NTG MULTIFUNCTON GENERATOR PROTECTION RELAY. NTG-Slide

Transcription

1 NTG MULTIFUNCTON GENERATOR PROTECTION RELAY 1

2 NTG Digital protection relay that integrates a number of functions required r for the protection of generators. It is used in power stations from gas, steam, hydraulic turbine, or diesel driven generators, operating in parallel with the public network and/or in island and with any neutral state and network layout. 2

3 EMERGENCY GENERATORS powered by diesel motors or small gas turbines 100 kva 2 MVA, in BT e MT DISPERSED GENERATORS powered by diesel motors or small gas turbines, wind, solar Industial plants 1 MVA 10MVA, in MT COGENERATION Cogeneration power plants (Gas&oil, chemical..) 1 MVA a 50 MVA, in MT POWER STATION Powered by Hidro, Gas, Steam, Gas turbines from 10 MVA to several hundreds MVA Applications 3

4 A B C D E F G H I A B C D E 19 rack (h=3u, p=300 mm) Power supply LED 8 free assignable LEDs 8 free assignable LEDs (optional) RS232 local communication interface MMI F DSP and CPU LEDs G H I 1 LED (ON service) + 7 free assignable LEDs LCD display keyboard Front view 4

5 A B C-D E F G-H L-M N A Current inputs I/O with connectorized terminals B C-D E F G-H L-M N R Voltage inputs RTD inputs (optional) 8 binary inputs 8 binary inputs (optional) 8 output relays (optional) 8 output relays Power supply Remote interface RS485+RJ45 or Fiber optic (MODBUS TCP/IP) R T T earth terminal Rear view 5

6 A B C C D D G L A Power supply module B Rotor earth fault module C 8 output relays module D 8 binary inputs + 8 LEDs module E PT100 module F CPU module G DSP module E F H H CT/VT module L Communication module Layout 6

7 COMMUNICATION INTERFACE local (RS232) remote RS485 + Ethernet (F.O./RJ45) control& communication (2Mbyte) (8Mbyte) MEASURING INPUTS 40MHz DSP SPI SERIAL BUS 66 MHz CPU FLASH SDRAM 3 phase currents 1 residual current 3 phase voltages 1 residual voltage 1 rotor earth fault 16 channels 10 bit ADC measure&protection (DFT 16 samples/period) thybus PARALLEL BUS I/O MMI Hardware structure 7

8 Selection table 8

9 3 IL (hw setting 1A-5A) IE (hw setting 1A-5A) 3 UL (UN sw programmable) UE (UEN sw programmable) 8 output relays (optional) 8 output relays 8 binary inputs 8 binary inputs (optional) UAUX on request: Vac/dc 24 Vac/dc 230 Vac (DAC200) 8 Inputs PT100 (optional) 64 Earth fault (optional) 16 LEDs 8 LEDs (optional) RS485 Port RJ45 Ethernet Port (optional) Optical Ethernet Port (optional) RS232 port Keyboard Input/Output 9

10 21-51V Underimpedance (21) or voltage-controlled overcurrent protection (51V) coordination with distance protective devices X t t< R t<< Z<< Z< Z G MT AT Z< Z<< Protection elements 10

11 21-51V Underimpedance (21) or voltage-controlled overcurrent protection (51V) Overcurrent protections coordination G MT MT 51V voltage controlled 51V element G MT V voltage restrained 51V element U U a) Generator with step up transformer b) Directly connected generator Protection elements 11

12 24 Overflux V/Hz 26 Thermal Protection with RTD s probes (PT100) Generator limits bearings Stator windings IEC A-B-C t transformer limits shaft TUR GEN rotor stator TR PT (up to 8 RTD probes) 1 alarm pickup + 1 trip for each probe: U/f t q Protection elements 12

13 t 27 Undervoltage U t 59 Overvoltage U t 46 Negative sequence overcurrent Generator limit I 2 2 t=k I2 Protection elements 13

14 27H 59H 100% Stator earth fault protection with 3 harmonic No earth faults 100% 0% measurement on star point G 27H third harmonic Voltage level 27H 59N measurement from broken delta VT 59H Earth faults at the star point 100% 0% G 59N 59H Earth faults at the terminals 100% 0% 100% 0% 90% 70% 27H-59H N 59N (stator earth fault 90%) T Protection elements 14

15 32 Active directional overpower Q 32R 37P 32 P 32 R Active reverse power 37 P Active underpower Faults in prime mover Sequential tripping logic Sequential tripping logic Load shedding Network separation Protection elements 15

16 40 Loss of field A first threshold (fast) X Loss of field with heavy load initial condition B second threshold (delayed) R Loss of field with light load initial condition C alarm A Loss of field with low load initial condition B C Protection elements 16

17 49 Thermal image 50/51 Overcurrent t I 2 t=cost IEC A-B-C I 2 t=cost 50G/51G 87N Earth fault (50G/51G) or restricted earth fault (87N) (90% stator earth fault) 59N Neutral overvoltage (90% stator stator earth fault) I 64F Rotor earth fault Inadvertent energization Protection elements 17

18 50+27 Inadvertent energization IL1 I> IL2 I> 1 IL3 I> 1. VT at GEN side & TRIP UL1 U< UL2 U< & & & 2. VT at GRID side 1 t1 UL3 U< 2 t2 TRIP 74TV CB OPEN 1 Protection elements 18

19 81> Overfrequency 81< Underfrequency Coordination example between four stage pickups underfrequency protection and turbine limits (Load Shedding) grid t Cut load C4 (10 MW) Q 50 MW Forbidden area ( turbine demage) Cut load C3 (30 MW) 130 MW Cut load C2 (40 MW) Cut load C1 (50 MW) 80 MW 81< fn f G T C1 C2 C3 C4 50 MW 40 MW 30 MW 10 MW Q open: C1+C2+C3+C4 (130MW) powered by G (80MW) Protection elements 19

20 BF Breaker Failure IL1 I> IL2 I> IL3 I> IE IE> 1 A. CT at line side B. CT at star side CB CLOSED B TRIP INTERNAL PROTECTIONS TRIP EXTERNAL PROTECTIONS 1 1 A & tbf TRIP BF BF BLOCK NOTA: with CTs at the line side, the current measures and the CB status make reliable the breaker failure function even if the currents are not present (ie. trip 32R, 24, 27, 59) or when an auxiliary contacts discrepancy is detected (52a and 52b). Protection elements 20

21 74VT VT monitoring Fail of the voltage transformer and secondary connections are detected Alarm and block of protective elements affected by loss of voltage (21-51V, 40, 27, 50+27, 37P) Following measuring are employed: three phase currents three phase voltages CB state 74CT CT monitoring Fail of the current transformer and secondary connections are detected Alarm and block of protective elements affected by loss of current (37P, 46, ). Following parameters are employed: residual current residual voltage CT/VT monitoring 21

22 MMI Within the Hz range, NTG change the sampling frequency to keep 16 samples per cycle I, U fn=50 Hz t I, U fn=20 Hz t Measuring accuracy is assured during the start and stop of the generator I, U fn=80 Hz t Frequency tracking 22

23 MMI 8 binary inputs (standard) + 8 binary inputs (optional), freely assignable with the following preset: Ext reset Two profile switching (BANK A, BANK B) synchronization Logic selectivity Logic block of protection functions Trip Circuit Supervision 74CTS CB monitoring (operations, SI, SI 2 t, trip time) Breaker failure (BF) BF Thermal image reset Reset counters Reset CB diagnostic, (SI, SI 2 t, trip time) Reset timer 46 Sequential tripping Binary input allocations 23

24 MMI SEQUENTIAL TRIPPING It is a stop procedure, planned or following delayed trip command, intended to avoid overspeeding TRIP 32R (P->>) TRIP 37P TURBINE VALVE CLOSED & MAIN AND FIELD CB OPEN STEAM T VALVE G CB P The circuit breakers must be open after the turbine valve has been closed, When the power of the residual steam has been exhausted (and the active power is absorbed to drag the turbine). Binary input allocations 24

25 MMI 8 output relays (normal) + 8 output relays (optional) with one change-over contact. The function of each relay is programmable with a matrix structure Max flexibility for setting of the tripping ways FUEL T C B A VALVE Example 1 G talarm FUEL T Example 2 C B A VALE G talarm Operator command Type Function A 87N A 27H B 46 B 51V B 32R B 40 B 27 C 26 C 64F SEQ TRIP. SEQ. TRIP A B C very urgent protections little urgent protections not urgent protections Output relays allocation 25

26 Low power diesel emergency generator (< 1 MVA) transformer-generator parallel grid connect (> 1 MVA, < 10 MVA) Diesel G 81> 49 81< 50/51 51G BASIC T G 32R V 59N 81< > 81< BASIC Application examples 26

27 MMI Parallel generators on the same bus (>10 MVA) Transformer-generator (>10 MVA) G G P 32R V 64F 87N 59N 81< PRO > 81< VT 74CT BF G 59H 59N 26 32R F 27H 59N 81< alternative PRO > 81< 24 74VT 74CT BF Application examples 27

28 Setting & monitoring sw Display, modify and print of settings Event recorder reading and print Parameters reading and store Logical states visualization Off-line setting files Download and upload Reset commands User friendly RS232 (RJ10) PC ThySetter 28

29 MMI Read Frequency f Phase currents IL1, IL2, IL3 (RMS) Residual current IE (RMS) Negative and positive sequence currents I1, I2 Thermal image Dq Phase voltages UL1, UL2, UL3, line-to line voltages U12, U23, U31 (RMS), negative sequence voltage U2 Residual voltage UE Third harmonic residual voltage UE3H Real and reactive power (RMS) Apparent Power Phase power factor Impedance Z, resistance R and reactance X (40) Z power factor cosfz Insulation Resistance (64F) Temperature through thermal probesrtd1 8 Trip counters, start, blocks, CB operations, SI, SI 2 t Binary inputs state DIG-IN Output relays state K1...K16 Logical block state Logic selectivity I/O state Element state ThySetter 29

30 MMI Event recorder date, time cause frequency phase currents IL1,IL2,IL3 residual current IE phase voltage UL1,UL2,UL3 residual voltage UE third harmonic component of residual voltage UE3H total active power P flux insulation resistance (64F) temperature pt100 impedance Z (40) Z resistive component R Z reactive component X Z power factor cosfz binary inputs state DIG-IN output relays state K1...K16 ThySetter 30

31 MMI Ethernet connections with Modbus TCP/IP protocol Communication 31

32 MMI Modbus TCP/IP features Modbus protocol implementation on Ethernet networks same protocol and available for a lot of devices baud rate increase from 19.2 kbps to 10 or 100 MBps mixed systems can be built with TCP/IP and RS485 devices by means of gateways multimaster networks unlimited Ethernet network (Internet) the Modbus TCP/IP protocol make use of Modbus messages for the application layer and the TCP/IP protocols for the Ethernet transfers the NTG is a generic element of the network equipped with an IP address like a common PC Modbus TCP/IP 32