Boundary-Based Solution, Automatic Nomogram Generation – Boundary of Operating Region (BOR)
BOR is an AC analysis tool that provides a boundary-based solution by identifying and graphically representing the region within which the system operation is secure.
Fully integrated into the POM Suite, BOR is a quick, convenient tool to determine and graphically display a region within which no violations of the monitored and enforced constraints occur. The graphical output of BOR is a boundary of the operating region. Operating within the boundary is secure. Each point on the boundary corresponds to at least one of the constraints being violated. The monitored and enforced constraints are:
- Thermal violation
- Voltage range violation
- Pre- to post-contingency voltage drop violation
- Voltage stability violation
When used along with the transient stability (TS) module, BOR allows the user to compute the dynamic security region.
The main uses of BOR include:
- Computing simultaneous power transfer limits.
- Displaying the effect of contingencies on both the size of the secure operating region and the limiting constraints.
- Determining the most effective remedial actions and their effect on the secure region of operation when used with OPM.
- Automating the process of constructing seasonal nomograms.
- Determining various power transfer scenarios with the purpose of achieving the maximum transfer capability without any additional investments.
- Performing conditional firm analysis.
BOR Capabilities
The primary purpose of BOR is to analyze any number of simultaneous power transfers and determine the impact of each transfer on all other transfers. BOR computes the AC limits for the simultaneous power transfers based on voltage stability, voltage constraints and thermal constraints. The user has the flexibility to achieve each transfer by varying the generation and/or load in the areas of interest in user-defined and specified ways.
BOR also provides the users with the capability to study the behavior of a power system while changing any user-defined power network parameters, such as:
- Real and reactive components of load and generation;
- Transformer tap ratio and phase angle of phase-shifting transformers;
- Scheduled voltage setpoint at bus;
- Shunt admittance of a discrete shunt and reactive component of bus shunt admittance; and
- Any other user-defined power network parameter.
BOR offers the capability to automatically rank contingencies based on the size of each operating region. BOR also automatically determines the secure operating region that satisfies N-1 and N-2 reliability criteria.BOR may be graphically exhibited as a projection onto different coordinate planes of the power system parameters, such as:
- Power transfers
- Load and generation
- Interface and/or tie-line flows