The answer to this is to add a Bypass Diode bias bias in parallel and with a polarization opposite to the solar cell. In the normal state of the cell, the bias is direct, as a result of the bias bias, the bias is inverted and no flow passes. If the cell is reversed due to a short circuit in the short circuit, the bi-directional diode will be biased directly to direct the current. As a result, the “bad” double-headed voltage drop is just as large as the diode voltage, thus preventing high energy loss and hot spot heating. A biased diode is used for a group of cells (usually between 10 and 15 cells). For example, for a panel with 36 cells, 3 and sometimes 2 bipod diode will be inserted. All manufacturers do not necessarily use the BIOS. In this case, care must be taken not to put the panel under short conditions for long periods of time and to prevent the shadow of buildings, trees or other panels on it.
Solar controller charge
Charging the solar controller is another solar system equipment that coordinates the DC power generated by the solar panels to the DC power supply suitable for entering the battery. To better understand this, solar panels usually produce higher voltages than batteries, and charging solar controllers should convert these higher voltages to a low voltage level to feed the batteries.
For example, solar panels with a power output of 150 watts are 12 volts, but this voltage is merely a number on paper and the actual voltage of these panels is between 16 and 18 volts. On the other hand, the 12 volt battery does not have a true 12 volt voltage. In fact, their voltage is between 10.5 and 7.27 V, depending on the charging status. Most batteries require a voltage of 2.13 to 4.14 V to complete charging, which is different from the output voltage of solar panels.
Therefore, the charge of solar controllers in isolated systems of the solar network is critical to adjusting the output voltage of the panels and the input of the battery, which increases the battery life and improves the performance of the entire system.
PWM: Pulse Width Modulated
A summary of the 3 words above, which is the literal meaning, is the switching and switching of the power on and off at a given time interval and as needed. Now, if we want to define the charge of the solar controller, it means that it will connect the panel and battery intermittently and alternately, and actually act like a smart key, which will allow it to charge and discharge more. It prevents the battery from falling short.
MPPT: Maximum Power Point Tracking
As its name implies, this charge is the controller’s maximum power follower. This means that they receive the highest voltage output from the panels and deliver it to the desired voltage level of the battery. At different times of day and in different situations of solar panels, these panels have a definite instantaneous power, which is the voltage of the panels, multiplied by the flow of panels. Now, if we divide the voltage over the current, the internal resistance of the panels at that instant is obtained for the specified amount of radiation of the sun. According to the basic rules of the circuit, in order to transmit the maximum power to the load, the load resistance must be equal to the resistance of the other parts of the circuit. Because the sun moves throughout the day, the radiation intensity is variable and the voltages and voltages of the panels are also variable.
When charging mppt controllers using advanced algorithms and more sophisticated electronic components, the maximum output power from panels can be obtained in comparison with the pwm chargers.
Advantages and Disadvantages:
Their price is very affordable. Approximately one-third of the mppt charging controllers
They can be used in a wider range and are used for a longer time.
Have a smaller size.
They are less durable due to the lack of electronic components and lower sensitivity.
The nominal bank voltage of the battery and the nominal voltage of the panel should be in exactly the same amount, so the design of the systems is more sensitive to pwm.
They are not compatible with 60-cell panels.
Increased productivity by up to 30%
The ability to extract more voltages from solar panels and their controlled injection into batteries
Possibility to supply at a higher level – up to 80 amps
Better performance in cooler weather
Compatible with 60-cell panels
The price is 3 times the charging price of the pwm controllers.
Their size is larger than the pwm chargers.
Lifespan due to having more electronic components and more sensitive.
Charging the battery by charging the controller:
stage 1: BULK
At this stage, the battery is usually over 80% empty and the controller charge allows the maximum amount of outlet flow from the panel to enter the battery, and then the voltage goes up slowly.
stage 2: Absorb
At this point, the battery charge has reached its ideal size and is approximately 80 to 90 percent complete. The Absorb or Absorb Voltage for 12 volt acid batteries ranges from 14.4 to 8.14 volts. During this stage, the battery has its own scheduled nameplate voltage and stopping the flow from the panels to prevent over charging and damage to the batteries.
Stage 3: Float
After reaching the Absorb or Absorb Voltage, the planned battery life is 100% charged and the battery charge is adjusted to its nominal value. Adjustment of the controller’s charge correctly plays a significant role in improving system performance.