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The solar PV system is constituted by the solar cell, storage battery pack, charge controller, inverter, AC power distribution cabinet, lightning protection system, combiner box, DC power distribution cabinet, environmental monitoring system, monitoring system and other devices. The following is the overview of the main components of a solar PV system.

Solar water pump systems are an efficient solution for providing water in remote areas where electricity is scarce or the power supply is unstable. With advancements in solar technology, these systems have become the preferred method for ensuring a reliable water source in sunny regions worldwide. Inverter.com will delve into the working principles, technical advantages, and the top ten reasons for installing a solar water pump system.

The light storage system includes solar energy components, controllers, solar inverters, batteries, loads and other equipment. At present, there are many technical routes, but the energy needs to be gathered on a certain point. At present, there are mainly two kinds of topological structures: DC coupling and AC coupling.

Leakage current of the photovoltaic system, which is also known as the square matrix residual current, is essentially a kind of common mode current. The cause is that there is parasitic capacitance between the photovoltaic system and the earth. When the parasitic capacitance-photovoltaic system-grid forms a loop, the common mode voltage will produce the common mode current on the parasitic capacitance. When the photovoltaic system is equipped with a industrial frequency transformer, because of the relatively high parasitic capacitance between the transformer windings in the loop, the common mode current generated by the common mode voltage in the loop can be suppressed to a certain extent. However, in a photovoltaic system with no transformer, the loop impedance is relatively low, and the common mode voltage will form a large common mode current, ie, leakage current, on the parasitic capacitance between the photovoltaic system and the earth.

IGBT is a kind of power device, which assumes the function of power conversion and energy transmission in the power inverter. It is the heart of the inverter. At the same time, IGBT is also one of the most unreliable components in the power inverter. It is very sensitive to the temperature, voltage and current of the device. In case of even a slight stand exceeding, it becomes incompetent and cannot be repaired. IGBT damage means the inverter must be replaced or overhauled. Therefore, IGBT is the key protection object of the power inverter.

Most of the PV inverters on the present market are generally in the IP65 protection level, with a certain degree of wind, dust and water resistance. However, in the summer, the ambient temperature is high, and various components in the inverter are prone to high temperatures during operation, resulting in a decrease in power generation efficiency and even affecting the service life of the components. Therefore, the inverter in some photovoltaic systems is installed with a sunshade to reduce the temperature of the equipment. In addition, the installation environment of the inverter should be well shaded and ventilated to ensure the convection of the air and also increase the power generation capacity of the power station

The energy flow path of the solar PV system usually contains a solar panel, a combiner box, a DC power distribution cabinet, a grid-tie inverter, an AC power distribution cabinet, and the connection cables. Based on the energy flow of the PV system, it is necessary to fully consider some important factors affecting the conversion efficiency in the design of the solar power system.

The installation scheme of common ground distributed projects is to install near a string of components at the closest. It adopts the fixed-rack installation or hoop-type installation to directly fix the equipment on the stand column. If this kind of scheme is used, it is required to pay attention to the strength of the rack and column, as well as the height of the solar PV inverter over ground, avoiding being submerged in stormy days because of being placed at a too low height.

The PV module capacity and solar inverter capacity ratio are commonly referred to as capacity ratio. Reasonable capacity ratio design needs to be considered comprehensively in the light of the specific project. The main influencing factors include irradiance, system loss, inverter efficiency, inverter life, inverter voltage range, assembly installation angle and so on. Because the inverter accounts for only about 5% of the system cost, the number or power of the inverter is reduced by the overmatching of the components in the distributed photovoltaic power station system, and the investment income is very small, which also bring other problems, the specific analysis is as follows.

Is an inverter necessary for the RV or how to choose the right one. As a matter of fact, it depends on our electricity demand. The 12V battery of the RV can only enable electrical appliances with low power to work normally, such as 12V refrigerator and LED light, ventilation fan or small TV. If you want to use a high-powered electric appliance such as a rice cooker, a microwave oven, an electric kettle, or an induction cooker, you need a power inverter.

Input overvoltage protection: When the DC-side input voltage is higher than the maximum allowable DC array access voltage of the grid tie inverter, the inverter is not allowed to start or stop within 0.1s (in operation) and a warning signal is released at the same time. After the DC-side voltage is restored to the allowable working range of the inverter, the inverter should be started and operated normally.

In outdoor electric projects, there are usually difficulties of power acquisition or high powering construction cost. Adopting the solar power supply is a common solution, which is widely used in outdoor wireless network coverage and outdoor wireless monitoring.

The micro-inverter technology directly combines the inverter with a single photovoltaic module to equip every photovoltaic module with an inverter module which is capable of DC-AC conversion and the MPP tracking. The inverter module can directly convert the power generated by the photovoltaic module into the AC for the AC load use or transmit it to the grid.

Charging controller, check the voltage setting of the rectifier and check the voltmeter to have normal indication. If the battery temperature is below 55°F (about 12.778°C), charging to a higher voltage (at least 14.8 volts for a 12 volt system) should be allowed. If your charge controller has the temperature compensation function, it will automatically adjust. If there is an external temperature sensor, please make sure that it has been attached to the battery. If there is no automatic adjustment function, it is required to manually increase the voltage and adjust back in the spring (adjust to 14.3 volts). If the charge controller is not adjustable, try to keep the battery in a warmer environment.

As one of the multiple development and utilization approaches of solar energy, solar photovoltaic power generation has the characteristics of pollution-free, renewable, flexible and storable and so on. The photovoltaic power generation system has been put into practical use in the fields of road lighting and residential construction. The water treatment industry is also suitable for the application of the photovoltaic power generation system because of its unique industry characteristics. The solar photovoltaic system is composed of a solar battery pack, a solar charge controller, and a battery.

The application of the photovoltaic power generation system has the following advantages in the wastewater treatment industry:

No sheltering of tall buildings around

Most of the water treatment plants are located in areas with relatively concentrated industrial enterprises and remote positions. The surrounding buildings are mostly low-rise buildings such as industrial plants, and there is less shielding for the photovoltaic power generation system in water treatment plants. At the same time, since the construction condition of the water treatment plant itself, the structure and the building unit itself are low in height and sparse in layout, and are not easy to cause occlusion, thus having better illumination conditions.

Rather big installable roof area

Due to the need of the technological procedure, most water treatment plants have rather big architectures, such as biological reaction tanks, secondary sedimentation tanks, blower rooms and so on, which usually have large installation spaces for photovoltaic systems above. In addition, the photovoltaic power generation system of the water treatment plant mostly belongs to the roof-type distributed photovoltaic system, thus involving no newly increased land, changing no land application, affecting no cultural relic protection requirement, increasing no building area and changing no building structure.

Improve the technological treatment effect

The reasonable layout and design of the photovoltaic power generation system of the water treatment plant can reduce the evaporation amount of the pool water, increase the water treatment capacity, reduce the impact of sewage evaporation on the environment. At the same time, it can still reduce the wind speed above the pool, improve the local small environment, increase the temperature of the pool water, enhance the growth activity of the microorganisms, improve the sewage treatment effect, and finally achieve the purpose of improving the water treatment capacity and the comprehensive economic benefits of the project.

High and stable power generation of the water treatment plant

The loads of water treatment plant include high-power loads such as blowers and submersible pumps, as well as low-power loads such as gates, grilles, and submersible flowers, which usually have higher computational powers. Moreover, due to the relatively balanced water volume, the operation of each technological equipment is relatively stable, and the load characteristics are stable, thus being convenient for the design of the solar photovoltaic power generation system.

Since the water treatment plant has great power consumption and small changes, the reasonable design of the photovoltaic system can fully utilize the photovoltaic power, avoid power waste of the solar inverter, and reduce the light rejection rate.

Good financing conditions

Water treatment plants usually have long operating cycles, guaranteed operations, stable benefits, high self-sufficiency ratio, and high return on investment, thus avoiding the problem of financing difficulties.

Low maintenance cost

After the establishment of the solar photovoltaic system, its operating costs, in addition to equipment damage caused by force majeure, are mainly the cleaning water expense and other maintenance costs. The cleanliness of the effluent or recycled water of the sewage treatment plant can meet the cleaning needs of the PV modules. At the same time, the water source after cleaning can be directly collected into the sewage treatment process, thus saving water and reducing maintenance costs.

The off-grid solar power system design is different from the grid-tie solar power system. The former needs to take into consideration many factors including the load, daily electricity quantity local climate conditions, and so on, to choose different design plans according to clients’ practical demands. Therefore, the off-grid solar photovoltaic system is comparatively complex. To ensure the reliability of the off-grid PV system, a thorough survey of customer demands is very necessary. The design of an off-grid solar power system is mainly composed of the inverter selection, solar panel capacity, and battery capacity.

Now we take a design of an off-grid solar power system for a small-scale fish farmer near a lake as a case study. Due to the long-distance power grid construction, not only is the cost high, but the power loss and voltage loss of the wires are also huge. Meanwhile, the stability of power use cannot be ensured because typhoons and accidental power failures happen on a frequent basis, which can affect the power used for production and life. Therefore, the off-grid solar power system is adopted. The sunlight radiation intensity in the daytime is high, and the power generated by the solar power system is directly provided to the solar inverter output to support the operation of electric devices. At the same time, the batteries are charged, and provide the power for the devices via the inverter at night.

In fact, there is a close connection between the photovoltaic power generation capacity and the grid voltage. The power generation capacity gap between regions with extremely unstable voltage and regions with stable voltage is around 10% to 20%. This paper mainly discusses the influence of the grid voltage on the system. The grid voltage can be divided into three conditions, namely low voltage, high voltage and dramatic voltage fluctuation. These three conditions will all influence the system’s power generation capacity.

To a solar energy grid-tie system, the time and climate will cause changes of solar radiation, thus resulting in constant changes of the power point voltage. In order to improve the generating capacity, and ensure that the solar panels can output the highest power, either when the sunshine is weak or when the sunshine is strong, the solar inverter usually introduces the boost circuit to expand the voltage of its working point.

The Maximum Power Point Tracking (MPPT) system is an electric system which can ensure the photovoltaic panel to output more electricity by adjusting the electric module’s working status. It can effectively store the DC emitted by the solar cell panel in the accumulator to effectively resolve the problem with the conventional grid that the domestic and industrial power use in remote areas and tourist destinations is not satisfied, while avoiding causing environmental pollution.