Schweitzer Engineering SEL-351P, Быстрый старт

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ii Overcurrent, Voltage, Synchronism Check, and Frequency Elements Date Code 990430
SEL-351P Manual Técnico
Residual Ground Time-Overcurrent Elements ...................................................................3-24
Settings Ranges ...........................................................................................................3-26
Accuracy .....................................................................................................................3-26
Negative-Sequence Time-Overcurrent Element .................................................................3-27
Settings Ranges ...........................................................................................................3-28
Accuracy .....................................................................................................................3-28
Voltage Elements........................................................................................................................3-29
Voltage Values....................................................................................................................3-29
Voltage Element Settings....................................................................................................3-29
Accuracy .....................................................................................................................3-34
Voltage Element Operation.................................................................................................3-34
Undervoltage Element Operation Example ................................................................3-34
Overvoltage Element Operation Example...................................................................3-35
Voltage Elements Used in POTT Logic .............................................................................3-35
Synchronism Check Elements ....................................................................................................3-35
Synchronism Check Elements Settings...............................................................................3-36
Accuracy .....................................................................................................................3-36
Synchronism Check Elements Voltage Inputs....................................................................3-38
System Frequencies Determined from Voltages V
A
and V
S
.......................................3-39
Synchronism Check Elements Operation ...........................................................................3-39
Voltage Window .........................................................................................................3-39
Other Uses for Voltage Window Elements .........................................................3-39
Block Synchronism Check Conditions .......................................................................3-40
Slip Frequency Calculator...........................................................................................3-40
Angle Difference Calculator .......................................................................................3-41
Voltages V
P
and V
S
are “Static”..........................................................................3-41
Voltages V
P
and V
S
are “Slipping” .....................................................................3-41
Angle Difference Example (voltages V
p
and V
s
are “slipping”).........................3-43
Synchronism Check Element Outputs.........................................................................3-44
Voltages V
P
and V
S
are “Static”..........................................................................3-44
Voltages V
P
and V
S
are “Slipping” .....................................................................3-44
Synchronism Check Applications for Automatic Reclosing and Manual Closing.............3-45
Frequency Elements....................................................................................................................3-46
Frequency Element Settings ...............................................................................................3-46
Accuracy .....................................................................................................................3-48
Create Over- and Underfrequency Elements ..............................................................3-48
Overfrequency Element.......................................................................................3-49
Underfrequency Element.....................................................................................3-49
Frequency Element Operation ............................................................................................3-49
Overfrequency Element Operation .............................................................................3-49
Underfrequency Element Operation ...........................................................................3-50
Frequency Element Voltage Control...........................................................................3-50
Other Uses for Undervoltage Element 27B81.....................................................3-50
Frequency Element Uses.....................................................................................................3-50