Loadflow Module

Inheritance diagram of Loadflow

ERACS Loadflow engine interface. This module is crucial for many types of studies, as other calculations such as Fault, Harmonic Injection and Harmonic Impedance depend on steady-state results produced by Loadflow.

class TEracsLoadflow

Low-level implementation of the Loadflow interface. All low-level methods in this class interact directly with the DLL procedures.

Inherits

Calculations.TEracsModule.

property VersionNumber

Version number of the calculation module.

Type

str.

Writable

False.

property ProgramNumber

Program number of the calculation.

Type

int.

Writable

False.

Example

1 = Loadflow

SetupCalculation(ASetupSimple)

The first method to call in the Loadflow DLL. It passes all required calculation parameters needed to run Loadflow.

Parameters

ASetupSimple (TLFSetUpData) – The setup data object, passes the Loadflow setup parameters to Loadflow.

Returns

True if successful.

LoadBusbarData(ABusbarData)

Loads a busbar into the Loadflow engine.

Parameters

ABusbarData (TLFBusData) – The busbar data.

LoadLineData(ATransmissionLineData)

Loads a transmission line into the Loadflow engine.

Parameters

ATransmissionLineData (TLFLineCableData) – The transmission line data.

LoadCableData(ACableData)

Loads a cable into the Loadflow engine.

Parameters

ACableData (TLFLineCableData) – The cable data.

LoadSeriesElementData(ASeriesElementData)

Loads a series element into the Loadflow engine.

Parameters

ASeriesElementData (TLFSeriesElementData) – The series element data.

LoadTapData(ATapChangerData)

Loads a tap changer into the Loadflow engine.

Parameters

ATapChangerData (TLFTapData) – The tap changer data.

LoadTxData(ATransformerData)

Loads a transformer into the Loadflow engine.

Parameters

ATransformerData (TLFTxData) – The transformer data.

LoadIndMachineData(AInductionMachineData)

Loads an induction machine into the Loadflow engine.

Parameters

AInductionMachineData (TLFIndMachData) – The induction machine data.

LoadSyncMachineData(ASynchronousMachineData)

Loads a synchronous machine into the Loadflow engine.

Parameters

ASynchronousMachineData (TLFSyncMachData) – The synchronous machine data.

LoadInfiniteGeneratorData(AInfiniteGeneratorData)

Loads an infinite generator/grid infeed into the Loadflow engine.

Parameters

AInfiniteGeneratorData (TLFInfGenData) – The infinite generator data.

LoadShuntData(AShuntData)

Loads a shunt connected load into the Loadflow engine.

Parameters

AShuntData (TLFShuntData) – The shunt data.

LoadBusSectionData(ABusSectionData)

Loads a bus section into the Loadflow engine.

Parameters

ABusSectionData (TLFBusSectionData) – The bus section data.

GetTDFBlock(ATDFBlockObject)

The TDF block is generated from the Loadflow module, and is used to quickly and easily pass data onto other dependent calculation modules after running Loadflow. This method loads the TDF block from memory.

Parameters

ATDFBlockObject (TEracsTdfBlock) – The TDF block to populate with data.

DisposeTDFBlock()

Dispose the TDF block which was loaded up from memory.

GetFileNames(AOutParameterList)
Parameters

AOutParameterProperties (list) – This argument acts as an out parameter. An empty list should be passed in, and the various file names will be appended to the list [lstResults, cdResults, cdData].

class TEracsLoadflowEasy

High-level implementation of the Loadflow interface. All methods interact with the low-level class and NOT the DLL procedures directly.

Inherits

Calculations.TEracsEasy.

property TdfBlock

The TDF block generated from Loadflow and needed for Fault, Harmonic Impedance and other Loadflow-dependent calculation modules.

Type

TEracsTdfBlock

Writable

False.

property SummaryResults

Summary results from the Loadflow study.

Type

dict.

Writable

False.

property BusbarResults

Busbar results from the Loadflow study.

Type

TEracsListResult

Writable

False.

property TransmissionLineResults

Transmission line results from the Loadflow study.

Type

TEracsListResult

Writable

False.

property CableResults

Cable results from the Loadflow study.

Type

TEracsListResult

Writable

False.

property SeriesElementResults

Series element results from the Loadflow study.

Type

TEracsListResult

Writable

False.

property TapChangerResults

Tap changer results from the Loadflow study.

Type

TEracsListResult

Writable

False.

property TransformerResults

Transformer results from the Loadflow study.

Type

TEracsListResult

Writable

False.

property InductionMachineResults

Induction machine results from the Loadflow study.

Type

TEracsListResult

Writable

False.

property SynchronousMachineResults

Synchronous machine results from the Loadflow study.

Type

TEracsListResult

Writable

False.

property GridInfeedResults

Grid infeed results from the Loadflow study.

Type

TEracsListResult

Writable

False.

property ShuntResults

Shunt results from the Loadflow study.

Type

TEracsListResult

Writable

False.

property BusSectionResults

Bus section results from the Loadflow study.

Type

TEracsListResult

Writable

False.

property CsvDataFileName

CSV data file path and name, generated from Loadflow.

Type

str.

Writable

False.

property BusbarsOutOfVoltageRange

A list of all busbars which are outside of their voltage range in the Loadflow study. This will return an empty list if the Loadflow study has yet to be performed.

Type

list.

Writable

False.

property OverloadedElements

A list of all elements which are overloaded in the Loadflow study. This will return a dictionary containing keys of the different element typecodes. The data for each key will be the list of elements of that type which were overloaded. If the Loadfow study is yet to be performed, each list in each key will be empty.

Type

dict.

Writable

False.

property BaseMva

The base MVA Loadflow parameter to be passed in when setting up.

Type

float.

Writable

True.

property BaseFrequency

The base frequency (Hz) Loadflow parameter to be passed in when setting up.

Type

float.

Writable

True.

property ConvergenceTolerance

The convergence tolerance (pu) Loadflow parameter to be passed in when setting up.

Type

float.

Writable

True.

property NumberOfIterations

The number of iterations Loadflow parameter to be passed in when setting up.

Type

int.

Writable

True.

property OverloadThreshold

The overload threshold (pu) Loadflow parameter to be passed in when setting up.

Type

float.

Writable

True.

property PMultiplier

The shunt real power multiplier Loadflow parameter to be passed in when setting up.

Type

float.

Writable

True.

property QMultiplier

The shunt reactive power multiplier Loadflow parameter to be passed in when setting up.

Type

float.

Writable

True.

property TapSelector

The tap selector Loadflow parameter to be passed in when setting up.

Type

int.

Writable

True.

property BusLowVoltLimit

The bus lower voltage limit Loadflow parameter to be passed in when setting up.

Type

float.

Writable

True.

property BusHighVoltLimit

The bus upper voltage limit Loadflow parameter to be passed in when setting up.

Type

float.

Writable

True.

property InitialTapPosition

The initial tap position used during Loadflow.

Type

int.

Writable

True.

ClearResults()

Clears all Loadflow results ready for the next Loadflow study. This clears the lists but keeps a reference to the (now) empty list.

GetResultsFromTypecode(ATypecode)

Get the list of results from the typecode provided.

Parameters

ATypecode – The typecode.

SetData(AEracsDataObject)

This method overrides the setter method in TEracsEasy, calls the parent class method, and sets the values of the study properties if HeaderRecords and LoadflowRecords aren’t empty.

Parameters

AEracsDataObject (TEracsData) – The data object to be assigned to the internal Data attribute.

RunCalc()

The main method for running a Loadflow study. RunCalc will run a Loadflow study using the _Data object and the Loadflow object.

ResultsInXml(AXmlObject)

Use this method as a callback function for the OpenInBrowserAsSvg method in TEracsData objects. This method will append all results for Loadflow to the given XML object.

Required

LXML Python library.

Parameters

AXmlObject – The XML object which should be a <results> element, so that <loadflow>…</> results may be appended.

Returns

None, it is appending to the XML object.