Schweitzer Engineering Laboratories SEL-300G, Инструкция по эксплуатации

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SEL
OGIC
Control Equations 4-5
SEL-300G Instruction Manual Date Code
20060731
The Relay Word bits in this factory setting example are:
24C2 Measured generator volts/hertz equal to or above the pickup setting for the
24C2 volts/hertz element (see Figure 2.13).
32P1 Measured real power less than the pickup setting for the 32P1 reverse/low-
forward power element (see Figure 2.15).
46Q2 Measured negative-sequence current greater than the pickup setting for the
46Q2 negative-sequence time-overcurrent element (see Figure 2.19).
When setting ER sees a logical 0 to logical 1 transition, the relay generates an event report if it is
not already generating a report that encompasses the new transition. The rising edge operators
cause a logical 0 to logical 1 transition (thus triggering a new report) each time one of the
protection elements asserts. Using these settings, the relay triggers a new event report each time
any of the protection elements assert, if the relay is not already recording an event report.
SEL
OGIC
Control Equation Falling Edge Operator, \
The falling edge operator, \, is applied to individual Relay Word bits only—not to groups of
elements within parentheses. The falling edge operator, \, operates similarly to the rising edge
operator, but looks for Relay Word bit deassertion (element going from logical 1 to logical 0).
The falling edge operator, \, in front of a Relay Word bit sees this logical 1 to logical 0 transition
as a “falling edge” and asserts to logical 1 for one processing interval.
For example, suppose the SEL
OGIC
control equation event report generation setting is set with the
detection of the falling edge of an underfrequency element:
ER = ... + \81D1T
When frequency goes above the corresponding pickup level 81D1P, Relay Word bit 81D1T
deasserts and an event report is generated (if the relay is not already generating a report that
encompasses the new transition). This allows a recovery from an underfrequency condition to be
observed. Figure 4.1 demonstrates the action of the falling edge operator, \, on the
underfrequency element in setting ER.
DWG: M300G160
one processing interval
\81D1T
81D1T
Figure 4.1: Result of Falling Edge Operator on a
Deasserting Underfrequency Element
SEL
OGIC
Control Equation Parentheses Operator, ( )
More than one set of parentheses ( ) can be used in a SEL
OGIC
control equation setting. For
example, the following SEL
OGIC
control equation setting has two sets of parentheses:
SV7 = (SV7 + IN103 + TRIP1) * (50H1 + 50R1 + 52A)
In the above example, the logic within the parentheses is processed first and then the two
parentheses resultants are ANDed together. The above example is from Figure 4.28 in this