Hitachi Relion 670 Series Applications Manual page 203

1MRK506375-UEN Rev. N
Umin: The minimum start level setting should be set as % of UBase. This setting enables the function
to start detecting delta. Typical setting is 10% of UBase. If the MeasMode setting is set as phase to
ground, this setting is taken as 50% of the set value.
MeasMode: To detect the mode of measurement; phase to phase or phase to ground.
OpMode: To select the mode of operation. For protection applications, this should be set to
Instantaneous 1 cycle old. Load supervision can be done using vector shift mode or DFT mag mode.
DelU>: To detect the start value for instantaneous sample, RMS, DFT mag based delta detection.
Set a typical value of 50% of UBase to use this function as fault detection.
DelUang>: This setting is used for angle based delta detection. This setting could be used to detect
islanding condition. A typical setting of 8-10 deg. is good to detect a major islanding condition.
DeltaT: This setting defines the number of old cycles data to be used for delta calculation in
RMS/DFT Mag and angle mode. Typical value is 2 cycles. This value is not used if OpMode is
chosen as instantaneous 1 cycle or instantaneous 2 cycle.
tHold: This setting defines the pulse length for supervision start signal. Typical value is 100 ms.
11.4 Current based delta supervision DELISPVC
11.4.1 Identification
Function description
Current based delta supervision
11.4.2 Application
In single phase networks, fault detection and operation of other protection functions is reliably done
by delta supervision functionality. Single phase traction networks are an important application of delta
supervision. In this type of network, typically for catenary protection, a delta based release criteria is
used to release the trip signal. The measurement of delta differs from country to country between
magnitude, vector or sample based detection.
In this function, a current based delta supervision is implemented in a phase segregated design. The
delta function has the following features:
• Instantaneous sample based delta detection (vectorial delta)
• True RMS value based delta detection
• DFT magnitude based delta detection
•
nd
2
•
rd
3
Instantaneous sample based delta supervision is very fast; the delta is detected in less than a cycle
typically. This mode can be used for high impedance earth fault detection. All the other supervision
modes like RMS/DFT Mag requires minimum one cycle for delta detection.
Therefore, the choice of delta detection mode should be based on the application requirement.
Instantaneous sample based delta supervision can be used for functions that are used as protection
enabler or fault detector. For time delayed functions, other modes can be used. Current based
function can be used for load supervision also in DFT Mag based delta mode.
Railway application RER670
Application manual
harmonic blocking of delta function
harmonic based adaption of starting value
© 2017 - 2023 Hitachi Energy. All rights reserved
IEC 61850 IEC 60617
identification identification
DELISPVC –
Section 11
Secondary system supervision
GUID-4F012876-FA0A-4A97-9E23-387974304CED v2
GUID-0B735A27-6A7D-40E1-B981-91B689608495 v1
ANSI/IEEE C37.2
device number
7I < >
GUID-5CEAE117-C7BA-46B6-BF24-477285050894 v2
197