Teleprotection with MPLS Ethernet Communications - Development and Testing of Practical Installations

Transcription

1 Teleprotection with MPL Ethernet Communications - Development and Testing of Practical Installations Tariq Rahman and James Moralez, an Diego Gas & Electric Company olveig Ward and Eric A. Udren, Quanta Technology, LLC Michael Bryson and Kamal Garg, chweitzer Engineering Laboratories, Inc. Presented at CIGRÉ Grid of the Future Conference Cleveland, OH October 23, 2017 lide 1

2 an Diego Gas & Electric ystem an Francisco DG&E Los Angeles ocal Gas an Diego Provides natural gas and electricity to an Diego County and southern Orange County in southwestern California to 3.6 million consumers 1.4 million electric meters and 873,000 natural gas meters in a service area that spans 4,100 square miles Currently, DG&Es teleprotection uses TDM network for teleprotection and CADA The TDM network consist of a mix of direct fiber, T1 multiplexers and TDM ONET, microwave radio, lease-line and channel bank equipment lide 2

3 Introduction Technology evolution is driving towards Ethernet communications - converged utility communications network Typically, packet based IP routing in an Ethernet WAN had been fundamentally less predictable than the deterministic point to point TDM or serial data communications circuit Teleprotection is migrating from ONET to MPL Ethernet To validate the design and in preparation of substation field installations within the DG&E system, laboratory testing was performed using a Real Time Digital imulation or RTD system model Test MPL routers & network configurations were applied to protective relays at the DG&E Integrated Test Facility (ITF) lide 3

4 ONET Characteristics Point-to-point connection Deterministic and low latency (1 3 ms) Equal transmit and receive delay (no asymmetry) Ring redundancy ubstation multiplexer fail-over as low as 2-3 ms Ethernet takes 50 ms Teleprotection Teleprotection lide 5

5 Ethernet IP Characteristics Ethernet is based on IEEE standard with various versions supporting higher data rates and lower latency Widely adopted packet-based technology Non-deterministic latency Basis for IEC P&C Teleprotection Teleprotection lide 6

6 MPL Characteristics MultiProtocol Label witching label field routes Ethernet packets Dynamic and static routing available Predictable latency Pseudowire to support TDM/erial communications Low latency enabled by using a static pre-defined path, and the use of small jitter (data) buffers for teleprotection traffic High priority provisioning through the use of Qo MPL can ensure minimal asymmetry by routing transmit and receive packets over static paths through the same network nodes Fail-over times ms Mitigated by using redundant teleprotection channels in the relay with 0 2 ms fail-over time lide 7

7 DG&E MPL Project Drivers MPL is the current communications transport standard being widely adopted in other IC (Industrial Control ystems) environments such as water, public safety networks, land mobile radio backhaul etc. As MPL is adopted into substation communications (replacing instead of upgrading older technology) it is anticipated that it will deliver significant benefit to overall utility communications providing higher service availability Provide a reduction in maintenance costs (O&M) of a single communication system Provides comprehensive network monitoring and network diagnostics lide 8

8 DG&E Methodology Development of business requirements based on of internal and external drivers Development of in-depth technical requirements Requirements traceability matrix was developed Assuming a successful field trial testing period, the migration of teleprotection will commence as MPL is migrated to substations Created an MPL network lab testing environment Implementation and testing of channel monitoring functions Installation of transmission line field test relays and monitoring for a period of 12 months RTD lab testing of teleprotection over MPL lide 9

9 RTD Model 1 Fault Location C 2 liding Fault Location C 230 kv Circuit Breaker tatic ource L Line hunt Reactor 500 kv C hunt Capacitor 230 kv WTG 5 L Ω 500 kv 34.5 kv Transfer Impedance Branches eries Capacitor PV olar Generation WTG Wind Generation 230 kv 500 kv kv 7 C 34.5 kv WTG 1 to 99% Ω Y Y Δ WTG Tap j33.7 C C L Ω 69 kv 500 kv 500 kv L 500 kv L L 230 kv EQ Transfer Transfer PV PV lide 10

10 Test Requirements and Test etup 1. Latency < 5 ms 2. Asymmetry < 2 ms 3. Failover < 3 ms 4. Availability > 99.95% MPL Typical Testing Network Relay 1 87L CH X 87L CH Y MBA MBB 87L CH X MPL Router A MPL Router B 87L CH Y Relay 1 Primary Path MBA MBB Relay 2 87L CH 2 MBA MBB Router Failover Path MPL Network Router Failover Path 87L CH 2 MBA MBB Relay 2 Relay 3 87L CH 2 MPL Router C econdary Path MPL Router D 87L CH 2 Relay 3 lide 11

11 Asymmetry <2 ms - Test etup 2 ms asymmetry introduced 87L Channel Asymmetry Test etup Relay 1 87L CH X MPL Router MPL Router Relay 1 87L Forward Path 87L CH X Relay 2 Relay 2 Relay 3 Asymmetry Delay (Linux Desktop) 87L Return Path Relay 3 lide 13

12 Fail-over <3 ms Test etup 87L Channel Link Break Test etup Relay 1 87L CH X 87L CH Y MPL Router MPL Router Relay 1 Primary Path Ethernet Link Breaker 87L CH X 87L CH Y Relay 2 87L CH 2 Router Failover Path Router Failover Path 87L CH 2 Relay 2 Relay 3 87L CH 2 Ethernet Radio econdary Path Ethernet Radio 87L CH 2 Relay 3 lide 14

13 Latency <5 ms Latency is measured from (a)-(a) or (b)-(b) depending on the relay type lide 15

14 Latency <5ms - Test Results lide 16

15 ummary of Test Results Communication Requirement pecification Results Latency < 5 ms Pass 1 Asymmetry < 2 ms Pass 2 Failover < 3 ms Pass 3 Availability > 99.95% N/A 1 Latency < 5 ms achieved with specific Jitter Buffer and Payload MPL router settings. 2 Asymmetry < 2 ms achievable with specific network design. Laboratory tests show protection operates correctly at 2 ms asymmetry specification limit. 3 Failover < 3 ms achievable with 2 of 3 relays meeting specification. Protection system with designed failover paths and protective relay failover meets failover specification. MPL routers do not meet failover specification failing over to backup Ethernet router path. lide 17

16 Conclusions It is not possible to fully emulate all of the production MPL network conditions within a lab environment, but it does provide the ability to create baseline results. To ensure that any issues that may arise during the field test period are related to the communications network, and are not due to a protection scheme deficiency, the schemes and relay settings are thoroughly tested in the RTD lab on a model that accurately simulates the circuit to be protected. Root-cause analysis of any protection misoperations during field testing will not need to involve extensive protection scheme retesting as the schemes and settings have been fully verified prior to the field relay test. lide 18

17 Conclusions (cont.) Laboratory and field relay testing will help to validate the new MPL communications system and to promote learning about the new communications system for DG&E engineers, technicians and operations personnel. Laboratory testing of the new MPL communications system using the RTD has allowed many real-world types of tests. The comparatively long failover times for MPL channels (>50 ms) were avoided by using redundant relay channel connections and MPL router paths. Direct fiber paths do not need to be converted to MPL. lide 19

18 Conclusions (cont.) Laboratory testing has shown that MPL networks are a viable communications medium for protective relay telecommunication traffic if designed to account for latency, asymmetry, failover and availability. RTD tests validated settings that will go into the routers and switches of the MPL network. RTD testing has allowed DG&E to specify and set the channel/communications monitoring parameters in the relays to support a packet based network, which was not necessary with a TDM network. lide 20

19 Acknowledgements A special Thank You to those who have contributed to the creation and completion of this paper and presentation: Mike Mahoney Burns & McDonnell Clint truth and Cory truth CI Networks Terry Wright GDC Consulting lide 21