pof_cables_66_33kv {CNAIM} R Documentation

## Current Probability of Failure for 33-66kV cables

### Description

This function calculates the current annual probability of failure per kilometer for a 33-66kV cables. 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_cables_66_33kv(
cable_type = "66kV UG Cable (Gas)",
sub_division = "Aluminium sheath - Aluminium conductor",
utilisation_pct = "Default",
operating_voltage_pct = "Default",
sheath_test = "Default",
partial_discharge = "Default",
fault_hist = "Default",
leakage = "Default",
reliability_factor = "Default",
age
)
```

### Arguments

 `cable_type` String. A sting that refers to the specific asset category. See See page 15, table 1 in CNAIM (2017). Options: ```cable_type = c("33kV UG Cable (Gas)", "66kV UG Cable (Gas)", "33kV UG Cable (Non Pressurised)", "66kV UG Cable (Non Pressurised)", "33kV UG Cable (Oil)", "66kV UG Cable (Oil)") ```. The default setting is `cable_type = "66kV UG Cable (Gas)"`. `sub_division` String. Refers to material the sheath and conductor is made of. Options: ```sub_division = c("Aluminium sheath - Aluminium conductor", "Aluminium sheath - Copper conductor", "Lead sheath - Aluminium conductor", "Lead sheath - Copper conductor") ``` `utilisation_pct` Numeric. The max percentage of utilisation under normal operating conditions. `operating_voltage_pct` Numeric. The ratio in percent of operating/design voltage. `sheath_test` String. Only applied for non pressurised cables. Indicating the state of the sheath. Options: ```sheath_test = c("Pass", "Failed Minor", "Failed Major", "Default")```. See page 141, table 168 in CNAIM (2017). `partial_discharge` String. Only applied for non pressurised cables. Indicating the level of partial discharge. Options: ```partial_discharge = c("Low", "Medium", "High", "Default")```. See page 141, table 169 in CNAIM (2017). `fault_hist` Numeric. Only applied for non pressurised cables. The calculated fault rate for the cable in the period per kilometer. A setting of `"No historic faults recorded"` indicates no fault. See page 141, table 170 in CNAIM (2017). `leakage` String. Only applied for oil and gas pressurised cables. Options: ```leakage = c("No (or very low) historic leakage recorded", "Low/ moderate", "High", "Very High", "Default")```. See page 142, table 171 (oil) and 172 (gas) 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). `age` Numeric. The current age in years of the cable.

### Value

Numeric. Current probability of failure per annum per kilometre for 20/10/0.4kV cables.

### 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 annual probability of failure for
# "66kV UG Cable (Non Pressurised)", 50 years old
pof_cables_66kV_non <-
pof_cables_66_33kv(cable_type = "66kV UG Cable (Non Pressurised)",
sub_division = "Lead sheath - Copper conductor",
utilisation_pct = 80,
operating_voltage_pct = 60,
sheath_test = "Default",
partial_discharge = "Default",
fault_hist = "Default",
leakage = "Default",
reliability_factor = "Default",
age = 50) * 100

paste0(sprintf("Probability of failure %.4f", pof_cables_66kV_non),
" percent per annum")
```

[Package CNAIM version 1.0.1 Index]