Signal Reference Notes:
For synchrophasor measurements the signal reference field is critical - it is used to map device elements in a protocol frame (e.g., IEEE C37.118) to and from measurements. The format of this field is very regular:
The text based signal reference field must contain the Acroynm of the associated Device, followed by a dash (‘-‘), followed by the two character SignalType Suffix then optionally followed by an index. Note that the mapping
is by order, not by index or name. Thus, it is critical that the indexed measurements be modeled in the order that they are returned from the source device. For example SHELBY-PM4 represents the fourth phasor magnitude for the SHELBY Device and
SHELBY-SF represents its status flags.
The information below describes the original specification:
In order to rebroadcast data from the sub-second sources, a field is required to be able to associate each point with its associated "field" in a synchrophasor protocol data frame. This document defines these relations.
This field will normally be for internal use only and be stored in a synonym style field for each defined measurement point:
| Type of Point |
Abbreviation |
Indexed? |
Phasor Magnitude
(aka. Voltage (Volts) or Current (Amps)) |
PM |
Yes |
Phasor Angle
(aka. Angle (Degrees)) |
PA |
Yes |
Frequency
(aka. Frequency (Hz)) |
FQ |
No |
dF/dt
(aka. Frequency rate of change) |
DF |
No |
| Digital Value |
DV |
Yes |
Status Flags
(aka. PMU status bytes) |
SF |
No |
Suggestion is to assign a format of: the PMU acronym, a dash and one of the above abbreviations (others could be added). Also, if the type of point is indexed, adding the associated entry index, for example:
SHEL-PM1
ß Magnitude associated with Phasor1 entry
SHEL-PA1
ß Angle associated with Phasor1 entry
SHEL-PM2
ß Magnitude associated with Phasor2 entry
SHEL-PA2
ß Angle associated with Phasor2 entry
SHEL-PM3
ß Magnitude associated with Phasor3 entry
SHEL-PA3
ß Angle associated with Phasor3 entry
SHEL-PM4
ß Magnitude associated with Phasor4 entry
SHEL-PA4
ß Angle associated with Phasor4 entry
SHEL-PM5
ß Magnitude associated with Phasor5 entry
SHEL-PA5
ß Angle associated with Phasor5 entry
SHEL-FQ
ß Frequency value associated with Frequency entry
SHEL-DF
ß Rate of frequency change associated with Frequency entry
SHEL-DV1
ß Digital Value 1
SHEL-DV2
ß Digital Value 2
SHEL-SF
ß Status Flags
Using this information you should be able to map to and from most any synchrophasor protocol data frame.