pof_future_cables_66_33kv {CNAIM}R Documentation

Future Probability of Failure for 33-66kV cables

Description

This function calculates the future 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_future_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,
  simulation_end_year = 100
)

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.

simulation_end_year

Numeric. The last year of simulating probability of failure. Default is 100.

Value

Numeric array. Future probability of failure per annum per kilometre for 33-66kV 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

# Future probability of failure for 66kV UG Cable (Non Pressurised)
pof_66kV_non_pressurised <-
pof_future_cables_66_33kv(cable_type = "66kV UG Cable (Non Pressurised)",
sub_division = "Aluminium sheath - Aluminium conductor",
utilisation_pct = 75,
operating_voltage_pct = 50,
sheath_test = "Default",
partial_discharge = "Default",
fault_hist = "Default",
leakage = "Default",
reliability_factor = "Default",
age = 1,
simulation_end_year = 100)
# Plot
plot(pof_66kV_non_pressurised$PoF * 100,
type = "line", ylab = "%", xlab = "years",
main = "PoF per kilometre - 66kV UG Cable (Non Pressurised)")

[Package CNAIM version 1.0.1 Index]