Using Optimization in Study Mode

In Study Mode, Optimization uses a wizard approach that steps you through a series of pages to gather input and then presents the results. This allows you to maintain context and easily move backward and forward in the process, as needed.

Optimization allows you to specify a particular loading scenario against which to perform the analysis. Based on the selected load scenario, Optimization uses the real-time load values or load values from the historical load profile for all load points in the analysis area. The user-selectable load scenarios are:

• Real-time loads

• Scaled loads

• Peak loads

• Specific period loads

In addition, you can specify the type of device controls to consider for the analysis.

Based on these settings, the tool generates a plan summary and detailed results for individual feeders, along with any violations or dropped loads. A set of implementation steps is also presented, showing substation transformer tap position changes, capacitor bank status changes, and/or DER real/reactive power output changes. You can save these steps in a new switching sheet or insert them into an open switching sheet.

Note: Optimization uses Web Switching Management functionality and is only available if you are running Web Workspace as the Full Operations plus Web Switching user type. See Understanding User Types and Web Switching Management for more information.

You can use the Optimization wizard to generate a set of steps that can be inserted into a new switching sheet or appended to an existing switching sheet. If you want to add steps to an existing sheet, do the following before you run the optimization tool:

1. Create a new planned switching sheet or open an existing sheet.

2. Click the Record button to enable recording. This is required in order for optimization steps to be appended from the wizard.

Before you run Optimization, select a single device in the Viewer that is connected to the area you want to optimize. The analysis works on a substation bus level and will optimize all feeders fed by the bus. For example, if a substation has two low voltage (LV) buses separated by a normally open switch, the analysis would only optimize devices in the selected bus area. Before you run Optimization, select one or more devices in the Viewer that identify the feeders that you want to optimize. To select more than one device, hold down the CTRL key and click the devices.

Running Optimization in Study Mode

To start Optimization, select a single device that is in the bus area you wish to optimize in the Viewer, and then select the Optimization... option from the Viewer Tools menu. This option is only enabled if a device is currently selected in the Viewer and DMS is enabled in your study session for your user type.

Each screen in the Optimization wizard displays a context pane on the left side of the screen, which shows all the steps in the optimization process. Completed steps are shown in normal text, the current step is bolded, and the remaining steps are grayed out.

The wizard displays the following pages:

• Options

• Load Scenario

• Result Plan

• Summary

The buttons at the bottom of the dialog box allow you to step forward and backward through the process or exit the tool.

Options

Options is the first page of the wizard. It displays the selected device and allows you to specify the basic parameters to use for the optimization.

Options has three sections:

• Objective: allows you to select from the following objectives.

• Return to Nominal: Select this to generate steps to return regulation devices to their nominal regulation settings. The nominal settings are stored in the NMS database and will used in the steps generated by the Optimization tool. The application will attempt to restore any set-points, on/off thresholds, position, or step that would be different from the nominal value. For example, a substation LTC may have two steps to return it to nominal; the first step would be to adjust the voltage target set-point and the second would be to adjust the tap step.

• Loss Minimization: Select this to run Optimization for minimizing losses.

• Conservation Voltage Reduction: Select this to run Optimization for demand reduction. This objective will attempt to reduce technical losses by controlling load tap changer (LTC) tap positions, voltage regulator tap positions, and capacitor bank statuses.

• Power Factor Correction: Select this to run Optimization for power factor correction. This objective will attempt to control capacitor bank statuses to bring the power factor as close to unity as possible.

• Relieve Violations: Select this to run Optimization to relieve voltage and overload violations in the selected area. This objective will attempt to dispatch DERs and control load tap changer (LTC) tap positions, voltage regulator tap positions, and capacitor bank status to reduce violations in the selected area.

Note: DERs will be used only when the DERMS module is licensed.

• Maximize Voltage: Select this to run Optimization to maximize voltage in the selected area. This objective will attempt to increase the average voltage on each feeder within the optimization area by controlling load tap changer (LTC) tap positions, voltage regulator tap positions, and capacitor bank statuses.

• Maximize VAr: Select this to run Optimization to maximize reactive power in the selected area. The objective will attempt to increase the reactive power support within the optimization area by controlling load tap changer (LTC) tap positions, voltage regulator tap positions, capacitor bank statuses, and reactive dispatch at DER units.

• The Controllable Devices list displays the regulation devices that can be optimized.

• The Device Name column displays the controllable device names.

• The Optimize column allows you to select or deselect devices to include in the optimization. By default, optimization is selected for all of the controllable devices.

• The SCADA column indicates whether the device is SCADA enabled or not.

• The Fixed Price column represents the fixed cost to operate the device and is applicable to all types of devices.

• The Utilization Price column is only applicable to DER resources and represents the variable pricing in dollars per MWh.

Load Scenario

The Load Scenario page allows you to change the load profile, scaling factor, and limits. When you click modify, it opens the Power Flow Study Mode Load Scenario window. See “Understanding the Power Flow Study Mode Load Scenario” for details.

Result Plan

The next page of the wizard gives an overview of the analysis results. The information on this page cannot be changed. Use the Plan Details button to display more detailed result data for individual feeders.

• The Summary provides a tabular view of the minimum voltage (%), maximum voltage (%), loading (real/reactive power), real power reduction (%), Power Factor Change, DER Gen output, losses (kW), Power Factor (negative for leading and positive for lagging), and violations/warnings before and after optimization.

Note: The real power reduction (%) will be displayed for Conservation Voltage Reduction/Relieve Violations, the loss reduction (%) will be displayed for Loss Minimization, the power factor change will be used for Power Factor Correction, (%) increase in maximum voltage will be displayed for the Maximize Voltage, and (%) increase in VAr support will be displayed for the Maximize VAr objective.

• The Plan Implementation Steps lists the switching steps required to implement the optimization plan. To target the Viewer to a device affected by a step, select the step and click the View... button.

• The Voltage Distribution on Affected Feeders graph displays the voltage distribution on affected feeders before (in gray) and after (in blue) changes are made.

• Click Plan Details... to view results.

Plan Details

When you select a feeder from the Feeders list on the top of the page, the following details are shown:

• Violations tree table shows any violations associated with the selected feeder. To see the device associated with the violation, select a violation in the Feeder Violations list and click View.... (This button is enabled whenever a violation node is selected.)

• Voltage Profile Graph for the selected feeder. To see the graph, select the tab Voltage Profile graph in the tabbed pane. This graph shows the relationship of load voltages as a function of distance from feeder start point before and after the optimization steps are implemented. This is useful for seeing how voltage drops, and how close load points are getting to their voltage limits.

• Voltage Distribution Graph for the selected feeder. To see the graph, select the tab Voltage Distribution graph in the tabbed pane.

Summary

The Summary page displays the implementation steps for the plan.

To save these steps in a new switching plan, click the Create Plan... button. The Optimization wizard closes, and a new planned switching sheet opens in the Web Switching Management window.

To insert these steps into a currently open switching sheet, click the Append Steps... button. The steps are inserted into the open sheet in the Web Switching Management window.

See “Planned Switching” for more information about Web Switching Management.