Directional Power Unit (32) - GE Multilin F650 Instruction Manual

5 SETPOINTS 5.4 PROTECTION ELEMENTS

5.4.9.2 DIRECTIONAL POWER UNIT (32)

a) UNIT DESCRIPTION
The Directional Power element responds to three-phase active power measured from the feeder associated to the F650.
This element can be selected to operate according to the power threshold adjusted in the corresponding setpoint. This
element is ideal for reverse power applications (F32 REV) or forward power (F32 FWD), depending on the selected
setpoint. The relay measures the three-phase power for wye or delta connections.
The element has an adjustable characteristic angle and minimum operating power as shown in the Directional Power
Characteristic diagram. The element responds to the following condition:
P cos(ϕ) + Q sin (ϕ) > SMIN
where: P and Q are active and reactive powers as measured per the F650 convention, ϕ is the angle set at the 32 setpoint
(DIR POWER ANGLE) in degrees in steps of 0.01º, and SMIN is the minimum operating power
The element has two independent (as to the pickup and delay setpoints) units. Both units can be used for alarm and trip,
and they can be set separately to provide a mixed power protection.
The Directional Power Characteristic is shown in the following diagram.
5
Figure 5–16: POWER DIRECTIONAL CHARACTERISTIC
By making the characteristic angle adjustable from 0º to 360º in steps of 0.01º, a variety of operating characteristics can be
achieved as presented in the figures below. For example, for an angle of 0º, the unit would operate as a 32 Forward Power
element, while if setpoint an RCA angle of 180º, the unit would operate as a 32 Reverse Power element. For angles of 90º
and 270º, the case would be similar but with reactive power.
GE Multilin F650 Digital Bay Controller 5-71