I have a Simulink model that connected a main utility (AC-grid) with a three-phase load changing from 20kW to 100kW in 5 seconds and I don't know how to build this load in Simulink. Please your help, will be highly appreciated.
To simulate a varying three-phase load/load profile in Simulink/MATLAB, you can follow these steps:
1. **Open Simulink:**
- Start MATLAB and open Simulink by typing `simulink` in the MATLAB command window.
2. **Create a New Model:**
- Click on "Blank Model" to create a new Simulink model.
3. **Add Power System Components:**
- From the Simulink Library Browser, navigate to the Simscape > Electrical > Specialized Power Systems > Machines and drag a "Three-Phase Programmable Voltage Source" into your model. This will act as the power source.
- Add a "Three-Phase Dynamic Load" from Simscape > Electrical > Specialized Power Systems > Loads.
4. **Configure the Three-Phase Load:**
- Double-click on the "Three-Phase Dynamic Load" block to configure its parameters. You can set the initial active power (P), reactive power (Q), and load variation parameters.
5. **Add a Variable Load Profile:**
- To create a varying load profile, use the "Signal Builder" block from the Simulink Library Browser. You can find it in the "Sources" library.
- Double-click on the "Signal Builder" block to open it. Define your load profile by adding signals that represent the variations in load over time.
6. **Connect the Load Profile to the Load:**
- Use a "From Workspace" block to import the load profile data from MATLAB workspace if you have predefined load data.
- Alternatively, use the "Signal Builder" block directly connected to the inputs of the "Three-Phase Dynamic Load" to provide varying load parameters.
7. **Simulation Configuration:**
- Add a "Powergui" block from Simscape > Electrical > Specialized Power Systems > Utilities. This block is necessary for running simulations involving power systems.
- Configure the simulation parameters by setting the solver type and time step in the "Configuration Parameters" dialog.
8. **Run the Simulation:**
- Connect all the blocks appropriately with the power source feeding into the three-phase dynamic load and the signal builder providing the varying load profile.
- Run the simulation and observe the results using "Scope" blocks or other visualization tools.
### Example: Simulating a Varying Three-Phase Load
Below is an example of a simple Simulink model configuration for a varying three-phase load.
1. **Model Setup:**
- Add a "Three-Phase Programmable Voltage Source" block.
- Add a "Three-Phase Dynamic Load" block.
- Add a "Signal Builder" block to define the varying load profile.
2. **Load Profile Definition:**
- Open the "Signal Builder" block and define a varying load profile (e.g., varying power consumption over a 10-second period).
3. **Connecting Blocks:**
- Connect the "Three-Phase Programmable Voltage Source" to the "Three-Phase Dynamic Load."
- Connect the "Signal Builder" output to the "Three-Phase Dynamic Load" to vary the load parameters dynamically.
- Connect a "Scope" block to monitor the load current or voltage.
Here is a basic script to set up the varying load profile in MATLAB and load it into Simulink:
```matlab
% Define the load profile data
time = [0 2 4 6 8 10]; % Time in seconds
P_load = [100 150 200 150 100 50]; % Active power in Watts
Q_load = [50 75 100 75 50 25]; % Reactive power in Var
% Create a structure to load into the workspace
loadProfile.time = time;
loadProfile.signals.values = [P_load' Q_load'];
loadProfile.signals.dimensions = 2;
% Save the data to the workspace
assignin('base', 'loadProfile', loadProfile);
% Open Simulink and create the model as described
simulink;
```
### Simulink Model Steps
1. **Three-Phase Programmable Voltage Source:**
- Set the parameters for voltage amplitude, frequency, and phase sequence as required.
2. **Three-Phase Dynamic Load:**
- Set initial active and reactive power values, and configure the load variation to use the signals from the "Signal Builder."
3. **Signal Builder Configuration:**
- In the "Signal Builder" block, add two signals for active and reactive power variation over time.
4. **Powergui Block:**
- Add a "Powergui" block for simulation.
5. **Scope Block:**
- Add "Scope" blocks to visualize the voltage and current waveforms.
After setting up and connecting all blocks, run the simulation to observe the varying load profile in action. Adjust the parameters and load profiles as needed to match your specific requirements.
Hello, you have two options, first, using dynamic load, second, you can connected many load by three phase circuit breaker and setting the time on off of the breaker.
Simulating a varying three-phase load or load profile in Simulink/MATLAB involves several steps to ensure the load variations are accurately represented over time. Here's a step-by-step guide:
### 1. Setup Simulink Model
1. **Open Simulink**: Start MATLAB and open Simulink by typing `simulink` in the MATLAB command window.
2. **Create a New Model**: Click on `New` -> `Model`.
### 2. Configure the Three-Phase Source
1. **Three-Phase Source Block**: Add a three-phase source block to your model. You can find it under `Simscape > Electrical > Specialized Power Systems > Sources`.
2. **Configure the Source**: Double-click on the three-phase source block to set the parameters such as voltage and frequency.
### 3. Add a Three-Phase Load
1. **Three-Phase Load Block**: Add a three-phase load block. This can be found under `Simscape > Electrical > Specialized Power Systems > Elements`.
2. **Configure the Load**: Double-click on the load block to set the initial load parameters (e.g., initial power, voltage, and power factor).
### 4. Create a Load Profile
1. **Time-Variant Load**: To simulate a varying load, you can use a `Signal Builder` block, `From Workspace` block, or any other source block that can generate a time-variant signal.
2. **Load Profile Data**: Prepare the load profile data in MATLAB. This could be a set of values that change over time, representing the load variations.
### 5. Connect the Load Profile to the Load
1. **Controlled Load Block**: Use a controlled three-phase load block if available. Connect the load profile signal to the control input of the load block.
2. **Subsystems**: If a controlled load block is not available, you can create a subsystem that modifies the load parameters based on the load profile.
### 6. Simulation Settings
1. **Solver Configuration**: Ensure the solver settings are appropriate for your simulation. Use a continuous solver for better accuracy with power systems.
2. **Run the Simulation**: Configure the simulation time and run the simulation to observe how the load varies over time.
### Example Code for Load Profile
```matlab
% Time vector
time = 0:0.01:10; % 0 to 10 seconds with 0.01s interval
% Load profile (example: a sinusoidal variation)
load_profile = 100 * (1 + 0.5 * sin(2 * pi * 0.1 * time)); % 100 W base load with sinusoidal variation
% Create a timeseries object
load_profile_ts = timeseries(load_profile, time);
% In Simulink, use a 'From Workspace' block to import this load profile
```
### Connecting in Simulink
1. **From Workspace Block**: Drag and drop the `From Workspace` block into your model. Configure it to use the `load_profile_ts` timeseries object.
2. **Connect to Load**: Connect the output of the `From Workspace` block to the appropriate input of your controlled load block or subsystem.
### Example Model
Here is an example of how you might organize your Simulink model:
- **Three-Phase Source** connected to a **Bus Selector**.
- **Bus Selector** outputs connected to a **Controlled Three-Phase Load**.
- **From Workspace** block providing the load profile to the **Controlled Three-Phase Load**.
This setup allows you to simulate a dynamic three-phase load profile in your Simulink model. Adjust the parameters and data as needed to match your specific requirements.
- Badges
- Science topic
- Similar topics
- Filing