MPPT Solar Controller Overview, Principles, Functions
Overview of MPPT
The MPPT system is an electrical system that enables the photovoltaic panel to output more power by adjusting the working state of the electrical module, and can effectively store the direct current generated by the solar panel in the storage battery, which can effectively solve the problem that the conventional power grid can not be covered. Living and industrial electricity in remote areas and tourist areas do not cause environmental pollution.
Photovoltaic cell output power andMPPT controllerThe operating voltage is related to its output power only when it is operating at the most suitable voltage.
The sunshine intensity is 1000W/down, U=24V, I=1A; U=30V, I=0.9A; U=36V, I=0.7A; the output power is maximum under the voltage of 30.
The principle of MPPT
To charge the battery, the output voltage of the solar panel must be higher than the current voltage of the battery. If the voltage of the solar panel is lower than the voltage of the battery, the output current will be close to zero. Therefore, for safety reasons, the solar panel has a peak voltage (Vpp) of about 17V when it is manufactured, which is set at a standard temperature of 25 °C. When the weather is very hot, the peak voltage Vpp of the solar panel will drop to about 15V, but in cold weather, the peak voltage Vpp of the solar energy can reach 18V.
The traditional solar charge and discharge controller is a bit like a manual gearbox. When the engine speed increases, if the gear position of the gearbox does not increase correspondingly, it will inevitably affect the speed. However, for the traditional controller, the charging parameters are set before leaving the factory, that is, the MPPT controller will immediately track the maximum power point in the solar panel to exert the maximum efficiency of the solar panel. The higher the voltage, the more power can be output through the maximum power tracking, thus improving the charging efficiency. In theory, the solar power system using the MPPT controller will increase the efficiency by 50% compared with the traditional one. However, according to our actual test, the final efficiency can be increased by 20%-30% due to the surrounding environment and various energy losses. . In this sense, the MPPT solar charge and discharge controller is bound to eventually replace the traditional solar controller.
MPPT function
MPPT controllerMain function: Detect the DC voltage and output current of the main circuit, calculate the output power of the solar array, and track the maximum power point. The disturbance resistor R and the MOSFET are connected in series, and the average current through the resistor is changed by changing the duty ratio of the MOSFET under the condition that the output voltage is substantially stable, thereby generating a disturbance of the current. At the same time, the output current and voltage of the photovoltaic cell will also change accordingly. By measuring the change of the output power and voltage of the photovoltaic cell before and after the disturbance, the disturbance direction of the next cycle is determined, and when the disturbance direction is correct, the output power of the solar energy panel increases. The cycle continues to perturb in the same direction, and vice versa, in the opposite direction, so that disturbances and observations are repeated to maximize the output of the solar photovoltaic panel.
Disclaimer: The content is partly from the internet. In order to pass on more information, it does not mean agreeing to its views or confirming its description. Article content is for reference only. If there is any infringement, please contact in time.
