Fluke 6135A/PMU, Руководство оператора

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Software Operation
Standard Compliance Tests and Test Files
3
3-21
Dynamic Compliance Tests
A dynamic compliance test type is where the magnitude, frequency, and phase offset vary
depending on the type of test. Dynamic compliance tests make sure that the UUTs
performance is within the range and limitations in
IEEE C37.118.1a-2014 “Dynamic
Compliance”
.
The dynamic compliance tests compare TVE, FE and RFE with these tests:
•
Modulation (Measurement Bandwidth)
– These tests verify limits are not
exceeded when the input voltage and current are phase modulated and phase and
amplitude modulated together. Modulation is achieved by modulating the 30 MHz
clock to achieve ±0.5 Hz from nominal at up to 5 Hz/s at the 6135A outputs. Testing
starts at the 1 PPS to synchronize the mathematical model. Amplitude modulation of
up to ±10 % at up to 5 Hz/s is applied using the fluctuating harmonics feature of the
6105A Master Unit. The hardware trigger from the STU to the 6105A Master Unit
ensures the actual output and mathematical model are aligned.
•
Frequency Ramp
– These tests verify limits are not exceeded when the input
frequency is linearly ramped. Frequency Ramp tests vary frequency linearly by up to
± 5 Hz from nominal at 1 Hz/s. The ramp starts before the start frequency to avoid
sudden frequency changes which would cause significant Rate of Change of
Frequency Error within the “measurement window”. As with phase modulation the
input clock frequency is ramped to change the 6105A Master Unit output frequency.
The Calibration System applies a frequency correction factor in the mathematical
model to compensate for phase delays in the 6105A Master Unit circuitry and ensures
the “True” Synchrophasor is correct. This correction is also applied in phase
modulation and static non-nominal frequency tests.
•
Step
– A different set of measures apply to Step tests. These tests verify response
time, delay, maximum overshoot/undershoot, frequency response time, and rate of
change of frequency response time. Limits are not exceeded when an input
magnitude or phase angle step is applied. The criteria for step tests are different to the
other types of test. Steps are ±10 % Amplitude or ±10˚ Phase Angle. The parameters
measured in step tests are Delay Time, Response Time and Maximum Undershoot
/Overshoot. The accuracy of amplitude steps is determined by the 6105A Master Unit
performance. The Hardware Trigger from the Timing Unit to the 6105A Master Unit
trigger input ensures steps occur at the correct time. The Timing Unit controls phase
angle steps and checking this is one of the tests in the User verification process
below.