ESA UNCLASSIFIED - For Official Use Avionics-Power interfaces standardisation An exportable approach? Ferdinando Tonicello, TEC-E, Electrical Department 16/10/2020 Power and Avionic Work Group* Presented by * Participants revealed in slide 13
ESA UNCLASSIFIED - For Official Use
Avionics-Power interfaces standardisationAn exportable approach?
Ferdinando Tonicello, TEC-E, Electrical Department
16/10/2020
Power and Avionic Work Group*
Presented by
* Participants revealed in slide 13
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 2
Avionics-Power interfaces standardisation
Outline
• Preamble
• Motivation
• Subjects and objectives
• WG
• Methods
• Work in progress
• Conclusions…………………………………………………………………………………………….slide 22
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 3
Avionics-Power interfaces / PREAMBLEAcronyms• ADHA Advanced Data Handling Architecture
parallel studies (RUAG/ADS, TAS-I)
• DOD Depth of Discharge
• OBDH On-board Data Handling (SubSystem)
• EPS Electrical Power SubSystem
• MBSE Model Based System Engineering
• MPPT Maximum Power Point Tracker
• PCDU Power Conditioning and Distribution Unit
• S3R Sequential Shunt Switching Regulator
• SA Solar Array
• SADE Solar Array Drive Electronics
• SADM Solar Array Drive Mechanism
• SAR Solar Array Regulator
• SOC State of Charge
• SOH State of Health
(Key) definitions• Observability of a system
A system is said to be observable if its current state can be estimated using only the information from its outputs.In other words, one can determine the behaviour of the entire system from the system's outputs.
• Functional/logical viewThe perspective of a system that identifies its functionality without specifying the physical allocation of the relevant functions
• Physical viewThe perspective of a system that identifies its functionality including the physical allocation of the relevant functions
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 4
Electrical Power subsystem – a real view
Solar Array
SADM
SADE
PCDUSecondary DC/DC converters
Battery
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 5
Electrical Power subsystem
Solar Array
SADM
SADE
PCDUSecondary DC/DC converters
Battery
Electrical Power Subsystem (EPS)
Equipment 1
Equipment 2
Equipment n
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 6
o Many variants, according to mission (environment, orbits)
• Different solar arrays
• Different batteries
• Different PCDUs with different internal architectures
– Regulated or unregulated bus
– 28V, 50V, 100V regulated; around 28V or 50V unregulated (but not real standard)
• Different or no SADM/SADE…
• Different distribution lines (for essential, non essential equipment, heater lines, etc)
Electrical Power Subsystem variability
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 7
o It makes sense to be as general as possible…
Power Subsystem Reference Architecture … (to be continued)
`
Element1(E1)
Power line
Signal line
Pyro line
APS.P.a.1.s APS element, Interface P (power), interface type a,interface instance 1, source side s
TMTC.S.b.2.r TMTC element, Interface S (signal), interface type b,interface instance 2, receiver side r
PCDU.PY.g.3.l PCDU element, Interface PY (pyro), interface type g,interface instance 3, load side l
Legenda
Solar Array(SA)
Solar ArrayDrive
Electronics(SADE)
Power Conditioning and Distribution Unit
(PCDU)
PCD
U.P
.b.1
.l
PCDU.PY.a.1.s
SAD
E.P.
b.1.
s
SAD
E.P.
a.1.
l
SA.P
.a.1
.s
PCD
U.P
.a.1
.b
Battery(BATT)
BATT
.P.a
.1.b
PCD
U.P
.d.1
.s
PCDU.PY.a.2.s
PCD
U.P
.d.2
.s
PCDU.S.a.4.b PCDU.S.b.2.t
BATT.S.b.1.t
SADE.S.a.1.b
PCD
U.P
.c.1
.s
Power Subsystem
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 8
Avionics-Power interfaces / MOTIVATION
=> Standardisation effort
• At interface level
• As a first step towards more recurrent products
• With a realistic attitude based on consensus
• Making treasure of previous successful experiences
• With the aim to be MBSE ready!
Solar Array(SA)
Solar ArrayDrive
Electronics(SADE)
Power Conditioning and Distribution Unit
(PCDU)
PCD
U.P
.b.1
.l
PCDU.PY.a.1.s
SAD
E.P.
b.1.
s
SAD
E.P.
a.1.
l
SA.P
.a.1
.s
PCD
U.P
.a.1
.b
Battery(BATT)
BATT
.P.a
.1.b
PCD
U.P
.d.1
.s
PCDU.PY.a.2.s
PCD
U.P
.d.2
.s
PCDU.S.a.4.b PCDU.S.b.2.t
BATT.S.b.1.t
SADE.S.a.1.b
Remote Terminal Unit(RTU)
RTU.S.a.4.b
RTU
.P.d
.2.l
RTU.S.b.2.rRTU.S.b.1.rRTU.S.a.1.b
PYRO1PCDU.PY.a.1.l
PYRO2PCDU.PY.a.2.l
UNIT1
UNIT1.S.a.2.b
PCD
U.P
.c.1
.s
UN
IT1.
P.c.
1.l
UNIT2
UNIT2.S.a.3.b
UN
IT2.
P.d.
1.l
UNIT2.S.c.1.b
RTU.S.a.2.b RTU.S.a.3.b RTU.S.c.1.b
Power Subsystem
SAR3SAR2
Solar Array Regulator 1
(SAR1)
APS3
APS.
P.c.
3.s
Control&Telemetry/telecommand Module*(CTM)
APS2
SAR
.P.f.
1.s
AuxiliaryPower
Supply 1(APS1)
APS.
P.c.
1.s
APS.
P.b.
1.l
APS.
P.a.
1.s
CTM
.P.a
.1.l
CTM.S.b.1.b CTM.S.b.2.b CTM.S.b.3.b
SAR
.P.f.
1.s
SAR
.P.f.
1.s
APS.
P.c.
2.s
CTM.S.a.1.b
CTM
.P.a
.1.l
CTM.S.a.2.b
Input switch/OvercurrentProtection 1
(OCP1) OC
P1.P
.e.1
.s
OC
P1.P
.d1.
l
OCP1.S.a.1.b
CTM.S.a.3.b
CTM
.P.a
.1.l
SAR
1.P.
c.1.
lSA
R1.
P.e.
1.l
Input switch/OvercurrentProtection 2
(OCP1) OC
P2.P
.e.2
.s
OC
P2.P
.d.2
.l
OCP2.S.a.2.b
Input switch/OvercurrentProtection 1
(OCP1) OC
P3.P
.e.3
.s
OC
P3.P
.d.3
.l
OCP3.S.a.3.b
LatchingCurrentLimiter 2(LCL2)LC
L2.P
.f.2.
l
LCL2.S.b.2.b
LCL2
.P.g
.2.s
LatchingCurrentLimiter 3(LCL3)LC
L3.P
.f.3.
l
LCL3.S.b.3.b
LCL3
.P.g
.3.s
To load 1
To load 2
To load 3
FromSolarArray
NOTES
1. For simplicity the PCDU example contain just the Solar Array regulation part and not the battery management one2. * Provided with internal redundancy
LatchingCurrentLimiter 1(LCL1)LC
L1.P
.f.1.
l
LCL1.S.b.1.b
LCL1
.P.g
.1.s
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 9
Avionics-Power interface / SUBJECTS AND OBJECTIVES
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 10
o Gives account of Power Subsystem large variability
o Realistic
• Covering those interfaces that are actually already largely used in applications
• No projection of too idealistic / too theoretical ideas
o Opportunistic
• Covering those (mature) interfaces for which standardization seems possible
• Considering that effective standardization is consensus based
Power Interfaces Standardisation – The approach used so far…
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 11
Power Interfaces Standardisation – key topics
`
Element1(E1)
Power line
Signal line
Pyro line
APS.P.a.1.s APS element, Interface P (power), interface type a,interface instance 1, source side s
TMTC.S.b.2.r TMTC element, Interface S (signal), interface type b,interface instance 2, receiver side r
PCDU.PY.g.3.l PCDU element, Interface PY (pyro), interface type g,interface instance 3, load side l
Legenda
Solar Array(SA)
Solar ArrayDrive
Electronics(SADE)
Power Conditioning and Distribution Unit
(PCDU)
PCD
U.P
.b.1
.l
PCDU.PY.a.1.s
SAD
E.P.
b.1.
s
SAD
E.P.
a.1.
l
SA.P
.a.1
.s
PCD
U.P
.a.1
.b
Battery(BATT)
BATT
.P.a
.1.b
PCD
U.P
.d.1
.s
PCDU.PY.a.2.s
PCD
U.P
.d.2
.s
PCDU.S.a.4.b PCDU.S.b.2.t
BATT.S.b.1.t
SADE.S.a.1.b
PCD
U.P
.c.1
.s
Power Subsystem
Power distribution interfaces (source &
load) based on Latching
Current LimitersECSS-E-
ST&HB-20-20, 2016
Actuators power interfaces
(source and load)ECSS-E-ST&HB-20-
21, 2019
Failure Detection, Isolation and
Recovery
+ Secondary
power distributionTM/TC interfaces
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 12
o Identification and agreement on electrical power subsystem reference architectures
o Cooperation with any standardisation activity concerning back plane definition for avionic equipment (ADHA, other)
Power interfaces and SAVOIR, Prerequisites
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 13
Avionics-Power interfaces / (SAVOIR)WORKING GROUPToR agreed mid March 2020
Participation
ADS, N. Neugnot, J,. Seronie-Vivien
CNES, C. Elisabelair
DLR, N. Aksteiner
ESA, S. Landstroem, O. Mourra, F. Tonicello
OHB, J. Caudepon
RUAG, H. Myllymaki
SENER, C. Tato
TAS, G. Bouhours, J.L. Bolsee
7 Web-meetings performed so far
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 14
Avionics-Power interface / METHODSReference architecture definition!
• Two step approach, functional/logical layer first, physical layer after that
• Most importance given to the precise correspondence of verbal definitions and assumptions with the relevant reference block diagrams
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 15
Avionics-Power interface / METHODSReference architecture definition!
• Two step approach, functional/logical layer first, physical layer after that
• Most importance given to the precise correspondence of verbal definitions and assumptions with the relevant reference block diagrams
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 16
Avionics-Power interface / METHODS / in practice…
1. Broad system/subsystem functional/logical definition => EPS2. Relevant (verbal) functions
functional/logical description (as exhaustive as possible)
Example
Power conditioningis the function of the powersubsystem dedicated to theconversion of power comingfrom power generation, andfrom or to energy storage to thepower bus. The powerconditioning function isregulated by the power controlfunction.
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 17
Avionics-Power interface / METHODS / in practice…
1. Broad system/subsystem functional/logical definition => EPS2. Relevant (verbal) functions
functional/logical description (as exhaustive as possible)
Example
Power conditioningis the function of the powersubsystem dedicated to theconversion of power comingfrom power generation, andfrom or to energy storage to thepower bus. The powerconditioning function isregulated by the power controlfunction.
3. Block diagram (“twin”) functional/logical function description
Example
Power conditioning
Power line Signal line
The arrows indicate the flow of power or of the signal
From/to Energy Storage
From Power Generation
From/to Power Control
From/to Power
Monitor
To Power
Bus
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 18
Avionics-Power interface / METHODS / in practice…
1. Broad system/subsystem functional/logical definition => EPS2. Relevant (verbal) functions
functional/logical description (as exhaustive as possible)
Example
Power conditioningis the function of the powersubsystem dedicated to theconversion of power comingfrom power generation, andfrom or to energy storage to thepower bus. The powerconditioning function isregulated by the power controlfunction.
3. Block diagram (“twin”) functional/logical function description
Example
Power conditioning
Power line Signal line
The arrows indicate the flow of power or of the signal
From/to Energy Storage
From Power Generation
From/to Power Control
From/to Power
Monitor
To Power
Bus
4. Overall Block diagram (“twin”) functional/logical function description
Example
Power generation
Power conditioning
Power control
Power distribution
Power line Signal line
Power monitor
The arrows indicate the flow of power or of the signal
Energy storage Power Bus
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 19
Avionics-Power interface / METHODS / in practice…
1. Broad system/subsystem functional/logical definition => EPS2. Relevant (verbal) functions
functional/logical description (as exhaustive as possible)
Example
Power conditioningis the function of the powersubsystem dedicated to theconversion of power comingfrom power generation, andfrom or to energy storage to thepower bus. The powerconditioning function isregulated by the power controlfunction.
3. Block diagram (“twin”) functional/logical function description
Example
Power conditioning
Power line Signal line
The arrows indicate the flow of power or of the signal
From/to Energy Storage
From Power Generation
From/to Power Control
From/to Power
Monitor
To Power
Bus
4. Overall Block diagram (“twin”) functional/logical function description
Example
Power generation
Power conditioning
Power control
Power distribution
Power line Signal line
Power monitor
The arrows indicate the flow of power or of the signal
Energy storage Power Bus
5. “Get inside the box”, functional/logical function description
Example
Power distribution
Deployment Actuator
Electronics
Platform and payload
equipment distribution
Thermal heater distribution
Power distribution
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 20
PCDU
Avionics-Power interface / METHODS / in practice…
Power generation
Power conditioning
Power control
Power distribution
Power line Signal line
Power monitor
The arrows indicate the flow of power or of the signal
Energy storage Power Bus
From functional/logical to physical block diagram / ”allocation”
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 21
Avionics-Power interface / METHODS / in practice…From functional/logical to physical block diagram / ”allocation”
Power distribution
Power monitor
Power generation
Power conditioning
Power control
Power line Signal line
The arrows indicate the flow of power or of the signal
Energy storage Power Bus
PCDU
Some monitor sub-function is done outsidethe PCDU (e.g. in the OBDH)
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 22
PCDU
Power distribution
Power monitor
Power generation
Power conditioning
Power control
Power line Signal line
The arrows indicate the flow of power or of the signal
Energy storage Power Bus
Avionics-Power interface / METHODS / in practice…From functional/logical to physical block diagram / ”allocation”
Some monitor sub-function is done outsidethe PCDU (e.g. in the OBDH)
Some distributionsub-function is done outside the PCDU (example: in the PPU)
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 23
Avionics-Power interface / METHODS / in practice…Instantiation of physical functions, where interfaces are impacted
SA conditioning
SAR
S3R
SA conditioning
SAR
Converter
MPPT
Power conditioning
From/to Energy Storage
From Power Generation
From/to Power Control
From/to Power
Monitor
To Power
Bus
SA conditioning
Battery charge and discharge
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 24
Avionics-Power interface / WORK IN PROGRESS
• Reaching agreement on
• Functional/logical EPS description, including both nominal and contingency aspects
• The level of depth to go to(see “Get inside the box” , slide 15)
• Possible instantiation options on EPSphysical view
• Starting to identify the observability andcommandability needs of all Primes/LSI and translate this need into standard interfaces where possible and convenient
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 25
Avionics-Power interface / WORK IN PROGRESS / exampleDiscussion on
EPS observable items, as an input for the agreed telemetry set (and the relevant interfaces, according to possible instantiation of the physical layer)
Observable items
Information available for Flight/Ground/AIT purposes
Processing Accuracy
Battery DOD Flight second ±3% of DODBattery SOC Flight second ±5% of SOCBattery SOH Ground month ±3% of SOHBattery internal impedance (DC, AC) Ground hour ±10% of full scaleBattery temperature Ground minute ±2°CSA instantaneaous output power Ground second ±3% of full scaleSA available power (of possible) Ground second ±3% of full scale… … … …… … … …
ESA UNCLASSIFIED - For Official Use Ferdinando Tonicello, TEC-E, Electrical Department | ESA-TEC-HO-020560 | ESTEC | 16/10/2020 | Slide 26
Avionics-Power interface / CONCLUSIONS
Too early to have some definitive conclusions, but…
1. We identified a workable way to have a MBSE ready approach to reference architecture! (see “ METHOD” slides)
2. Whatever the level of interface definition we will achieve, it will be agreed by European Large System Integrators, European Agencies and by some of the most important power equipment manufacturers and users
3. This (interesting) work continues…