OeS 6 software is intended for modeling and calculation of radial and multiply closed power networks, under operating and short-circuit conditions. The program’s computational capabilities allow for the analysis of the operation of HV, MV and LV networks within one model. The program is also equipped with modules supporting the selection of protection settings and determining the load capacity of cables depending on the installation conditions. OeS has always been created as an engineering tool – it is characterized by transparency and simplicity of use, while maintaining a full range of computational functionalities for the implementation of analytical and design tasks.

Individual OeS software modules allow you to perform power flow and short-circuit calculations, which are an indispensable element of every project or connection expertise. Available functionalities enable, among others: proper selection of devices with regard to operation in operating and short-circuit conditions, solving problems related to reactive power compensation or assessment of the operation of the neutral point. They also support planning the expansion of the existing network and help in making connection decisions. In the OeS software, you can quickly perform calculations for any network configuration, which opens up great opportunities for users to create multi-variant analyses.

Functionalities related to modeling and analysis of network security operation have also been developed for many years. The user can analyze the sensitivity and selectivity of protections, determine their response times, and assess the risk of shock. Additionally, OeS can be equipped with the PROKAB module, which allows for the creation and calculation of the longitudinal and transverse profiles of the cable and the determination of substitute parameters for overhead lines. Another additional element is the GRAFIK module, which allows for the modeling of consumers taking into account the variability of the load over time (operator’s tariff or measurement data) and the modeling of prosumers taking into account the variability of their generation. The possibility of using the ENTSO-E database (climate years) has been implemented here, taking into account the weather forecast in the calculations or entering measurement data. Computational functionalities allow for the analysis of time histories of power and branch currents, voltages in network nodes, losses and other network parameters.

Harmonics

The module is used to perform calculations under deformed loads and sources. The input data to the module are the shares of individual higher harmonics, both active and reactive, in the load (non-rotating load or engine) and those generated by the source (static source or rotating generator). The result of the calculations is the flow of higher active and reactive harmonics for all branches of the network and the levels of voltage harmonics in the network nodes. The calculation results also include the values of the fundamental harmonic.

Harmonic calculations make it possible to determine the share of higher harmonics in branch currents and voltages of network nodes, as well as to determine the THD (Total Harmonic Distortion) harmonic distortion coefficient.

The OeS program allows you to determine the relative load from higher harmonics for the following elements:

  • power network,
  • energy consumer,
  • asynchronous machine,
  • synchronous machine,
  • shunt compensator.

The program allows you to enter data up to the 50th harmonic. The parameters are defined separately for active and passive load, as a percentage of the basic component.

After defining the parameters of higher harmonics in the network elements, an analysis of the flow of higher harmonics can be performed for the entire model.

Rough calculation results are presented in the form of a graph in a “bubble” when you hover over the element

Detailed analysis results are included in the appropriate calculation results table:

  • node results:
    • U (kV) – branch voltage,
    • THD (%) – higher harmonic content coefficient,
    • |Unh| (kV) – module of the nodal voltage of the nth harmonic,
    • Re{Unh} (kV) – active component of the nodal voltage of the nth harmonic,
    • Im{Unh} (kV) – reactive component of the n-th harmonic nodal voltage,
    • |Unh| (%) – relative value of the nodal voltage module of the n-th harmonic related to the fundamental component,
    • Re{Unh} (%) – relative value of the active component of the nodal voltage of the n-th harmonic related to the fundamental component,
    • Im{Unh} (%) – relative value of the reactive component of the nodal voltage of the n-th harmonic related to the fundamental component,
  • branch results:
    • U (kV) – branch voltage,
    • THD (%) – higher harmonic content coefficient,
    • |Inh| (kA) – branch current modulus of the nth harmonic,
    • Re{Inh} (kA) – active component of the n-th harmonic branch current,
    • Im{Inh} (kA) – reactive component of the n-th harmonic branch current,
    • |Inh| (%) – relative value of the branch current module of the n-th harmonic related to the fundamental component,
    • Re{Inh} (%) – relative value of the active component of the branch current of the n-th harmonic related to the fundamental component,
    • Im{Inh} (%) – relative value of the reactive component of the branch current of the n-th harmonic related to the fundamental component,