One-day Conference 18 March Power Supply, EMC and Signalling, in Railway Systems

Transcription

1 One-day Conference 18 March 2017 Power Supply, EMC and Signalling, in Railway Systems EMC Management and Related Technical Aspects in Railway Systems By Dr Peter S W LEUNG Hong Kong Chapter 1

2 Fixed installation - A particular combination of several types of apparatus, and where applicable, other devices, which are assembled, installed and intended to be used permanently at a predefined location. EMC Directive 2014/30/EU ). Fixed installation/large systems - Large in size, and require system integration. Features : Whole system cannot be EMC tested prior to installation Required to Commit to comply with some EMC particular specifications, code or practice. 2

3 What is the EMC assurance process for Large Systems? EMC is an essential part in the system assurance for a complex project, in providing a top level guidelines for all parties including the contractors, subcontractors and equipment suppliers delivering the railway system to produce a structured evidence of EMC analyses and submissions. How to meet the requirements for EMC assurance? 3

4 Definition of EMC : Function satisfactorily in its electromagnetic environment without introducing intolerable electromagnetic disturbances to other equipment in that environment - EMC Directive 2014/30/EU Often this is also the ultimate goal and objective of EMC management plan or control plan to the assurance process. function satisfactorily and safely The railway environment is considered harsh with respect to Electromagnetic Interference (EMI) 4

5 The EMC Management is commonly based on a systematic approach, taking into account all sources and susceptible equipment, subsystem and systems located internally and externally to the rail environment and where all EMC interactions exists for at different levels : Equipment level EMC type tests Inter-(sub)system level EMC guidelines, Risk analysis Extra-system level third parties, EMC impacts, human safety issues 5

6 EMC Assurance Process relies on major components of: Compliance to EMC standards and guidelines Risk Identification and Risk Analysis for various system integration aspects and for different prospective of an EMC solution EMC Risk Log or safety Hazard Log 6

7 Third Party Systems and Infrastructure Extra PDS ATC Extra Airport Intersubsystem SIG Rectifier Intra Switchgear Intersubsystem Police & Fire Stations Extra Extra Other, future Railways Intra CBTC Axle counter Walkie talkie Intra COMM Tetra TVS Intersubsystem Inverter Intra VEH Capacitor Intersubsystem Extra External EM Environment Railway System Extra 7

8 ESD RS RE Emission CE CS 8

9 9

10 EN Industrial, scientific and medical (ISM) equipment.. EN ITE...Radio disturbance characteristics. Limits and methods of measurement EN ESD immunity test EN Radiated, radio-frequency, electromagnetic field immunity test EN Electrical fast transient/ Burst immunity test EN Surge immunity test EN Immunity to conducted disturbances, induced by radio-frequency fields EN Power frequency magnetic field immunity test EN Voltage dips, short interruptions and voltage variations immunity tests EN Harmonics and inter-harmonics EN : Harmonics Emissions EN : Flickers and voltage fluctuations 10

11 Conducted disturbance (150 khz 30 MHz) Class A and Class B ITE with both Average and Quasi peak limits Mains terminal disturbance Voltage (in dbuv) Common mode disturbance at telecommunication ports Voltage and Current Radiated disturbance (30 MHz 1 GHz) Class A and Class B ITE with Quasi peak limit Enclosure (10m distance) E-field When reading shows fluctuations close to the limits, observed for at least 15s at each measurement frequency Remarks: If average limit is met when using a quasi-peak detector receiver, the EUT shall deemed to meet both limits. Radiated disturbance (1 GHz 6 GHz) Class A and Class B ITE with Peak and Average limits Enclosure (3m distance) E-field When reading shows fluctuations close to the limits, observed for at least 15s at each measurement frequency.

12 150KHz to 30MHz depend on type of device (steps limits at 0.15, 0.5 and 5 MHz) Measurement according to class A/B devices, warning shall be labelled as in Class A

13 80MHz 1GHz EN (RCL environment) 80M-1000MHz, 3V/m 1.4G-2GHz, 3V/m 2G-2.7GHz, 1V/m EN ( Rolling stock -Apparatus) 80M-1000MHz, 20V/m 1.4G-2GHz, 10V/m 2.1G-2.5GHz, 5V/m To all 4 sides..

14 Electrostatic Discharge (ESD) EN Ambient temperature: 15 o C to 35 o C Relative humidity: 30 % to 60 % Atmospheric pressure: 86 kpa to 106 kpa 14

15 Discharge Electrodes of the ESD Generator C = 50 to 250 pf R = 500 to 10k V C = 0 to 30kV ( above 30V will have corona effect ) L = nH First order model, TRIBOELECTRIC EFFECT Threshold of feeling: 2-4kV Everyone can feel: 5kV Memorable event: 15kV Well defined dimensions for the discharge electrodes 15

16 simulating the impact of spark or arcing, commonly from opening/ breaking of a current flowing switch Coupling of the EFT into electronic products occurs when power cables handling high currents are spontaneously varies nearby of power, data, I/O cables.

17 EFT is the immunity requirement on impact from power switches Measurement done on +/- 2KV on line-line or +/- 1KV on Line to earth No degradation of performance (A) is expected to EUT under the influence

18 Surges on the AC power mains is result of switching operations in power grid and from nearby lightning strikes, either directly to power distribution system or nearby ground. Radiated coupling of surges into I/O lines generally occurs when the lines are considerably lengthy (thus proud of induction). Electronic products are tested for Surge immunity to ensure their continued reliable operation under realistic levels of surge voltages. It is essential to demonstrate apparatus used in Railway able to sustain and self recoverable (B) under surge conditions

19 To simulate the impact lightening strike +/- 2KV line-line, +/- 1KV Line-Earth Functions of Railway EUT expected to be self recoverable (B).

20 Disturbance is generated by intentional RF transmitters Cable attached to the EUT are in resonant mode (λ/4, λ/2) CDN to ensure one-directional RF injection into EUT Rail apparatus to 10V/m across 9KHz to 80 MHz

21 ESD EFT Surge Pulse characteristic Sharp rise time Sharp rise time, repeated pulse Relative energy mj mj J Peak voltage 15KV 2KV 2KV Eff. Current range A A KA Sources Static Switching of circuit lighting Slower rise time and declining pulse

22 harmonics is regulated and verified up to 40th harmonics (2KHz).

23 voltage fluctuations - Certain products intermittently take power from mains and causing the supply voltage to dip, resulting potentially supplier instable, lighting to flick. Flicker measures current variation over time (up to 2 hours) and uses statistical techniques to quantify the severity of flicker. Max allowable voltage fluctuation > 4% or 3.3% for disturbance >0.5s

24 magnetic fields at AC mains frequencies, in association with power transformers. Common problems to electronic displays, Hall effect sensors, and other electronic products having a sensitivity to magnetic fields. EUT to sustain H A/m immunity for 50 Hz and 300 A/m for DC (no degradation (A) is allowed)

25 In compliment with Power magnet field, Pulse Magnetic Fields are produced as a result of a large current impulse through a conductor. Example is lightening current flowing through a grounding conductor at a power sub-station. Pulse magnetic fields can also occur in railway system where very large current impulses are used in a power transmission process (Traction substation). Immunity to pulse magnetic field of 300 A/m (self recoverable (B) is expected)

26 Category A - The measured object continues operating normally, unaffected by the interference Category B - The measured object is interfered with, but functions without degradation once the interference has been removed Category C - Loss of function during the test, but functions resume after resetting the measured object Category D - the function was lost permanently

27 Compliance Matrix: Summarizing EMC type test information according to the requirements. Pre-compliance test/ type test information. Provide judgment on discrepancies, and justification on deviation. 27

28 PDS SIG & COMM Apparatus Signalling and Telecomm

29 EN50121 :2015 EN Railway Applications Electromagnetic compatibility, Part 1 General EN Railway Applications EMC, Part 2 Emissions of the whole railway system to the outside world EN Railway Applications Electromagnetic compatibility, Part 3-1: Rolling Stocks EN Railway Applications Electromagnetic compatibility, Part 3-2: Rolling Stocks EN Railway Applications EMC, Part 4 Emission and immunity of the signalling and telecommunication Apparatus EN Railway applications EMC, Part 5 Emission and immunity of fixed power supply installations and apparatus EN EN EMC. Generic standards - Immunity for residential, commercial and light-industrial environments EN EMC Generic Standard Immunity for industrial environments EN EMC - Generic standards. Emission standard for residential, commercial and light-industrial environments EN EMC - Generic Standard Emission standard for industrial environments Others EN Electromagnetic Compatibility (EMC): Part 5 Installation and mitigation guidelines, Section 2 Earthing and cabling EN Railway applications Protective Provisions against Electric Shock EN Protection against lightning(parts 1-4) 29

30 System Level - EN50121 :2015 EN Railway Applications Electromagnetic compatibility, Part 1 General EN Railway Applications EMC, Part 2 Emissions of the whole railway system to the outside world EN Railway Applications Electromagnetic compatibility, Part 3-1: Rolling Stocks EN Railway Applications Electromagnetic compatibility, Part 3-2: Rolling Stocks EN Railway Applications EMC, Part 4 Emission and immunity of the signalling and telecommunication Apparatus EN Railway applications EMC, Part 5 Emission and immunity of fixed power supply installations and apparatus 30