Fluke 6135A/PMU, Руководство оператора

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6135A/PMU
Operators Manual
3-20
Standard Compliance Tests and Subtests
IEEE C37.118.1a-2014, Synchrophasor Measurements for Power Systems Specification
is the standard that mandates which tests are required to certify and verify UUT
performance. The three compliance tests types are steady state, dynamic, and message.
The subsequent sections describe each test.
Steady State Compliance Tests
A steady state compliance test is a “static test” where the magnitude, frequency, and
phase offset are constant and fixed for the duration of the test. Steady state compliance
tests make sure that the UUTs performance is within the range and limitations
IEEE
C37.118.1a-2014, “Steady State Compliance”
.
When a steady state test is started, the Timing Unit slews the nominally 30 MHz clock
frequency to align the 6105A Master Unit phase reference (
Refp
) with the 1 PPS. The
clock is set to exactly 30 MHz when alignment is achieved, and the 6105A Master Unit
output is at the nominal frequency (50 Hz or 60 Hz) with the L1 Phase voltage at zero
degrees (with reference to the 1 PPS). All other voltage and current outputs are aligned
with 1 PPS but offset by the phase angles set on the 6105A Master Unit to achieve a very
accurate balanced positive sequence output.
All tests begin at 1 PPS. This is zero time in the mathematical model known as
T0
. The
time stamp of the start of test (STU_T0) and the time of the positive edge of the Phase
Reference (STU_TRefp) are passed to the mathematical model of the 6105A Master Unit
output. When the PMU reports, the timestamp of the synchrophasor is used in the
mathematical model to calculate the “True” synchrophasor at that time. The two
synchrophasors are compared to determine the PMU error.
PMU tests include static signals at frequencies between nominal and up to ±5 Hz. This is
the maximum range of frequency for any PMU configuration. In non-nominal frequency
tests, the Synchrophasor 0˚ is not always aligned with 1 PPS. This does not matter as
long as there is alignment at the start of the test so that the mathematically generated
Synchrophasors are correct.
Some Static tests required by the
IEEE C37.118.1a-2014
standard include the application
of out-of-band interference. These are implemented in the Calibration System by
application of Harmonics and Interharmonics. The accuracy of Harmonics and
Interharmonics is reported in the 6105A Master Unit calibration certificate.
The steady state compliance tests compare Total Vector Error (TVE), Frequency Error
(FE), and Rate of change of Frequency Error (RFE) with these tests:
•
Signal Frequency Range Test
– These tests verify that limits are not exceeded for
a range of frequencies across the bandwidth of the UUT. The UUT bandwidth is
determined by the PMU configuration.
•
Voltage and Current Signal Magnitude
- These tests verify that the voltage and
current signal magnitude is not nominal.
•
Phase Angle
– These tests verify that limits are not exceeded when phase angles are
constant or slowly varying.
•
Harmonic Distortion
– These tests verify limits are not exceeded in the presence of
harmonics.
•
Out-of-band Interference (Interharmonics)
–These tests verify that limits are not
exceeded in the presence of out-of- band interfering signals.