Generator assignments to WeatherStation and XYCurve

The ability add weather-dependent limits was added in Version 23.

Generator objects have various field associated with them which are used as part of the Weather-Dependent Limits which are accessed on the Weather-Dependent Limits dialog.

There also similar weather-related fields for Substation and Branch objects.

Generator Weather-Related Fields

Each Generator can be assigned to a WeatherStation object directly by entering the Name of a WeatherStation object in the branch field WeatherStation. Setting the WeatherStation field to a blank string will remove any existing WeatherStation designation. This WeatherStation will be used for all weather related values for the Generator. If the WeatherStation is not specified for a generator, then the generator will look at the terminal bus substations WeatherStation instead.

The generator object also has fields to specify a list of XYCurves that describe the temperature-dependent MW limits. See the topic XYCurve, XYCurvePoint, XYCurveX Objects for more details on how to define XYCurves. There are entries for specifying XYCurves for use for MWMax limits and also an entry for a list of XYCurves for MWMin limits. There are YES/NO fields to designate whether these XYCurves should be used. Finally, for generators there is also a field to specify which field to use as the x-value when performing lookups using the XYCurves. For example, for a wind power plant, using WindSpeedMsec (meters per second) may make the most sense, while for a solar power plant the InsolationPerc may be more useful.

These fields are described in the following table.

Field	Type	Type
WeatherStation	String	WeatherStation object to which the user has assigned the substation
WeatherMWMaxUse	String	YES or NO. Specify YES to use the TemperatureLimitNormal values
WeatherMWMinUse	String	YES or NO. Specify YES to use the TemperatureLimitCTG values
WeatherMWMaxName WeatherMWMinName	String	A comma-delimited list of names of XYCurves that will impact this Generator. Multiple curves are allowed because there may be multiple devices that impact the limit. The limit that is calculated by PowerWorld Simulator will be the minimum limit across all these curves. The x value of the curves is used is determined by the field WeatherMWMaxField and WeatherMWMinField
WeatherMWMaxField WeatherMWMinField	String	Field indicating what X value is represented in the XYCurves and which weather Station value should be used to determine the MWMax limit. Options are: TempF, TempC, DewPointF, DewPointC, CloudCoverPerc, WindSpeedmph, WindDirection, WindSpeedKnots, WindSpeedMsec, WindSpeedkmph, and InsolationPerc.
WeatherMWMax WeatherMWMin	Single Float	Uses the specified WeatherMWMaxField or WeatherMWMinField value to determine the X-value to use as a lookup into the XYCurves of WeatherMWMaxName and WeatherMWMinName. Looks up the MW limits based on the list of Limit XYCurves specified. If no curves are specified, then value is blank If 1 curve is specified, then value returns the lookup for that curve If multiple curves, then value performs the lookup on all curves and then returns the minimum value across all the MAX curves. (For the WeatherMWMin it would return the maximum value across all the MIN curves.
WS_TempF WS_TempC WS_DewPointF WS_DewPointC WS_CloudCoverPerc WS_WindSpeedmph WS_WindSpeedKnots WS_WindSpeedMsec WS_WindSpeedkmph WS_WindDirection WS_InsolationPerc WS_Humidity WS_WindChillF WS_WindChillC WS_HeatIndexF WS_HeatIndexC	Single Float	The various Weather Measurement values stored with a WeatherStation. If a WeatherStation is specified then this weather station's value is used. If a WeatherStation is not specified, then the terminal bus substation WeatherStation is used.