In the constant pursuit of improving the efficiency and quality of electrical systems, monitoring tools become essential.
With this purpose in mind, we have introduced a new widget plugin that illustrates the "Four-Quadrant Diagram" of electrical power, identifying the correct flow of active and reactive power within our electrical system. The purpose of this tool is to visualize energy consumption and injection into the grid, in addition to monitoring the power factor of our system in each quadrant and preventing potential penalties for energy ranges outside of standards.
Requirements
Ubidots account (trial or licensed).
One device measuring electric variables, including active and reactive power.
1. What's a four-quadrant diagram?
The four-quadrant diagram is a graphical representation with two axis (P and Q) and four sections that helps to visualize and analyze the relationship between active, reactive and apparent power in an electrical alternating current (AC) system.
Active power (P): Is useful power that does some real work, expressed in Watts (W).
Reactive power (Q): Is the power, measured in Volt-ampere reactive (Var), released and stored by capacitors and inductors, affecting the power factor of a system.
Apparent power (S): Is the total power available in an electric system, expressed in Volt-ampere (VA). A combination of active and reactive power.
Each quadrant within the diagram corresponds to either a capacitive or inductive (positive or negative) load. Furthermore, each quadrant provides detailed insights into our system, offering valuable information for comprehensive analysis.
The horizontal axis corresponds to active power (P) and its position on the plane can be either negative or positive.
The vertical axis corresponds to reactive power (Q) and its position on the plane can also be either negative or positive.
In addition to vectors P and Q, the vector S is displayed, representing the apparent power of the system, which is calculated from P and Q's data using the following expression:
NOTE: In the configuration of the plugin, you can customize the message you want to display in the widget according to the position of active and reactive power vectors on the map.
2. Device configuration
To ensure proper utilization of the plugin, it's essential to include at least the following two variables in your device configuration.
NOTE: Consider that the diagram exhibits vectors only when the two associated variables (active and reactive power) possess values with the same timestamp. Therefore, if data is sent for only one of the variables, the diagram will not plot the vectors. Instead, it will present a message indicating this situation, as illustrated in the following image:
3. Creating a Power Diagram plugin
Step 1. In your Ubidots account, go to the "Devices" tab, click on "Plugins", and then click on the "+" button to create a new plugin. Look for the Power Diagram, click on it, and follow the steps shown in this GIF:
Step 2. After reading the plugin's description and moving onto the next step, you must select the desired Ubidots token to create the plugin.
Step 3 (Optional). You can customize the name of your plugin and its description.
4. Configuring widget input data
To use the widget in any of your dashboards, simply click on the "+" button and scroll down to the "plugin" section. There, you will find the Power Diagram widget ready for selection. Click on it.
In the widget's settings, you will be able to change the following fields:
Active power: API label of the device's active power variable.
Reactive power: API label of the device's reactive power variable.
With these two variables, the widget will calculate the power factor, Phi angle, and the apparent power (S) to display the vectors on the corresponding quadrant.
Quadrant messages: Enter the message to be displayed on the widget when the calculated apparent power corresponds to each respective quadrant.
Here's a set of sample messages that you can add in each message field:
First quadrant message: Active and reactive power consumption.
Second quadrant message: Auto-generation and consumption of reactive power at the load.
Third quadrant message: Auto-generation and export of reactive power.
Fourth quadrant message: Consumption of active power and capacitive reactive power at the load.
NOTE: Currently, the Power Diagram widget is only supported in dynamic dashboards.
5. Visualization
Once you've finished configuring the widget and inputting your custom messages for each quadrant, the widget will perform its calculations and showcase the respective vectors for P (active power), Q (reactive power), and S (apparent power) on the diagram.
NOTE: Currently, the Widget Plugin feature only supports "last value" as aggregation method. Additionally, it does not offer support for time spans other than the one selected in the dashboard's date picker.
