Main Functions

10 36 START: tI>> Fig. 4

Setting for the operate delay of overcurrent starting.

10 50 START: Xfw Fig. 12

Setting for the reactance limit of underimpedance starting.

10 51 START: Rfw P-G Fig. 12

Setting for the resistance limit of

underimpedance starting for phase-to-ground loops.

10 52 START: Rfw P-P Fig. 12

Setting for the resistance limit of

underimpedance starting for phase-to-phase loops.

10 53 START: Zbw/Zfw Fig. 12

Setting for the limit of underimpedance starting in the backward direction.

10 54 START: I>> Fig. 4

Setting for the threshold operate value for overcurrent starting.

10 55 START: IN> Fig. 5

Setting for the threshold operate value of the ground current stage for ground starting.

10 56 START: VN-G> Fig. 5

Setting for the threshold operate value of the voltage trigger V_N-G> for ground starting. If the nominal voltage of the station transformer differs from 100 V, the setting must always be referred to the nominal voltage of the PD 521

In systems with isolated/resonant neutral- point grounding, the operate delay tIN> should be set so that the ground currents I_N that flow as the result of phase-to-ground capacitance reversals do not lead to erroneous ground starting.

Note: Starting does not occur in the case of ungrounded single-phase faults until tIN> has elapsed.tIN> should never be set less than 20 ms so that starting

transfer will not anticipate starting in another phase.

10 60 START: Trip tVN-G>> Fig. 7

Using this setting it is possible to specify whether, for operation of the

S T A R T : V N - G > > trigger, a trip command shall be issued after the

S T A R T : t V N - G > > timer stage has elapsed.

Note: A trip command is issued only if

MAIN: Neutral-point treat. is set to Low-impedance grounding.

10 61 START: tVN-G>> Fig. 5

The operate delay time setting for the S T A R T : V N - G > > trigger.

10 62 START: VN-G>> Fig. 5

Setting for the threshold operate value of the V_N-G>> trigger for ground starting. If the nominal voltage of the station transformer differs from 100 V, the setting must always be referred to the nominal voltage of the

PD 521 (see type identification label) and not to the nominal voltage of the station

transformer.

10 63 START: >>>> Fig. 12

Angle setting for load masking during underimpedance starting.

10 67 START: Operating mode Fig. 9

Operating mode setting for underimpedance and undervoltage starting. The following settings are possible:

o Without V< starting.

Undervoltage starting is deactivated.

o With V< starting, P-G.

Undervoltage starting evaluate decisions of phase-to-ground loops only.

o With V< start. P-G, P-P.

Undervoltage starting measurement systems are switched by ground starting from phase-to-phase to phase-to-ground systems.

10 68 START: I> (Imin) Fig. 8

Base current setting above which under- voltage and underimpedance starting is enabled.

10 69 START: V< Fig. 9

Threshold operate value setting for undervoltage starting.

Note:

The undervoltage fault detection logic can be disabled with the setting “0“. This is

permitted only if a starting by the overcurrent fault detection logic is assured for near faults (Vsh < 2% Vnom).

25 93 START: Z evaluation Fig. 12

This setting determines whether the PD 521 will carry out the impedance calculation of the phase-to-ground loops using the phase current corrected by the set ground factor or using twice the phase current.

12 00 DIST: Zone 4 Fig. 28

Zone 4 can be used as a special zone. This setting determines the way in which zone 4 will be utilized. The following settings are possible:

o Normal

A directional and timer stage is assigned to each impedance zone.

o Section cable - line

With this setting the impedance setting of impedance zone 4 is assigned to timer stage t1 and directional setting N1. The settings t4 and N4 are inactive. If a trip occurs in impedance zones 1 and 4 after t1 has elapsed, an external ARC can be blocked.

o Section line - cable

With this setting the impedance setting of impedance zone 4 is assigned to timer stage t1 and directional setting N1. The settings t4 and N4 are inactive. If a tripoccurs in impedance zone 1 only, after t1 has elapsed, an external ARC can be blocked.

12 01 DIST: X1 (polygon) Fig. 23

12 02 DIST: X2 (polygon) Fig. 22

12 03 DIST: X3 (polygon) Fig. 22

12 04 DIST: X4 (polygon) Fig. 22

Reactance limit setting for impedance zones 1 to 4 in secondary values.

Note: Zone 4 can be used as a special zone (see D I S T : Z o n e 4 setting). This must be taken into account when setting X4.

12 05 DIST: R1 P-G (polygon) Fig. 23

12 07 DIST: R2 P-G (polygon) Fig. 22

12 09 DIST: R3 P-G (polygon) Fig. 22

12 11 DIST: R4 P-G (polygon) Fig. 22

Resistance limit setting for impedance zones 1 to 4 in secondary values for the phase-to- ground loops.

Note: Zone 4 can be used as a special zone (see D I S T : Z o n e 4

12 06 DIST: R1 P-P (polygon) Fig. 23

12 08 DIST: R2 P-P (polygon) Fig. 22

12 10 DIST: R3 P-P (polygon) Fig. 22

12 12 DIST: R4 P-P (polygon) Fig. 22

Resistance limit setting for impedance zones 1 to 4 in secondary values for the phase-to- phase loops.

Note: Zone 4 can be used as a special zone (see D I S T : Z o n e 4 setting). This must be taken into account when setting R4.

12 13 DIST: === (polygon)= Fig. 22

The inclination of the trip polygon in the R direction for the polygonal impedance

characteristic is determined using this setting.

12 23 DIST: Direction N1 Fig. 28

12 24 DIST: Direction N2 Fig. 28

12 25 DIST: Direction N3 Fig. 28

12 26 DIST: Direction N4 Fig. 28

12 27 DIST: Direction N5 Fig. 28

The directional setting specifies in what direction the respective impedance stage measures – referred to the basic measuring direction determined by the connection direction of the measuring circuits and setting 10 04. The following settings are possible:

o Forward directional o Backward directional o Non-directional 12 28 DIST: t1 Fig. 28 12 29 DIST: t2 Fig. 28 12 30 DIST: t3 Fig. 28 12 31 DIST: t4 Fig. 28 12 32 DIST: t5 Fig. 28 12 33 DIST: t6 Fig. 28

Settings for the impedance zone stage times and the backup times.

Note: Zone 4 can be used as a special zone (see D I S T : Z o n e 4 setting). This must be taken into account when setting t4.

If the PD 521 is operating with protective signaling or auto- reclosing control, timer stage t1 is

12 34 DIST: kze P-G HSR Fig. 23

12 35 DIST: kze P-P HSR Fig. 23

The zone extension factors k_ze HSR can be set separately for phase-to-ground and for phase-to-phase loops. When the polygon characteristic has been selected, the zone extension factor setting changes the reactance and resistance limits for

impedance zone 1. The following applies to the measurement:

X1,ze HSR = (kze HSR) × X1

R1,ze HSR = (kze HSR) × R1

X1,ze HSR: reactance changed by the

zone extension factor. R1,ze HSR: resistance changed by the

zone extension factor. When the circular characteristic has been selected, the The following applies to the measurement:

Z1,ze HSR = (kze HSR) × Z1

Z1,ze HSR: impedance changed by the

zone extension factor. Zone extension is controlled by the following functions:

o Protective signaling

o Switch on to fault protection

o An appropriately configured binary signal input.

12 36 DIST: kG angle Fig. 2

Angle setting for the complex ground factor k_G. k Z Z 3 Z G 0 pos pos = - × Z₀: zero-sequence impedance

Z_pos: positive-sequence impedance

k angle arc tanX X

R R arc tan X R G 0 pos 0 pos pos pos = - - -

R₀: zero-sequence impedance resistance R_pos: positive-sequ. impedance resistance X₀: zero-sequence impedance reactance Xpos: positive-sequ. impedance reactance If the calculated value cannot be set exactly, then the next smaller value should be set.

12 37 DIST: kG abs. value Fig. 2

Setting the absolute value for the complex ground factor k_G. k Z Z 3 Z 0 pos pos G = - × Z₀: zero-sequence impedance Z_pos: positive-sequence impedance



 



k X X R R R X G pos pos pos pos = - + - × + 0 2 0 2 2 2 3

R0: zero-sequ. impedance resistance

Rpos: positive-sequ. impedance resistance X : zero-sequ. impedance reactance

12 38 DIST: Arc. comp. (circle) Fig. 25

Enabling / disabling the arc compensation.

Note: This setting is active for the setting DIST: Characteristic “Circle“ only.

12 40 DIST: Characteristic Fig. 18

Selection of the characteristic for the distance measurement.

12 41 DIST: ==== (circle) Fig. 26

This setting is of significance with the circular characteristic only when the setting

“With arc compensation“ is active. In this case, the setting of = determines the point at which arc compensation becomes active.

12 42 DIST: Z1 (circle) Fig. 27

12 43 DIST: Z2 (circle) Fig. 26

12 44 DIST: Z3 (circle) Fig. 26

12 45 DIST: Z4 (circle) Fig. 26

Impedance limit setting for impedance zones 1 to 4 in secondary values.

Note: Zone 4 can be used as a special zone (see D I S T : Z o n e 4 setting). This must be taken into account when setting Z4.

In document alstom pd521 (Page 120-124)