LHRS
RADOME
TEMPERATURE
Telephone
System #1
Telephone
System #2
STALAS
TELEPHONE
CONNECTION
NGSLR System Damage
top related