We have been specializing in designing and manufacturing a great variety of new and high-tech products, which include Emergency Power Supply (EPS),PV Grid-connected inverter,Wind Turbine on grid inverter,PV charge controller and DC-DC converter etc. It is our mission to provide for our customers the most innovative, high quality, effective-cost products and the best services since SPS founded. Based on the demands of domestic and international market, this mission can be accomplished by utilizing art-of-the-state professional design,advanced manufacture technology, on a large-scale production and well organized management. SPS has lots of expertise,which are high-tech talent and possess of Ph.D and Master degree and focus their mind on power and electronic products research.SPS also has ten thousands Power Supplies manufacture capability per year.

During the installation and construction of PV power station or household system, consideration should first be given to the following factors:   1．PV power system shall be designed in such a way that its highly reliable performance and normal operation under severe conditions can be guaranteed. Meanwhile, the system is required to be easy for operation and maintenance, thus convenient for users’ operation and daily maintenance.   2．Considering the low-cost design, manufacturing and construction of the complete set of PV power system, standardized and modularized design of the equipment and enhancement of the versatility and interchangeability of spare parts, it is required that the system shall reserve expansion interface for the future increase of scale and capacity.   3．During concrete implementation, the solar module shall be installed with appropriate azimuth angle and inclination angel, so as to ensure that the solar module achieves most optimized performance. Selection of the installation place shall guarantee that the module can be irradiated by sunlight from 9:00 AM to 3:00 PM during days with minimum exposure time throughout the year in the local area.   4．Installation structure of the module shall be able to resist environmental stress of wind, snow, etc. and the mounting holes shall guarantee easy installation and protection from mechanical stress. It is recommended to use correct materials for installation structure so that corrosion of the module frame, installation structure and materials could be reduced to the minimum.

As required, PV power system is generally installed outdoors to endure the test of wind, rain, sun, etc. Continuous and stable power supply is required. As for natural and weather conditions, most consideration is given to continuous overcast and rainy days. Therefore energy balance design shall be made for the power system, and the operation mode with most severe requirement for PV power system shall be adopted for design. In this way, it can be ensured that the system can provide normal power supply to the loads at different times, in different seasons and under different climatic conditions.

When the photovoltaic module operating, it shall be installed in a direction so that sunlight irradiation can be received at the maximum. In consideration of the change of sunlight incidence direction in a day and the difference of solar altitude from the horizon line in winter and summer, it is recommended that generally the module shall be installed inclined towards the equator. That is to say, in the Northern Hemisphere the light-receiving surface of the module shall be directed towards the sough and in the Southern Hemisphere the light-receiving surface of the module shall be directed towards the north. Generally, for the angle between the module and the ground, reference shall be made to local latitude±(5°~10°)。

Stand-alone systems are independent from the utility grid,avoiding the possibility of losing power when the grid goes down.Electricity from stand-alone systems are used on site,such as an RV or cabin.Power that is generated can be stored in batteries and used at night or on sunless days. A generator may also be used for back-up.For PV applications,the size of a stand-alone system is usually up to 50kW.

The system diagram as follow

System includes:

1. PV Array: A number of PV panels connected in series and/or in parallel giving a DC output out of the incident irradiance. Orientation and tilt of these panels are important design parameters, as well as shading from surrounding obstructions.

2. PV controller:control battery bank charge and discharge reasonable and safety.

3. Inverter: A power converter that "inverts" the DC power from the panels into AC power.The characteristics of the output signal should match the voltage,frequency and power quality limits in the supply network.

4. Battery bank: can be a single battery or multiple batteries connected together to create essentially one large battery of the required voltage and amp-hour capacity.In some ways the battery configuration and capacity are the most important electrical power decision to make, and a wise choice can help guarantee a steady supply of electrical power as well as a system that is simple to operate and maintain.

5. Loads: Stands for the network connected appliances in the building that are fed from the inverter, or, alternatively, from the grid.

In photovoltaic solar energy systems, light is converted into electrical energy that is used immediately or stored. In a grid connected photovoltaic system, the generated direct current is transformed into an alternating current that can be used in the house immediately. In case of a¡¡remainder of energy, it can be delivered into the grid.

Grid connected system avoid the need for electricity storage in batteries by essentially using the utility as a battery system. When your solar or wind system produces more electricity than you need, the excess is sold back to the utility.When your system doesn"t produce enough electricity,you can draw power from the grid.All this is done automatically through a net metering or net billing program.In most cases,a special or second utility meter will be added to keep track of how much electricity has been sold to the utility.¡¡

Advantages of utility interconnection include having access to standard AC power all of the time,not just when your system produces electricity,and avoiding the cost of a battery back-up system.A disadvantage is the utility interconnection fee,which varies with each utility.The size of a utility connected project depends on how much of your electric consumption you want to displace and how much money you are able to invest.

Grid Connected PV system design has the following components:

1. PV Array or Generator: A number of PV panels connected in series and/or in parallel giving a DC output out of the incident irradiance. Orientation and tilt of these panels are important design parameters, as well as shading from surrounding obstructions.

2. Inverter: A power converter that ¡°inverts¡± the DC power from the panels into AC power. The characteristics of the output signal should match the voltage, frequency and power quality limits in the supply network.

3. Loads: Stands for the network connected appliances in the building that are fed from the inverter, or, alternatively, from the grid.

4. Meters: They account for the energy being drawn from or fed into then local supply network.

5. Local Supply Network: A single or three-phase network managed by a Public Electricity Supplier. The supply network acts both as a sink for energy surplus in the building or as a backup for low local generation periods.