pwm solar controller and tracker - energy storage devices

Pwm solar controllers and trackers photovoltaic applications can be grouped according to the scheme of interaction with the grid: grid-connected, independent, and hybrid.
Photovoltaic system by photovoltaic generator (
Units, modules and arrays)
Energy storage device (
Battery, for example)
, AC and DC consumers and power adjustment elements.
The most common method is to use photovoltaic cells in the grid.
However, in order to understand the performance of photovoltaic cells and maximize their radiation efficiency, independent photovoltaic cells have aroused some interest, especially in the field of solar tracker systems.
Over the years, testing and researchers have demonstrated that the development of smart solar trackers maximizes the generation of energy.
In this competitive world of advanced scientific discovery, the introduction of automation systems improves existing power generation methods.
Prior to the introduction of the solar tracking method, fixed solar panels were positioned in a reasonable tilt direction, depending on the location.
In the system, the tilt angle depends on a slight winter or summer deviation.
The photovoltaic system will face the "real north" of the Northern Hemisphere and the "real south" of the Southern Hemisphere ".
Solar tracking is the best when tracking the tilt angle of the photovoltaic system in sync with the seasonal changes in the sun's height.
Several methods of solar tracking systems have been investigated and evaluated to keep photovoltaic cells perpendicular to the solar beam.
The ideal tracker will allow the photovoltaic cells to point to the Sun, compensating for two variations in the solar elevation angle (
All Day)
Latitude offset of the Sun (
Period of seasonal change)
Change of azimuth.
In view of this, there are two main types of sun trackers: passive (mechanical)and active (electrical)
One category of passive solar trackers is fixed solar panels.
It is placed horizontally on a fixed ground facing the sky.
However, most passive solar trackers are based on manual adjustment of panels, thermal expansion of shape memory alloys made of aluminum and steel or two metal strips.
Typically, this tracker is made up of a pair of actuators that work with each other, which are balanced through equal lighting.
Through the differential illumination of the actuator, the unbalanced force is used for the positioning of the equipment in such a direction, in which the balance of the equal illumination and force of the actuator is restored.
Another passive tracking technique is based on the mass imbalance at both ends of the panel.
This tracker does not use any electronic controls or motors.
Two identical cylindrical tubes are filled with fluid at Split pressure.
The sun heats the fluid, resulting in evaporation, moving from one cylinder to another, which creates a mass imbalance.
Compared with the active tracker, the passive solar tracker is less complex but less efficient.
Although the passive tracker is usually low in price, it has not yet been widely accepted by consumers.
On the other hand, the main active tracker can be classified as a microprocessor-based computer
Based on the date and time of the control, the auxiliary double-sided solar cells, and the combination of these three systems.
In a microprocessor-based solar tracker system, the controller is connected to a DC motor or a linear driver, also known as a super Jack.
Once the position is selected, the range of orientation elevation is determined and the number of angle steps is calculated.
Typically used to monitor power generation, they also connect this tracking device to a PC by code written in assembly or picbasic.
Sensors are often used in this solar tracker design.
For example, a photo
The resistor is placed in a dark box with a small hole at the top of the box to detect the lighting, and one called light-
Related resistance (LDR)
Indicates the intensity of radiation (
When the light shines on it, its resistance changes from several thousand ohms in the dark to only a few hundred ohms).
The micro-controller then captures the signal and the micro-controller provides the signal of the rotating panel to the motor.
In this design, unreliable and expensive components such as batteries and drive electronics are completely eliminated.
So it is a very simple and reliable solar tracker for space and ground applications.
On the other hand, the method uses the method of combining the microprocessor with the sensor and the date/time-based system, and the sensor (such as the optical sensor) sends the signal to the microprocessor.
Using a real-time clock (RTC)
, The tracker calculates the position of the Sun based on the date/time information of its clock.
The data collected during the day is analyzed and a new set of improved parameters for installation errors are calculated.
The second Angel uses this data to calculate the more accurate position of the sun, and this cycle will continue.
In this solar tracking system that we are designing, the required position is pre-calculated and programmed into programmable logic control (PLC)
This term controls the motor to adjust the panel to maintain a position perpendicular to the sun.
After selecting solar panels and other components, the overall structural design of the solar tracker was made.
The solar tracker weighs 10 kg and the overall size is 1480mm x 680mm x 30mm.
The proposed solar tracker is compact enough to enable it to be installed on the wall.
It consists of a PV panel, a linear drive (also known as a super Jack;
The motor and electronic plate bracket and the vertical column with the base plate bracket.
The whole structure is made of metal plates.
The pillar maintains a panel alignment ratio of 48: 100 in order to gain better flexibility during the panel jack-up.
The tracker is designed to be a singleaxis rotation (East to West)
The installation method of the Super Jack makes the tracker system only have one-
Degree of freedom of axis rotation.
The fixture used to fix the sensor is then assembled at both ends of the PV panel and aligned to sense solar irradiance.
The PV panel frame bracket has a support bar that runs through the width of the PV panel.
Integrate the entire mechanical and electrical subsystem into the solar tracker system as shown below.
The solar tracker system is mainly composed of electrical components.
Photovoltaic cells, LDR sensors, leads-
Acid battery, a voltage tracking control board based on pic f72.
The LDR sensor senses the sunlight intensity and sends the signal to the micro-controller to move the PV panel through the Super Jack.
The electrical energy is then stored in the lead
Acid batteries later used to power their respective home devices.
Photovoltaic cells are a device that converts solar energy into electric energy.
The selected solar panel is capable of generating 130 W at maximum power of 17 V max. 6V.
Calculate the charging amplifier [CURRENT]
Power = voltage * Current Where: power = 130 w Voltage = 17.
6 v current =?
Current = 130/17.
6 Current = 7.
We need 12.
6 v power supply, up to 10 can be processed. 32A.
Detect battery voltage using in-detect and track controller
Construction analog-to-digital converter (ADC)
To prevent excessive
Charge the battery.
LDR sensor (NORPS-12)
Basically resistance, when exposed to irradiance, they change the resistance according to the intensity of the sun.
The output of the sensor circuit is the analog voltage used as the input of the PIC microprocessor.
In order to determine the value of the resistance R, various values of different resistors are checked to finalize the appropriate resistance.
The required resistor value should provide voltage covering sunny and cloudy conditions.
According to the self-experiment, the value of the resistor as shown below.
From the experimental results, it is found that changing the value of the resistance in the voltage divider circuit helps to improve the sensitivity of the output.
The resistance of 100 Ω was found to be suitable for distinguishing sunny days from cloudy days. Fixed resistance (Ω)
Vout on a sunny day is Vout 50 2 on a cloudy day. 14 0. 82 1. 32 100 3. 95 0. 90 3. 05 200 4. 56 1. 35 3. 21 500 4. 78 1. 41 3. 37 1000 5. 01 1. 89 3.
The drive mechanism includes a super Jack and two 12 v relay switching systems.
Control the super Jack mainly using the micro controller (16f72).
The controller uses a high-low signal to drive the Super Jack through two 12 v relays, and the control speed corresponds to 12 v-
15 v power supply from solar panel. . .
The solar charging and tracking controller regulates the voltage and current of the solar panel located between the solar panel and the battery.
It is used to keep the proper charging voltage on the battery.
When the input voltage of the solar panel rises, the charging controller adjusts the charging of the battery to prevent any overcharging.
Charging Controller type: 1. ON OFF 2. PWM 3.
The most basic charging controller (ON/OFF type)
When the battery voltage rises to a certain level, just monitor the battery voltage and turn on the circuit to stop charging.
Of the three charging controllers, the most efficient point tracking is the highest, but the cost is high, requiring complex circuits and algorithms.
So thinking that the PWM charging controller is the best for us, it is seen as the first major step forward in solar battery charging.
Pulse Width Modulation (PWM)
Is the most effective means to achieve constant voltage battery charging by adjusting the duty cycle of the switch (MOSFET ).
In the PWM charging controller, the current of the solar panel is gradually thinner depending on the battery condition and charging demand.
When the battery voltage reaches the adjustment setting point, the PWM algorithm slowly reduces the charging current to avoid the heat and gas of the battery, however, charging continues to return the maximum energy to the battery in the shortest time.
Advantages of PWM charging controller: 1.
Higher charging efficiency 2.
Longer Battery Life 3.
Reduce the battery when heating.
The ability of the battery to clutter.
The MCU target board is used to control the 12 v DC power jack in the system.
It receives signals from the LDR sensor.
Convert the analog voltage to a digital signal (logic 1 or 0)for processing.
The processor is a pic f72 from microchips.