DSATools™ Other DSA Tools Module | DYNRED Simplify Dynamic Power System Models

DYNRED starts with a set of models for a power system: powerflow and dynamics. For a specified set of system reduction creiteria, DYNRED reduces the system in the external region by replacing it with static and dynamic equivalents. The result is a smaller system model that allows fast computations for system performance analysis.

DYNRED can be used for:

• Development of base models for system planning.
• Building models for on-line dynamic security assessment.
• Construction of appropriate models for control system design and tuning.

• Reduction of large power system models for static and dynamic performance analysis
• Choice of reduction algorithms
• Compatibility in data formats with industry practices
• Performance benchmarking tools for reduced model validation
• Graphical user interface

To achieve the required reduction objectives, a set of criteria and methods can be specified:

• Regions of the system to be retained and to be reduced ("retained system specification").
• Grouping of generators in the external region ("coherency identification"). Choices can go from the simple weak link method to more advanced tolerance-based method.
• Handling of the coherent generators in the system ("generator aggregation"). Either classical or hybrid method can be used.

A reduced model created can be validated by using the performance metrics computed by DYNRED from various types of applications, including:

• Basic powerflow performance.
• Extended powerflow performance at post-contingency conditions.
• Time-domain performance from no-fault simulations and simulations for specified contingencies.
• Frequency-domain performance from comparison of dominant modes in the system.
• Stability limit comparison subject to voltage and transient criteria.

This example shows a dynamic reduction done using DYNRED for a large power system model. The following table gives the details on the full and reduced models.

Using the reduced model, the time it takes to complete a typical time-domain simulation is only 25.8% of the time for the full model. The figure below shows the quality of the reduced model.

Comparison of the time-domain simulation results for the rotor angle response of the same generator following a contingency.

• Processing power systems of up to 100,000 buses and 15,000 generators.
• Runs on MS Windows 7/10/server 2012 R2/server 2016