Thu, 2024-04-04 13:56 — RV-C Admin

Justification:

The following additions are proposed to the DC Source status and configuration DGNs

Objections were corrected in the new document. Objection was resolved.

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6.5.25 - 29. DC Source DGN Additions.docx | 26.31 KB |

## Would the following edits

Would the following edits sufficiently clarify this to resolve the concern?

Bits 3.0-3.3 Current Smoothing Algorithm

0 = no smoothing

1 = exponential weighted moving average:

st = (1/N)xt + (1 – 1/N)st-1

where st is the new average

and st-1 is the previous average

and xt is the new data

and N is determined by smoothing period

2 = boxcar (unweighted) moving average

st =1/N Σxi for i = (t-N+1) to t

15 = no change/not supported

Bits 3.4-3.7 Voltage Smoothing Algorithm . . . .

Byte 4 Current Smoothing Period

This parameter can be used to change the smoothing period used for the reported Current measurements in DC Source Status 1.

Resolution is 0.1s, with a range of 0.1 to 25.0 seconds.

For both smoothing methods, N = tsmooth/tsamp

Where tsmooth is this parameter and tsamp is the internal Current sample rate, both in seconds.

Note: If unused, assumed to match the DC Source Status 1 Normal Broadcast Gap.

Byte 5 Voltage Smoothing Period

This parameter can be used to change the smoothing period used for the reported Voltage measurements in DC Source Status 1.

Resolution is 0.1s, with a range of 0.1 to 25.0 seconds.

For both smoothing methods:

N = tsmooth/tsamp

Where tsmooth is this parameter and tsamp is the internal Voltage sample rate, both in seconds.

Note: If unused, assumed to match the DC Source Status 1 Normal Broadcast Gap.

## This answers my objection

This answers my objection admirably.

For readability, I suggest putting the bulk of the text in the text block following the table, rather than in the table itself.

## OBJECTION On

OBJECTION

On DC_SOURCE_CONFIGURATION_COMMAND_4

Current Time Constant / Voltage Time Constant.

There are several algorithms that can be used to smooth and sample this sort of data. It isn't clear which is intended, and for no algorithm is there enough information here to fully describe the parameters. From the Name and Description, I would guess that Exponential Smoothing is what is intended. From the Unit, I would assume a Moving Average. In the first case, there are two parameters of interest - the sampling rate and the smoothing factor. In the latter case, only the sampling rate is required.

These are just two possibilities - there are lots of other algorithms available. Intuitively, a Moving Average would be more appropriate for Current, Exponential Smoothing for Voltage, but there are a number of factors to consider.

I suggest something like:

Bits 3.0-3.3 Current Smoothing Algorithm 0 = Single Sample. 1 = Moving Average. 2 = Exponential Smoothing.

Bits 3.4-3.7 Voltage Smoothing Algorithm . . . .

Byte 4 Current Sample Rate (0.1 sec)

Byte 5 Current Smoothing Constant

Byte 6 Voltage Sample Rate (0.1 sec)

Byte 7 Voltage Smoothing Constant