pof_transformer_11_20kv {CNAIM}R Documentation

Current Probability of Failure for 6.6/11kV and 20kV Transformers

Description

This function calculates the current annual probability of failure for 6.6/11kV and 20kV transformers. The function is a cubic curve that is based on the first three terms of the Taylor series for an exponential function. For more information about the probability of failure function see section 6 on page 30 in CNAIM (2017).

Usage

pof_transformer_11_20kv(
  hv_transformer_type = "6.6/11kV Transformer (GM)",
  utilisation_pct = "Default",
  placement = "Default",
  altitude_m = "Default",
  distance_from_coast_km = "Default",
  corrosion_category_index = "Default",
  age,
  partial_discharge = "Default",
  oil_acidity = "Default",
  temperature_reading = "Default",
  observed_condition = "Default",
  reliability_factor = "Default"
)

Arguments

hv_transformer_type

String. Refers to the high voltage transformer type the calculation is done for. Options: hv_transformer_type = c("6.6/11kV Transformer (GM)", "20kV Transformer (GM)"). The default setting is hv_transformer_type = 6.6/11kV Transformer (GM).

utilisation_pct

Numeric. The max percentage of utilisation under normal operating conditions.

placement

String. Specify if the asset is located outdoor or indoor. A setting of "Outdoor" means the asset is located in an outside environment, and a setting of "Indoor" means the asset is located in an indoor environment. A setting of "Default" will result in either an indoor or an outdoor environment setting that depends on the specification of asset_type. See page 107-108, table 25A in CNAIM (2017) for default environments.

altitude_m

Numeric. Specify the altitude location for the asset measured in meters from sea level.altitude_m is used to derive the altitude factor. See page 107, table 23 in CNAIM (2017). A setting of "Default" will set the altitude factor to 1 independent of asset_type.

distance_from_coast_km

Numeric. Specify the distance from the coast measured in kilometers. distance_from_coast_km is used to derive the distance from coast factor See page 106, table 22 in CNAIM (2017). A setting of "Default" will set the distance from coast factor to 1 independent of asset_type.

corrosion_category_index

Integer. Specify the corrosion index category, 1-5. corrosion_category_index is used to derive the corrosion category factor. See page 107, table 24 in CNAIM (2017). A setting of "Default" will set the corrosion category factor to 1 independent of asset_type.

age

Numeric. The current age in years.

partial_discharge

String. Indicating the level of partial discharge. Options for partial_discharge: partial_discharge = c("Low", "Medium", "High (Not Confirmed)", "High (Confirmed)", "Default"). See page 138, table 159 in CNAIM (2017).

oil_acidity

Numeric. Measured in mg KOH/g. See page 138, table 160 in CNAIM (2017).

temperature_reading

String. Indicating the criticality. Options for temperature_reading: temperature_reading = c("Normal", "Moderately High", "Very High", "Default"). See page 139, table 161 in CNAIM (2017).

observed_condition

String. Indicating the observed condition of the transformer. Options for observed_condition: observed_condition = c("As New", "Good", "Slight Deterioration", "Poor", "Very Poor", "Default"). See page 120, table 73 in CNAIM (2017).

reliability_factor

Numeric. reliability_factor shall have a value between 0.6 and 1.5. A setting of "Default" sets the reliability_factor to 1. See section 6.14 on page 69 in CNAIM (2017).

Value

Numeric. Current probability of failure.

Source

DNO Common Network Asset Indices Methodology (CNAIM), Health & Criticality - Version 1.1, 2017: https://www.ofgem.gov.uk/system/files/docs/2017/05/dno_common_network_asset_indices_methodology_v1.1.pdf

Examples

# Current probability of failure for a 6.6/11 kV transformer
pof_transformer_11_20kv(hv_transformer_type = "6.6/11kV Transformer (GM)",
utilisation_pct = "Default",
placement = "Default",
altitude_m = "Default",
distance_from_coast_km = "Default",
corrosion_category_index = "Default",
age = 10,
partial_discharge = "Default",
oil_acidity = "Default",
temperature_reading = "Default",
observed_condition = "Default",
reliability_factor = "Default")

[Package CNAIM version 1.0.1 Index]