V&R Energy: Physical and Operational Margins (POM) - Load Flow, Contingency Analysis, Voltage Stability, Power Transfer Analysis
POM is a very powerful and highly automated power systems engineering application used for the steady-state stability analysis which includes load flow, AC contingency analysis, power transfer, and voltage stability analyses.
POM performs the AC contingency analysis extremely fast. The execution time for a 50,000-bus load flow case is approximately 50,000 contingencies per hour while simultaneously monitoring and enforcing voltage constraints, thermal overloads and steady-state stability, during the AC contingency analysis.
POM fully automates the N-1, N-1-1, N-2 AC contingency analysis tasks. It allows the users to apply millions of contingencies within one simulation run. There is no limit on a number of contingencies to be applied within a single run, or the number of buses in a load flow case. The application reads the existing load flow cases and contingency lists. Preparation of the input files is very simple, and massive contingency analysis may be performed by a simple click on the appropriate button.
POM offers the capability to perform very specific, user-defined studies by implementing a powerful and flexible scripting language. V&R offers assistance with custom scripts (a large pre-built library of scripts is included with the application) as part of out standard Maintenance and Support agreement.
POM is used in planning, operations and real-time environments. Major uses of POM include:
Automating NERC-compliance studies
- Massive fast N-1, N-1-1, N-2 AC contingency analysis
- Any scenario may be automated and simulated
- Automatic remedial actions when used along with Optimal Mitigation Measures (OPM)
- Database output and flexible reporting
- Uses existing contingency lists or generates generic N-1, N-2 contingency lists
- Different limits and solution parameters may be set for the N-0, N-1, N-2 contingencies within the same simulation run
Automated AC transfer/contingency analysis with visualization while simultaneously monitoring and enforcing voltage constraints, thermal overloads and steady-state stability
- Determines available transfer capability for each contingency
- Determines interface flows for each contingency at each transfer step
- Automatically builds PV-curves
Reliability Analysis
Outage Coordination
Graphical Capabilities of POM
POM allows the user to visually represent the monitored constraints while working in interactive modes. Very specific, user-defined graphical output is available when working in Script mode.
POM allows to visualize the power flow case through the use of the animated one-line diagrams and geographical maps. All of the graphical power system elements (generators, loads, transmission lines, transformers, etc.) are fully functional and can be switched in and out of service directly from the application screen. Full color one-line diagrams may be saved in a variety of graphical formats.
Methodology Incorporated in POM
The basis of POM is a fast and robust power flow solution algorithm. POM incorporates a nonlinear power system model. Full Newton method is used to solve the nonlinear power flow equations. The contingency screening technique utilizes the full AC analysis. In order to solve the large systems of nonlinear equations, POM incorporates the fast and effective sparse technique.
The concept of physical and operational margins consists of a physical margin and an operational margin. Operational margin is voltage stability margin. Physical margin incorporates the voltage and thermal limits. POM allows its users to determine the physical and operational margins while applying contingencies. Such margins are an important characteristic of each contingency.
The methodology used for AC contingency analysis has the capability to simultaneously monitor the Voltage Stability, Thermal, Voltage and Flowgate constraints.
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