A solar charge controller (also known as a solar regulator) is one of the key components of a solar installation. It is located between the solar panel and the battery storage system, mainly obtaining energy from the solar panel and converting it to the optimal voltage, ensuring that the current flows into the battery in a controlled manner.
In recent years, due to the advances in lithium battery technology, in terms of energy density, lighter weight, long cycle life, low self-discharge power, etc. are welcomed by the market, lithium batteries are widely used in solar energy devices, in order to maximize the utility and service life of the lithium batteries, solar charge controllers have become critical. Solar controllers are categorized as follows according to function and mode:
Ordinary solar charge controllers are mainly used in photovoltaic power generation systems mainly applied to daily management and monitoring.
Chargeable solar charge controller mainly for battery charging and protection functions, applicable to small solar lighting system, remote communication, etc..
Integrated solar controllers, with both charging and discharging functions, are suitable for large solar modules and battery systems, which are more convenient for us to use.
Charge-discharge type solar controller is a combination of charging and discharging functions into one, mainly applicable to some low-power solar products.
Charging control is realized through pulse modulation technology, so that the solar panel voltage is just higher than the charging voltage, which is mainly used for smaller systems with lower cost.
Charging control is realized through maximum power point tracking technology, specifically, the voltage of the solar panel is lowered to the voltage used by the battery, which can utilize the energy produced by the solar panel more effectively.
Conventional low-voltage disconnection mode is when the charging voltage reaches the set value, it will automatically cut off the battery to avoid overcharging and play a role in protecting the battery.
Voltage protection mode is when the voltage is lower than the set value, it will automatically cut off the load to prevent the battery from deep discharge, which will cause harm to the battery.
The most suitable solar charge controller for Li-ion battery is MPPT type solar charge controller, MPPT type solar charge controller is a modification of PWM type, which is very suitable for complex solar control system, and it is the best choice for Li-ion battery. MPPT type solar controller regulates the current and voltage of the solar panels through the use of complex algorithms and can adjust the resistor to find the maximum point of the power output (the maximum point of the power output is based on the solar panel’s current and voltage), the power output of the solar panels can be adjusted to the maximum point of the power output. The maximum power output point is adjusted according to the characteristics of the solar panels, weather and temperature), and by tracking the maximum power point, it ensures that the solar charge controller is always in the best working condition.
Solar charge controllers are mainly used to charge batteries with solar energy and provide load control voltage devices for voltage sensitive equipment. Solar charge controllers can prevent overcharging and undercharging of batteries, and in some cases even reverse the current to prevent current depletion, ensuring optimal battery health and performance, and are the core control part of the entire photovoltaic power system.
For small systems with fewer solar panels, it is recommended to choose PWM type solar charge controllers, which are cheaper to use. MPPT solar charge controllers are more suitable for systems above 200 watts to ensure maximum benefits.
We should pay attention to the safety performance, because solar controllers can also fail, we should pay attention to the short-circuit protection, reverse polarity protection and overcharge protection and other safety features, to protect our personal life and health safety and the safety of solar energy equipment.
PWM solar controllers are cheaper than MPPT solar controllers, but this should be combined with our personal needs, personal budget, the size of the solar system, and so on, to choose the most suitable solar controller for us.
Because some solar energy controllers have different functions, with temperature compensation function or remote monitoring function, we can keep a close eye on the operation status through our smart devices to ensure safety.
According to the location where you live to install the solar energy system, the local climate environment will affect the operation condition, if the local climate has a large influence factor on the solar panel, it is recommended to choose MPPT solar charge controller. If the climate environment has less influence on the solar panel, you can choose PWM solar controller.
Lithium batteries need to be MPPT type solar controller, which is combined with the characteristics of lithium batteries comprehensive consideration of the results, if you want to buy a solar controller need to consider the above factors, choose the most suitable for their own batteries.
