IEEE Std 1159.3-2019 pdf download

IEEE Std 1159.3-2019 pdf download.IEEE Recommended Practice for Power Quality Data Interchange Format(PQDIF).
The tags in this obseration specifies an optional name “RMS Variation”, specifies the lime of creation of the record, the absolute time of the first data point in the data, and the time (if applicable) of the trigger that resulted in this observation being saved. Since this is a triggered event, the trigger method tag is specified to be of type channel indicating that a specific channel•based algorithm triggered the observation to be recorded. Additionally, the channel index array specifies which channel caused the trigger (channel index 19—phase B to C voltage—in this case). The tagChannclDefnldx indicates that this instancc data is for the channel definition 19 (zero-based index of IX) in the data source record as shown earlier,
The instance data itself contains the data tr the time and the value series. Each of these series is of the same length (59 entries) since the time series in this case specified its salues explicitly instead of using an increment. The value series use 2-byte integers to represent their values, which arc then sealed by the tagScriesScalc factor and then otYset by the tagScriesOffsct factor to get the engineering units for the recorded RMS trace points. Note that this instance did not specif’ the phase series, It is permissible to omit series instances even though they are defined for the channel. For the current version of PQDIF, there is no series index specified in the series instance, so the series instances arc position sensitive relative to their definitions, This means that to omit the max series, a tagoneScriesinstance tag must still be used as a place holder. If omitting series at the end of the collection of series instances, such place holders are not required.
Some instnjments capture one or more waveforms during an RMS variation in addition to the RMS trace. In this case, the data source record would have channel definitions for QT_WAVF.FORM type channels as well as for the QT_PHASOR channels. The observation would contain instances of the waveform and phasor channels as needed. A PQDIF reader program would generally display such an observation in a multi-pane plot—the waveform plot in one pane, the RMS trace plot in another, and the phase angle trace in yet another pane if available. Figure I (Ii I lustrates a plot of this type froni data captured by an instrument capable of simultaneous capture of the RMS envelope and waveform data.
7.4 RepresentIng periodIcally recorded steady state values
Fven though PQDIF is designed so represent power quality data. it also can represent steady state recordings of common clectric power characteristics. This data is analogous to recording values that might be gathered by a SCADA system that periodically reports these values or reports them when they exceed some threshold in the steady statc This data is generally gathered over a long period of time. The QT_VALUELOG type was designed to represent this type of data. From a purist point of view, the QT_VALUE LOG type could be used to represent thc RMS variation data discussed previously. In this case, however, the longer time frame steady-state log type data is separated Irum short duration variation data by
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The QT_VALUELOG channel type is used t create a channeli,cd representation of a steady state quantity log or a log of summary characteristics for disturbances. Such logs are common in a wide variety of instruments. These instruments periodically record the present value of a parameter in a simple lile or huller for later retrieval. These values are characteristics of the measured quantities or characteristics of values calculated from the measured quantities. The measured quantity may be voltage, but the recorded characteristic may be its RMS value, peak value, THD. third harmonic component. etc. Additionally, the minimum, maximum, and average values recorded for a characteristic during the reporting interval may also be recorded. Figure II illustrates a trend plot of total three-phase power at a 12.47 kV substation bus for a 4X-hour period. The instrument used to measure the power calculates the real power value once per second, saves the minimum, maximum, and average of the one second values every live minutes and then exports a PQDIF file once escry 24 hours.