Design and Implementation of Smart Control on a Texas Instruments (TI) Delfino Microcontroller for a Photovoltaic System
Pakistan continues to face power shortages in the access of at least 4000 MW, and this shortage increases as the demand for the power grows. The power shortage is because of higher power demand, and because of transmission losses in the distribution lines as the power generated is delivered to far o
2025-06-28 16:31:44 - Adil Khan
Design and Implementation of Smart Control on a Texas Instruments (TI) Delfino Microcontroller for a Photovoltaic System
Project Area of Specialization Electrical/Electronic EngineeringProject SummaryPakistan continues to face power shortages in the access of at least 4000 MW, and this shortage increases as the demand for the power grows. The power shortage is because of higher power demand, and because of transmission losses in the distribution lines as the power generated is delivered to far off areas using these lines. One possible solution to the power shortage problem is to take advantage of solar power. Solar power is free, and is a good alternative owing to its pollution-free nature, one-time installation and low maintenance cost. Solar power is particularly suitable for Pakistan as it gets increased exposure to the sun throughout the year.
Most of the recently merged areas (formerly known as Federally Administered Tribal Areas) and some areas in northern Khyber Pakhtunkhwa are away from the National Grid. Connecting these areas to the National Grid will not be easy as it requires the transmission lines have to be laid first which require a huge capital cost. If small Photovoltaic (PV) power generation systems are established in the areas needing electric power, there will no need for the transmission lines too, thus reducing the cost and the losses in the system.
The purpose of the work is to propose a PV system with greatly improved efficiency and a cloud-based ‘smart’ control system.
The proposed PV system consists of the following three sub-modules,
a) High-Voltage (HV) High-Power (HP) power converters to generate 220V AC voltage from the DC power extracted from the PV panels
b) Embedded system to control the power converter as well as extract maximum power available from the PV panels
c) Cloud-based system for remote telemetry and control of the PV System
The scope of this project is to design a ‘smart’ embedded system for the PV system. In this project, a Texas Instruments (TI) Delphino Microcontroller (TMS320F28379D) is used to implement the above embedded system. NodeECU ESP-8622 Wifi module, SIM900A GSM module and HC-05 Bluetooth module are used to have two-way communication between the embedded system, User and Cloud.
Project ObjectivesThe power converters in the PV system take the DC power from the PV panels and converts it into AC power. It can also charge Low-Voltage (LV) batteries. There are three power converters in the PV system. The first one is responsible for extracting maximum available DC power from the PV panels, and converts it into HV DC voltage. The second power converter is responsible for charging the LV batteries. The last power converter is responsible for converting the HV DC into AC power. All these three power converters need embedded systems to generate PWM signals and to implement the controllers. These embedded systems are acting as the brain of the PV system.
The main objectives of this project are to,
i) Implement a Maximum Power Point Tracking (MPPT) algorithm to extract the maximum power from the PV panels
ii) Generate Pulse Width Modulation (PWM) signals for the semiconductor switches in the HV HP power converters in a special sequence to regulate the output voltage and power of these power converters.
iii) Read the voltages and currents sensors reading and convert them in digital signals using the Analog-to-Digital Converters (ADCs).
iv) Implement the PID controllers to regulate the output voltage and power in the power converters.
v) Have a two-way communication with the Cloud via Wifi and GSM modules. The sensors data is sent to the Cloud for data logging, telemetry and debugging purposes. It can also accept the control signals and system configurations from the Cloud.
vi) Have a two-way communication with the User via the Bluetooth module. The sensors data is sent to the User for telemetry and debugging purposes. It can also accept the control signals and system configurations from the User.
Project Implementation MethodThe hardware for the embedded system consists of,
a) Texas Instruments (TI) Delphino Microcontroller (TMS320F28379D) Launchpad
b) Communication Modules (NodeECU ESP-8622 Wifi Module, SIM900A GSM Module and HC-05 Bluetooth Module)
The TI Delphino microcontroller has a number of sub-modules optimized for power converters applications. In this project, the following sub-modules of this microcontroller will be used,
i) High-Resolution (HR) PWM sub-module
ii) Analog-to-Digital Converters (ADCs)
iii) Communication ports (I2C, SPI, UART and CAN)
The closed-loop control system consisting of digital filters and PID controllers can be implemented very easily using this microcontroller. The firmware can be reprogrammed very easily via a USB interface with a PC. TI website has a lot of help available on the above sub-modules.
Project Implementation Stages:
1) Simulations:
The HV HP components and the embedded system for the power converters are developed in parallel. These power converters are first simulated in PSIM software to obtain the dummy data for the ADC and PWM. The simulation results give the upper and lower limit for the PWM frequencies, duty-cycles and phase-shifts. It also provides the waveforms of the sensed data.
2) Firmware Development with ‘Dummy’ Data:
The initial firmware for the power converters is developed using the ‘dummy’ data and the examples available on the TI website. Function generators are used to generate the sensor data and the ADCs are used to measure these signals. The PWM signals generated by the microcontroller are measured using a digital oscilloscope and are compared to the simulation results. In this way, the initial firmware is developed.
3) Firmware Testing in Real Hardware at Low Output Power:
After building the actual HV HP power converter, the developed embedded systems with the initial firmware is used to drive them. The sensor measurements are recalibrated. The PWM signals are also tested at very low output power. The communication modules are also tested at this stage. In this way, the initial firmware is validated at low output power.
4) Firmware Testing at Full Voltage and Full Load:
After validating the firmware at low power, the output power is increased in small steps. The overall system is tested with many real-world scenarios like shading conditions on the PV panels and variations in the output load. With all these tests, both the hardware and software designs are validated.
Benefits of the ProjectThe benefits offered by the designed PV system are,
i) It is indigenously developed.
ii) It has higher end-to-end power efficiency as compared to the PV systems available in the market
iii) It is compact, has a longer life and lower cost as compared to the PV systems available in the market
iv) It is ‘smart’ in the sense that after detecting the shading on the panels, it can alert the user to reduce the load
v) With special system-level control strategies, the PV system can support temporary overload conditions during the daytime by getting the power from the LV batteries. This feature is currently not available in the commercially available PV systems.
vi) It has a Cloud-based telemetry and control system. With this feature, the PV system can be monitored and controlled from anywhere in the world.
vii) With this project, a state-of-the-art research facility has been established where the students conduct research in Renewable Energy Systems.
Technical Details of Final DeliverableThe end product of this project is a 1kW prototype PV system for residential applications. The designed system will have three power converters capable extracting maximum power from the PV panels, charging LV Batteries, and providing AC power.
The target end-to-end power efficiency is more than 75%. This system will be able to send telemetry data to the Cloud (via GSM and Wifi modules) and to User (via Bluetooth module). It will be able to receive configuration setting from Cloud (via GSM and Wifi modules) and from User (via Bluetooth module).
Final Deliverable of the Project HW/SW integrated systemCore Industry Energy Other IndustriesCore Technology Cloud InfrastructureOther TechnologiesSustainable Development Goals Affordable and Clean Energy, Climate ActionRequired Resources| Item Name | Type | No. of Units | Per Unit Cost (in Rs) | Total (in Rs) |
|---|---|---|---|---|
| Total in (Rs) | 80000 | |||
| Microcontroller Boards | Equipment | 8 | 7000 | 56000 |
| Sensors | Equipment | 10 | 1400 | 14000 |
| Surveying and Traveling | Miscellaneous | 2 | 5000 | 10000 |