UTXvZRP: Differential, distance, overcurrent and earth fault protection
UTXvZRP is a high-speed, current differential and distance protection relay for HV overhead lines and cables, operating with the effectively grounded neutral point.
It provides fast, selective and reliable CB tripping after detection of any kind of PTP (Phase – to – Phase) and PTG (Phase – to – Ground) failure.
Quick and high-precision measurements of any faulted loop impedance together with simultaneous fast finding of distance to the faulted point, all these are the clue of reliable UTXvZRP operation.
The device is equipped with digital A/C converters, standardly with network: protocols – Ethernet and TCP/IP data transfer and serial interfaces (IEC 870 – 5 – 103 protocol), with fibre optic data transfer possibility. CANBus interface (2 channels) for superior system is optional. Moreover, UTXvZRP cooperates with Xserver concentrator, which may have DNP3.0 (Distributed Network Protocol version 3) protocol implementation.
UTXvZRP is a comprehensive distance protection relay comprising 6 (L1–G; L2–G; L3–G; L1–L2; L1–L3; L2–L3) impedance measurement loops.
UTXvZRP Hardware options (available on request)
- ZRP/6 – six analog signals (3 x CT + 3 x VT) inputs (IL1,IL2,IL3,UL1,UL2,UL3)
- ZRP/8 – eight analog signals (4 x CT + 4 x VT) inputs (IL1, IL2, IL3, IE, UL1, UL2,UL3, U4) – available with voltage stages, Active/Reactive Power and Energy measurements, Synchrocheck scheme
- ZRP/8A – eight analog signals (4 x CT + 4 x VT) inputs (IL1, IL2, IL3, IE, UL1, UL2, UL3, U4) – available with voltage stages, Active/Reactive Power and Energy measurements, 1 and 3 phase Auto-reclose and Synchrocheck scheme
- ZRP/8E – eight analog signals (4 x CT + 4 x VT) inputs (IL1, IL2, IL3, IE, UL1, UL2, UL3, U4) – available with voltage stages, Active/Reactive Power and Energy measurements, 1 and 3 pole Auto-reclose and Synchrocheck scheme. Optionally digital antialiasing active current and voltage filters, for a long-distance EHV lines. This solution is especially useful for an unstable waveform suppression, generated at the long-distance EHV lines.
All the options of UTXvZRP device are equipped with phase current-differential stage (balanced via dedicated TRbus communication channel). Fast data transfer is provided between two cooperating relays, installed at the opposite HV line ends each.
- Multiprocessor, functional decision-making and measuring system, equipped with four groups of protection settings,
- Galvanically insulated analog and digital inputs and outputs,
- segmental current differential stage,
- uniform teleprotection interface, with „weak-infeed” power supply logic and „echo” function,
- six-zone, rectangular, under-impedance operational characteristics with independent settings both for: R and X (for phase-to-phase faults with distance reduction of RD and XD characteristics) and RE and XE (for earth faults),
- programmable direction for each zone and programmable angular area of under-impedance protections,
- types of distance stage pick-up: under-impedance (from 6th zone) and/or overcurrent,
- voltage memory for determination of close faults direction,
- handling of parallel circuit for distance protection,
- protection device activation delay times. They can be set independently for phase-to-phase and earth faults in each zone and for each type using additional protective functions (e.g. I>; U<),
- each zone or other protective stages can response to signal (activation report),
- signalling of transformer voltage ration fuses failure,
- protective function of line tripping in case of switch-on-to-fault,
- 1-pole (Z/8A, Z/8E) and/or 3-pole, 4-step, 6-program autoreclosure for any protective or logic function. AR can be picked up internally or externally. Handling of developing faults. 1-pole and/or 3-pole tripping.;
- precise Fault Locator (FL),
- LCD bay terminal screen displaying actual (CB, bus and line reclosers, earthing switches) status,
- possibility to relate each protective function and AR to „link”,
- automatic of line synchronous switch-on and line tripping blocking in case of power swing occurring (power swing detector) – Z/8, Z/8A, Z/8E,
- 3-phase, 2-stage overcurrent-time protection: (I>T and I>>T) with various time characteristics,
- second harmonic phase current compound detector
- thermal model (two stages, option),
- 2-stage, directional earth fault protection (IEk1>T and Iek2>T) with rectangular and cosinusoidal angular characteristics and various time characteristics,
- non-directional earth fault protection with various time characteristics,
- circuit breaker failure protection (CBFP) – programmable current and time conditions,
- handling of external emergency tripping request (tripping with fault report and CBFB handling),
- station signalling functions: BDI, AL, EMT,
- programmable signalling threshold of phase voltages fading,
- constant control of breaker circuits continuity,
- under- and over-voltage stages,
- signalling of currents and voltages unbalance,
- functions of cooperation with the circuit breaker, including its remote control,
- 32 logic functions with programmable modifiers for simple and complex algorithms realization,
- detailed fault tripping report – events and interference recording (4 (3) voltages, 4 (3) currents and 16 digital channels with 1 ms sampling time) with possibility of recorder internal or external pick up; binary inputs ensure chronological recording of protection device operation and trippings,
- time synchronization possibility and analog inputs synchronous sampling function,
- possibility of earth currents values summing, that are switched off by circuit breaker,
- power measurement, energy meters (four-quadrant) – Z/8, Z/8A, Z/8E,
- OC trip counters and device operation times,
- graphic display, 11-key keyboard and 16 LEDs (15 freely programmable),
- measuring values and fault reports display readout and transmission to superior system,
- device internal systems permanent control,
- three password-protected authorization levels,
- possibility of visualization, control and configuration by SAZ 2000 program,
- possibility of cooperation with Automatic Over Ethernet (AoE) systems and Alice`79 system,
- possibility of automation realization between stations using TRBus transmission channel.