ABB RELION 620 Series Technical Manual page 632

Section 4
Protection functions
4.5
4.5.1
4.5.1.1
4.5.1.2
4.5.1.3
4.5.1.4
626
Voltage protection
Three-phase overvoltage protection PHPTOV
Identification
Function description
Three-phase overvoltage protection
Function block
GUID-871D07D7-B690-48FD-8EA1-73A7169AE8BD V2 EN
Figure 321: Function block
Functionality
The three-phase overvoltage protection function PHPTOV is applied on power
system elements, such as generators, transformers, motors and power lines, to protect
the system from excessive voltages that could damage the insulation and cause
insulation breakdown. The three-phase overvoltage function includes a settable value
for the detection of overvoltage either in a single phase, two phases or three phases.
PHPTOV includes both definite time (DT) and inverse definite minimum time
(IDMT) characteristics for the delay of the trip.
The function contains a blocking functionality. It is possible to block function outputs,
timer or the function itself, if desired.
Operation principle
The function can be enabled and disabled with the Operation setting. The
corresponding parameter values are "On" and "Off".
The operation of PHPTOV can be described using a module diagram. All the modules
in the diagram are explained in the next sections.
IEC 61850 IEC 60617
identification identification
PHPTOV 3U>
1MRS757644 F
ANSI/IEEE C37.2
device number
59
620 series
Technical Manual