The main five types of solar charging controllers

- Jan 12, 2019-

The main five types of solar panel photovoltaic charging controllers


1, parallel controller


When the battery is full, the parallel controller uses electronic components to shunt the output energy of the PV array to internal parallel resistors or power modules, and then consumes it in the form of heat. Because this method consumes thermal energy, it is generally only used in small low-power systems, and has the following requirements for shunt loads:


1 DC shunt load current must not exceed the maximum rated current of the controller.


2 The voltage level of the DC shunt load must be higher than the maximum battery voltage.


3 DC shunt load must have a rated power of at least 150% of the maximum PV array output power.


The wire and overcurrent protection of the DC shunt load circuit must be at least 150% of the maximum rated current of the controller.


These types of controllers do not have mechanical components such as relays, so they work very reliably.


2. Series controller


The series controller uses the machine core to control the charging process and cut off the faster array at night, which is generally used in higher power systems. The capacity of the relay determines the power level of the charge controller.


3. Pulse width modulation controller


The pulse width modulation controller cuts/turns on the input of the PV array in PWM pulse mode. When the battery tends to be full, the frequency and time of the pulse is shortened. This charging process can form a relatively complete state of charge, which can increase the total cycle life of the battery in the photovoltaic system.


4. Intelligent controller


The intelligent controller adopts a single-chip microcomputer with CPU to perform high-speed real-time acquisition of the operating parameters of the photovoltaic system, and cuts the wine control of the single or multi-channel photovoltaic array by a software program according to a certain control law. The system can also perform remote high control through the RS-232 interface of the single-chip microcomputer and the pre-modulation demodulator.


5. Maximum power tracking controller


The maximum power tracking controller multiplies the voltage and current of the solar panel to obtain the power, and then determines whether the output power of the solar panel reaches the maximum at this time. If the power is not operated at the maximum power point, the pulse width is adjusted, and the modulation output accounts for the ratio is changed, the charging current is changed, the real-time sampling is performed again, and a judgment is made as to whether or not the duty ratio is changed. Through this optimization process, the solar panel square array is always operated at the maximum power point to make full use of the energy output. At the same time, the PWM modulation method is adopted to make the charging current become a pulse current to reduce the polarization of the battery and improve the charging efficiency.