Overview of solar photovoltaic controllers
The solar controller is an important component of the solar photovoltaic system, an electronic device that can automatically prevent the battery pack from being overcharged and overdischarged and has a simple measurement function. Since the battery pack is overcharged and will seriously affect its performance and life, the charge and discharge controller is generally essential in photovoltaic systems. It largely determines the reliability of solar photovoltaic systems. The characters of the controller are mainly to realize the charging of the battery by the solar energy and protect the battery in the photovoltaic system.
Principle of solar photovoltaic controller
Single parallel type charge and discharge controller:
The switching device T1 in the charging circuit of the parallel type charge and discharge controller is connected in parallel to the output terminal of the solar cell array. When the battery voltage is greater than the "full cutoff voltage", the switching device T1 is electrically conductive and composed at the same time. A1 is an overvoltage detection control circuit. The non-inverting input terminal of A1 is provided with a reference voltage corresponding to "overvoltage cutoff" by W1, and the inverting input terminal is connected to the side battery. When the battery voltage is greater than "overvoltage cutoff voltage", A1 output terminal G1 is low level, the switching device T1 is turned off, the charging circuit is cut off, and the overvoltage protection function is applied. When the battery voltage drops to less than the “overvoltage recovery voltage” after the overvoltage protection, the inverting input of A1 When the potential is less than the non-inverting input potential, the output terminal G1 transitions from a low level to a high level, and the switching device T1 is turned off by turning off, and the charging circuit is turned on again. The "overvoltage cutoff threshold" and "overvoltage recovery threshold" are adjusted by W1 and R1.
A2 is an undervoltage detection control circuit whose inverting terminal is connected to the undervoltage reference voltage provided by W2, and the non-inverting terminal is connected to the battery voltage (as opposed to the overvoltage detection control circuit). When the battery voltage is less than the "undervoltage threshold level" The output terminal G2 of A2 is low level, and the switching device T2 is turned off, and the output circuit of the controller is cut off to realize "undervoltage protection". After undervoltage protection, as the battery voltage increases, when the voltage is higher than the "undervoltage recovery threshold", the switching device T2 is turned back on, and the power supply to the load is resumed. The "undervoltage protection threshold" and "undervoltage recovery threshold" are adjusted by W2 and R2.
Solar PV controller product features
1. The photovoltaic controller adopts high-frequency switch isolation structure, which has high conversion efficiency, large adjustment range, small volume and light weight.
2. The photovoltaic controller adopts iron-based nanocrystalline magnetic material with high magnetic permeability, low loss and good energy saving effect.
3. The power supply transient response characteristics are good and the ripple is small.
4. The main components of the PV controller are imported and screened and aged, and strict production processes and testing methods ensure high reliability of the products.
5. Optimized circuit design enables the product to have rectification and monitoring charging functions at the same time, without additional monitoring equipment.
6, with overvoltage, overcurrent, short circuit, anti-reverse connection, temperature compensation.
7, panel voltage, current digital display function. Available in either in-screen or portable form factor.
8, according to customer requirements to optimize circuit design, provide solutions, develop prototypes, and strive to create better products for customers.
Circuit parameters of solar photovoltaic controller
1. Maximum charging current (A): ≤ 5
2. Maximum discharge current (A): ≤ 5
3. Battery rated working voltage (V): 12
4. Solar battery rated output voltage (V): 18
5. Solar cell maximum open circuit voltage (V): 25
6. Overcharge voltage (V): 14.8
7. Overdischarge voltage (V): 10.8
8. Restore the supply voltage (V): 12.3