International

Ruleset

Ignore existing violations

Ignore any violations pre-existing in the grid and only consider the violations that become worse by the additional load/generation. The tolerance defines the threshold below which additional violations of existing violations will not be treated as violations.

INFO

If there are base case violations, the hosting capacity of the area within the evaluation scope is 0 kW. For more information check the FAQ.

Check for violations in...

Defines what part of the grid - starting from the evaluated node - should be considered for checking violations on the operational limits. This option can be used to limit the effect of base case violations. Formally, a base case violation is a violation that is present when running a power flow with no additional power.

Entire grid: The violations of the operational limits on elements in the entire grid are considered when evaluating a bus.

Transformer Circuit: The violations of the operational limits on elements within the same transformer circuit are considered when evaluating a bus.

Substation: Violations of the operational limits within the same substation of the evaluated bus are considered.

MV Feeder: Violations of the operational limits within the same medium voltage feeder of the evaluated bus are considered.

Feeder: Violations of the operational limits within the same feeder of the evaluated bus are considered.

Details

• Entire Grid: This option is the most conservative one.
• Transformer Circuit: This option makes sense for unsplit grids where individual transformer circuits are not supposed to have any interaction.
• Substation: A substation is a medium voltage transformer (with a secondary-side voltage between 1kV and 60kV). This option makes sense for unsplit grids where different substations (MV transformers) should not affect each other.
• MV Feeder: An MV feeder is the grid area served by a branch leaving the busbar of a substation (transformer with with a secondary-side voltage between 1kV and 60kV). In grids with stations, an MV feeder is a branch leaving a station of type Substation. This option makes sense for unsplit grids where different MV feeders should not affect each other.
• Feeder: A feeder is the grid area served by a branch leaving the bus bar of the transformer serving that bus. This option is the least conservative one. This option makes sense for split and unsplit grids, where different feeders should not affect each other.

TIP

Use the corresponding colorization options in the grid viewer () to visualize how an evaluation scope clusters the grid into different areas.

Consider highest voltage level

By deactivating this, the buses which are on the same voltage level as the network feeder are excluded from the calculation. In this case, only the buses on the undervoltage side of the transformer (limited by the transformer rating) are calculated.

Details

In some grids it can be observed that the hosting capacity in the area of the network feeder is extremely high. There are typically two things leading to this situation: low-impedance lines that hardly cause voltage change violations and branches without power limitation (connections and lines with undefined parameter 'Maximum Current'), which do not limit the power at all.

Violation checking

Check voltage violations in sibling grids

This setting defines if voltage violations in neighbouring grids - caused by additional load/generation in the evaluated grid - should be considered. This is done by considering the medium voltage grid in the power flow calculations.

INFO

A more detailed description of the logic can be found in Min./Max. Voltage Calculation

Operational Limits

There are 7 configurable operational limits of the grid:

• Bus voltage change: The voltage of no bus in the grid can change more than this percentage. The voltage change is determined by running 2 power flow calculations.
• Voltage unbalance factor: The voltage unbalance between phases, created by adding unbalanced load or generation, is restricted by this maximum value.
• Undervoltage: The voltage of all buses in the grid must be higher than this threshold
• Overvoltage: The voltage of all buses in the grid must be lower than this threshold
• Line loading: The loading of all lines in the grid must remain lower than this threshold. Line loading can only be evaluated if the maximum current $I_{max}$ is defined for each line.
• Transformer loading: The loading of all transformers in the grid must remain lower than this threshold. Transformer loading can only be evaluated if the maximum apparent power is defined for each transformer.
• Fuse loading: The loading of all fuses in the grid must remain lower than this threshold. The fuse loading can only be evaluated if the current rating is defined for each fuse.

Each of the operational limits can be switched off by unchecking the checkbox. At least one operational limit must be selected.

Power Factor

Define the absolute value of the power factor $\cos (\varphi )$.

Type

Defines the type of the power factor, which can be:

• Inductive
• Capacitive

Connection type category

Defines for which type of connections the hosting capacity should be calculated. Options are:

• Single-phase: Considers single-phase connections and lines in the hosting capacity calculation.
• Two-phase: Considers two-phase connections and lines in the hosting capacity calculation.
• Three-phase: Considers three-phase connections and lines in the hosting capacity calculation.

Details

Example: If a bus is only connected by a single-phase line (for example phase A) and connection type category single-phase is not chosen, the bus will receive a hosting capacity of 0.