FPGA properties and safety assurance of NPP I

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FPGA properties and safety assurance of NPP IC
systems
Vyacheslav Kharchenko, Ievgenii Bakhmach,
Alexander Siora RPC Radiy, Ukraine
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Contents
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Contents
4
Introduction
5
Introduction

• Substantial increase of applying of the
  technologies based on programmable logic (Field
  Programmable Gates Arrays FPGA, Application
  Specified Integrated Circuits ASIC) during
  last 10 years (30-40 of general volume).
• Military aircraft control systems (APACHE, B-1B,
  F-16, etc), civil aircraft control systems
  (Boeing 737, Boeing 777, AN-70, AN-140)
• Space control systems (satellites FedSat, WIRE
  the Mars-vehicle Spirit).
• Application of FPGAs in NPP ICs (Ukraine
  and Russia 1999-start, 2002 1000, 2006 6000,
  2007 more than 8000 chips)
• Development of CAD-means and languages (from VHDL
  to JHDL)

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Introduction
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7
Introduction
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Introduction

• A. Avizienis et al. Basic Concepts and Taxonomy
  of Dependable and Secure Computing // IEEE
  Transactions on Dependable and Secure Computing,
  vol. 1, ? 1, 2004. - P. 11-33.
• Yastrebenetsky M.A. (edit.) NPP ICs Problems
  of Safety. ?. ??chnique, 2004. 472 p.
• Kharchenko V.S., Sklyar V.V. (edits). FPGA-based
  NPP Instrumentation and Control Systems
  Development and Safety Assessment. RPC
  Radiy, National Aerospace University named
  after N.E. Zhukovsky KhAI, State Scientific
  Technical Center on Nuclear and Radiation Safety,
  2008. - 188 p.

• An analysis of
• FPGA-technology features in context of NPP IC
  systems safety assurance
• Methods and examples of increasing
  dependability and safety of FPGA-based NPP IC
  systems

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2. FPGA-projects development safety context
2.1. Technologies of FPGA-projects development
1. Development of graphic diagram using the
library blocks in computer aided design (CAD)
environment. 2. Development of (simple) software
models using special hardware describing
languages
3. Development of program code for operation in
environment of microprocessor emulators which
are implemented in FPGA as Intellectual
Properties Cores.
IIP (Infrastructures of IPs)
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2. FPGA-projects development safety context
2.2. Features of FPGAs (1) Sequential data
processing in SW-based system
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2. FPGA-projects development safety context
Features of FPGAs (2) Parallel data processing
in FPGA-based system
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Features of FPGAs
Simplification of development and verification
processes

• apparatus parallelism in control algorithms
  execution and realization of different functions
  by different FPGA elements
• absence of cyclic structures in FPGA
  projects
• identity of FPGA project presentation in
  respect to initial data
• advanced test-bed for FPGAs
• verified libraries and IP-cores in FPGA
  development tools.

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Features of FPGAs
2.3. Ways of FPGA-technologies applying for
development of IC platform RADIY
A. Functions presented as technological
algorithms for control of reactor equipment are
realized in the form of graphic diagrams.
Examples of such functions
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Features of FPGAs
2.3. Ways of FPGA-technologies applying for
development of IC platform RADIY
B. Hardware describing languages are used as an
addition to graphic diagrams For example, to
describe complicated calculations. C. Auxiliary
functions are realized in the form of program
code in environment of microprocessor emulators.
Examples of such functions
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Features of FPGAs
An example of FPGA-based functional unit of IC
platform Radiy
Three technologies of FPGA-projects development
can be combined in the one unit
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3. Risk analysis of FPGA-based IC systems
3.1. Risk analysis model

• Risk analysis model and related terminology are
  described in the standards of IEC 61518 series
  Functional safety of electrical/electronic/progra
  mmable electronic safety-related systems.

• Main properties of IC systems are safety
  functions (SF) and safety integrity (SI).
• SF is a function realized by IC system to
  achieve reactor safe state or support against
  dangerous event.
• SI is a probability of SF of IC system
  execution upon all defined conditions within
  defined time.

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3. Risk analysis of FPGA-based IC systems
Approach for using of common risk analysis model
Common risk analysis model is detailed for
FPGA-based IC systems. Comparative analysis
results of software-based and FPGA-based IC
systems
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3. Risk analysis of FPGA-based IC systems
3.2. Comparative analysis results of
software-based and FPGA-based IC systems (1)
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3. Risk analysis of FPGA-based IC systems
3.2. Comparative analysis results of
software-based and FPGA-based IC systems (2)
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3. Risk analysis of FPGA-based IC systems
3.2. Comparative analysis results of
software-based and FPGA-based IC systems (3)
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3. Risk analysis of FPGA-based IC systems
Results of an comparative risks analysis of
software-based and FPGA-based IC platforms

• Risks of software application are more for 10
  from 16 general requirements.
• Risks of software and FPGA application are equal
  for 6 from 16 general requirements.
• Specific risks of FPGAs application do not
  exceed specific software risks.
• Specific risks of FPGAs application are disarmed
  by use of standard and special means.
• Hence application of FPGAs allows
• to simplify IC systems structure, development
  and verification processes
• to reduce software volume
• to reduce software failures probability and
  probability of common cause failures.
• Conclusion application of FPGAs permits to
  increase IC system safety.

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4. Safety assurance of FPGA-based IC systems
4.1 Peculiarities of FPGA-technologies and
dependability assurance possibilities in
FPGA-based systems (1)

• A. Simplification of development and verification
  processes (see above)
• apparatus parallelism
• absence of cyclic structures
• identity of FPGA-project presentation to initial
  data
• advanced test-bed in FPGA development tools
• verified libraries and IP-cores.
• B. Assurance of fault-tolerance, data validation
  and maintainability
• possibilities of redundancy for intra-crystal and
  inter-crystal levels
• possibilities of diversity and multi-diversity
  implementation
• possibilities of reconfiguration and recovery in
  the case of components failures
• possibilities of enlarged technical diagnostic.

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4. Safety assurance of FPGA-based IC systems
4.1 Peculiarities of FPGA-technologies and
dependability assurance possibilities in
FPGA-based systems (2)

• C. Security assurance
• FPGA reprogramming is possible only with use of
  special equipment.
• D. Stability and survivability assurance
• tolerance to external impacts (electromagnetic,
  climatic, radiation)
• possibilities of implementing controlled
  multi-level degradation with different
  types of adaptation.

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4. Safety assurance of FPGA-based IC systems
4.2. Fault-tolerance through intra-crystal
network redundancy FPGA-project level
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4. Safety assurance of FPGA-based IC systems
4.3. Diversity in FPGA-based ICs
Evolution of diversity principle low negation
of negation (1)
1) 1980s transition from hardware-based systems
with identical subsystems to systems with
hardware primary subsystem and microprocessor-base
d (software-based) secondary subsystem2) 1990s
use of software-based primary and secondary
subsystems with software diversity (negation
1)3a) 2000s (first half) transaction to
FPGA-based primary and secondary subsystems with
equipment, design and software diversity
(negation 2 - negation of negation)3b) 2000s
(second half) application of FPGA
IP/soft/processor-technologies for primary and
secondary subsystems development using
additionally IP (architecture)-diversity,
conceptual diversity (use of genetic
algorithms,) (next negation)4) next step - ?
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4. Safety assurance of FPGA-based IC systems
4.3. Diversity in FPGA-based ICs
Evolution of diversity principle low negation
of negation (2)
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4. Safety assurance of FPGA-based IC systems
Kinds of diversity in FPGA-based ICs
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4. Safety assurance of FPGA-based IC systems
Multi-diversion systems
W? X, F, U, V, R, ?, Z,
X, U input and output signals F set of
functions V e (two) elemental set of
versions (v1, v2, output signals U1,U2)
Z function of processing version results
(mapping U1,U2 into U) R set of version
redundancy types, vj?V is defined on set
R by use mapping ?.
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4. Safety assurance of FPGA-based IC systems
Automaton model of multi-version FPGA-based
ICs
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4. Safety assurance of FPGA-based IC systems
Diversity implementation in reactor trip system
based on FPGA-platform Radiy

• Equipment diversity
• different electronic components
• different programmable components (FPGAs and
  microcontrollers)
• different circuits of units
• Software diversity
• different programming languages
• different tools for development and verification
• Life cycle (human) diversity
• different teams of designers

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Conclusion

• 1. Implementation of FPGA in NPP IC and other
  critical industries has representative character,
  i.e. there are thousands of FPGA implementations
  in tens of IC systems which are operated during
  several years already.
• 2. FPGA-projects circuits are equivalent to
  technological algorithms of signal forming of NPP
  actuators control. Thus, as distinct from
  software development project, for FPGA-projects
  during the transition from one development stage
  to another the basic information for development
  changes slightly that decreases risks of its
  distortion and risk of defects addition.
• 3. FPGA is unique technology that allows
• to realize multi-reconfiguration (programming,
  dynamical function- and dependability-oriented
  architecturing, multi-parametrical
  space-structural adaptation, etc.)
• to propose scalable dependable decisions for
  safety-critical systems
• to develop multi-version systems with different
  product-process version redundancy.

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Conclusion

• 4. Analysis of operation results allows to make a
  conclusion that realization of protection,
  blocking-outs, control and regulation functions
  based on FPGA is the most effective instrument
  for NPP IC designing which corresponds to the
  requirements of regulative and technical
  documents on safety.
• 5. FPGA-platform Radiy is the basis for
  development and realization of safety and
  scalable decisions for safety-critical IC
  systems.
• In this platform is provided the following
• scalability of system functions types, volume and
  peculiarities (by changing quantity and quality
  of sensors, actuators, input/output signals and
  control algorithms)
• scalability of dependability (safety integrity)
  (by changing a number of redundant channel,
  tiers, diagnostic and reconfiguration
  procedures)
• scalability of diversity (by changing types,
  depth and method of diversity choice).

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Presentation of the book
Kharchenko V.S., Sklyar V.V. (edits). FPGA-based
NPP IC Systems Development and Safety
Assessment / Bakhmach E.S., Herasimenko A.D.,
Golovyr V.A., Kharchenko V.S., Rozen Yu.V.,
Siora A.A., Sklyar V.V., Tokarev V.I.,
Vinogradskaya S.V., Yastrebenetsky M.A. Research
and Production Corporation Radiy, National
Aerospace University named after N.E. Zhukovsky
KhAI, State Scientific Technical Center on
Nuclear and Radiation Safety, 2008. - 188 p.
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Content ?f the book
INTRODUCTION PART 1 PROBLEMS OF FPGA-BASED IC
SYSTEMS DEPENDABILITY AND SAFETY Chapter 1
Dependability and safety of IC systems Chapter 2
FPGA-based IC systems development PART 2
SAFETY ASSESSMENT AND ASSURANCE OF FPGA-BASED NPP
IC SYSTEMS Chapter 3 Risk-oriented assessment of
IC systems safety Chapter 4 Multi-version
technologies of reliability and safety ensuring
for FPGA-based IC systems PART 3 IMPLEMENTATION
OF FPGA-BASED NPP IC SYSTEMS Chapter 5
Construction principles of NPP IC
systems developed by RPC Radiy Chapter 6
Peculiarities of NPP IC systems developed by RPC
Radiy CONCLUSION REFERENCES
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Thank for your attention!
Company Radiy 29 Geroy?v Stalingrada
street, Kirovograd, Ukraine Tel. [phone]
30 20 Fax [phone] E-Mail
marketing_at_radiy.kr.ua
http//www.radiy.kr.ua