GE N60 Instruction Manual

Also see for N60: Communications manual Communications guide Instruction manual Instruction manual Instruction manual

Contents

CHAPTER 5: SETTINGS GROUPED ELEMENTSN60 NETWORK STABILITY AND SYNCHROPHASOR MEASUREMENT SYSTEM – INSTRUCTION MANUAL 5-1755POWER SWING QUAD REV REACH MID — This setting specifies the reverse reach of the middle quadrilateral characteristic.The angle of this reach impedance is specified by the POWER SWING FWD RCA setting. The setting is not used if the shapesetting is “Mho.”POWER SWING QUAD REV REACH OUT — This setting specifies the reverse reach of the outer quadrilateral characteristic. Theangle of this reach impedance is specified by the POWER SWING FWD RCA setting. The setting is not used if the shapesetting is “Mho.”POWER SWING REV RCA — This setting specifies the angle of the reverse reach impedance for the mho characteristics. Thissetting applies to mho shapes only.POWER SWING OUTER LIMIT ANGLE — This setting defines the outer power swing characteristic. The convention depicted inthe power swing detect mho operating characteristic diagram are to be observed: values greater than 90° result in anapple-shaped characteristic; values less than 90° result in a lens-shaped characteristic. This angle must be selected inconsideration of the maximum expected load. If the maximum load angle is known, coordinate the outer limit angle with a20° security margin. Detailed studies can be needed for complex systems to determine this setting. This setting applies tomho shapes only.POWER SWING MIDDLE LIMIT ANGLE — This setting defines the middle power swing detect characteristic. It is relevant onlyfor the three-step mode. A typical value is close to the average of the outer and inner limit angles. This setting applies tomho shapes only.POWER SWING INNER LIMIT ANGLE — This setting defines the inner power swing detect characteristic. The innercharacteristic is used by the out-of-step tripping function: beyond the inner characteristic out-of-step trip action is definite(the actual trip can be delayed as per the TRIP MODE setting). Therefore, this angle must be selected in consideration to thepower swing angle beyond which the system becomes unstable and cannot recover.The inner characteristic is also used by the power swing blocking function in the two-step mode. In this case, set this anglelarge enough so that the characteristics of the distance elements are safely enclosed by the inner characteristic. Thissetting applies to mho shapes only.POWER SWING OUTER, MIDDLE, and INNER RGT BLD — These settings specify the resistive reach of the right blinder. Theblinder applies to both “Mho” and “Quad” characteristics. Set these value high if no blinder is required for the “Mho”characteristic.POWER SWING OUTER, MIDDLE, and INNER LFT BLD — These settings specify the resistive reach of the left blinder. Enter apositive value; the relay automatically uses a negative value. The blinder applies to both “Mho” and “Quad” characteristics.Set this value high if no blinder is required for the “Mho” characteristic.POWER SWING PICKUP DELAY 1 — All the coordinating timers are related to each other and need to be set to detect thefastest expected power swing and produce out-of-step tripping in a secure manner. Set the timers in relation to the powerswing detect characteristics, mode of power swing detect operation, and mode of out-of-step tripping. This timer definesthe interval that the impedance locus must spend between the outer and inner characteristics (two-step operating mode),or between the outer and middle characteristics (three-step operating mode) before the power swing blocking signal isestablished. This time delay must be set shorter than the time required for the impedance locus to travel between the twoselected characteristics during the fastest expected power swing. This setting is relevant for both power swing blockingand out-of-step tripping.POWER SWING RESET DELAY 1 — This setting defines the dropout delay for the power swing blocking signal. Detection of acondition requiring a block output sets latch 1 after PICKUP DELAY 1 time. When the impedance locus leaves the outercharacteristic, timer POWER SWING RESET DELAY 1 is started. When the timer times-out, the latch is reset. Select this settingto give extra security for the power swing blocking action.POWER SWING PICKUP DELAY 2 — Controls the out-of-step tripping function in the three-step mode only. This timer definesthe interval the impedance locus must spend between the middle and inner characteristics before the second step of theout-of-step tripping sequence is completed. This time delay must be set shorter than the time required for the impedancelocus to travel between the two characteristics during the fastest expected power swing.POWER SWING PICKUP DELAY 3 — Controls the out-of-step tripping function only. It defines the interval the impedance locusmust spend within the inner characteristic before the last step of the out-of-step tripping sequence is completed and theelement is armed to trip. The actual moment of tripping is controlled by the TRIP MODE setting. This time delay is providedfor extra security before the out-of-step trip action is executed.