Arcteq Generator Commander, Instruction Manual

Page: 348 / 561

Event block name Event names
GSYN Synchr. Increase Frequency OFF
GSYN Synchr. Decrease Frequency ON
GSYN Synchr. Decrease Frequency OFF
GSYN Synchronizer BRK Close ON
GSYN Synchronizer BRK Close OFF
GSYN Synchronizer Long Sync. Time ON
GSYN Synchronizer Long Sync. Time OFF
GSYN Synchroswitch Close fail Re-init ON
GSYN Synchroswitch Close fail Re-init OFF
GSYN Synchroswitching requested ON
GSYN Synchroswitching requested OFF
5.5.8 Vector jump (Δφ; 78)
Distribution systems may include different kinds of distributed power generation sources, such as wind
farms and diesel or fuel generators. When a fault occurs in the distribution system, it is usually detected
and isolated by the protection system closest to the faulty point, resulting in the electrical power system
shutting dow either partially or completely. The remaining distributed generators try to deliver the
power to the part of the distribution system that has been disconnected from the grid, and usually an
overload condition can be expected. Under such overload conditions, it is normal to have a drop in
voltage and frequency. This overload results in the final system disconnection from the islanding
generator(s). The disconnection depends greatly on the ratio between the power generation and the
demand of the islanded system. When any power is supplied to a load only from distributed generators,
(due to the opening of the main switch), the situation is called an isolated island operation or an
islanded operation of the electrical distribution network.
The vector jump control function is suitable to detect most islanding situations and to switch off the
mains breaker in order to let the generator only supply loads according to their rated power value.
Therefore, an overload does not cause any mechanical stress to the generator unit(s). The vector jump
relay should be located either on the mains side of the operated breaker or on the islanding generator
side.
The vector jump function is used for instant tripping and has only one operating stage. The function has
an algorithm which follows the samples of chosen measured voltages (64 samples/cycle). The
reference voltage used can be all or any of the phase-to-phase or phase-to-neutral voltages.
The outputs of the function are the ALARM, TRIP and BLOCKED signals. Both ALARM and TRIP
signals have an individual pick-up setting. The blocking signal and the setting group selection
control the operating characteristics of the function during normal operation, i.e. the user or user-
defined logic can change function parameters while the function is running. The vector jump function
uses a total of eight (8) separate setting groups which can be selected from one common source.
The operational logic consists of the following:
• input magnitude selection
• input magnitude processing
• threshold comparator
• two block signal checks (undervoltage block or stage external signal)
• time delay characteristics
• output processing.
Genera Generattor Commander or Commander
Instruction manual
Version: 2.07
346 © Arcteq Relays Ltd
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