CHAPTER 5: SETTINGS
CONTROL ELEMENTS
N60 NETWORK STABILITY AND SYNCHROPHASOR MEASUREMENT SYSTEM – INSTRUCTION MANUAL
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Digitizer to prepare the measured power for sending to the UR-2 IED, and
direct outputs to send the digitized power to the UR-2 IED
For UR-2:
Digitizer to prepare the measured power for adding to the remote power,
direct inputs to receive the remote power from the UR-1 IED,
eight-bit comparator to sum the power values and apply a threshold, and
user-definable display messages for telemetry (optional)
The maximum active power at the UR-1 location is:
The maximum active power at the UR-2 location is:
For the two power values to be subsequently added, a common base must be selected for digitization. For this example, an
arbitrary value of 1500 MW is selected as a base and maximum value for digitization. Consequently, one count of digitized
power at either location is worth 1500 MW / 127 = 11.811 MW (see the Digitizers section in this chapter for details).
For the Digitizer at UR-1
1.
UR base unit for power given by P
BASE
= 345 kV x 2 kA = 690 MW (see the FlexElements section for details).
2.
The maximum power to be monitored (in pu) given by 1500 MW/690 MW = 2.174 pu.
3.
Apply the following settings:
DIGITIZER 1 SOURCE
: “SRC 1 P” and
DIGITIZER 1 LIMIT
= “2.174 pu”
For the Digitizer at UR-2
1.
UR base unit for power given by P
BASE
= 220 kV x 3 kA = 660 MW (see the FlexElements section for details).
2.
The maximum power to be monitored (in pu) given by 1500 MW/660 MW = 2.273 pu.
3.
Apply the following settings:
DIGITIZER 1 SOURCE
: “SRC 4 P” and
DIGITIZER 1 LIMIT
= “2.273 pu”
For the Direct Outputs at UR-1
1.
Assume that UR-1 IED is labeled as direct device 1 (
DIRECT OUTPUT DEVICE ID
= “1”).
2.
Assume that bits 1 to 8 are used for sending the required power to the UR-2 IED. Apply the following settings:
DIRECT OUT 1 OPERAND
: “DIGITIZER 1 BIT 0”
DIRECT OUT 5 OPERAND
: “DIGITIZER 1 BIT 4”
DIRECT OUT 2 OPERAND
: “DIGITIZER 1 BIT 1”
DIRECT OUT 6 OPERAND
: “DIGITIZER 1 BIT 5”
DIRECT OUT 3 OPERAND
: “DIGITIZER 1 BIT 2”
DIRECT OUT 7 OPERAND
: “DIGITIZER 1 BIT 6”
DIRECT OUT 4 OPERAND
: “DIGITIZER 1 BIT 3”
DIRECT OUT 8 OPERAND
: “DIGITIZER 1 BIT 7”
For the Direct Inputs at UR-2
1.
Apply the following settings (direct inputs 10 through 17 are used) to receive the digitized power from the UR-1 IED:
DIRECT INPUT 10 DEVICE ID
: “1”
DIRECT INPUT 10 BIT NUMBER
: “1”
DIRECT INPUT 11 DEVICE ID
: “1”
DIRECT INPUT 11 BIT NUMBER
: “2”
DIRECT INPUT 12 DEVICE ID
: “1”
DIRECT INPUT 12 BIT NUMBER
: “3”
DIRECT INPUT 13 DEVICE ID
: “1”
DIRECT INPUT 13 BIT NUMBER
: “4”
DIRECT INPUT 14 DEVICE ID
: “1”
DIRECT INPUT 14 BIT NUMBER
: “5”
DIRECT INPUT 15 DEVICE ID
: “1”