博文

目前显示的是 三月, 2016的博文

Introduces a new type of high efficient and stable solar energy inverter

图片
The output end of the early  solar energy inverter  system generally installed isolation transformer, to realize voltage adjustment and electrical isolation, to ensure safe and reliable operation of the system. However, isolation transformer of large volume, high cost, high loss, affect the system efficiency. If the use of high-frequency transformer to achieve the electrical isolation of PV and grid, which can reduce the system volume, quality and cost, but will not significantly improve the efficiency of the system. Therefore, non isolated grid connected photovoltaic inverter system has become a hot research topic. It has the advantages of high efficiency, small size, light weight, low cost and so on. But the elimination of transformers build electrical connection between PV and grid, leakage current could be increased substantially, conducting radiated interference, increase the net current harmonics and loss, even to endanger the equipment and personnel. Therefore, the common mode

The performance parameters of solar powered inverter

图片
There are many performance parameters and technical conditions of the  solar powered inverter , here only a brief description of them. 1.Environmental conditions: altitude is not more than 1000m, air temperature of 0 ~ +40 ℃. 2.DC input voltage fluctuation range: ±15% of battery rated voltage. 3.Rated output voltage. In the specified input power supply conditions, when output the rated current, the rated voltage should be output by the  solar energy inverter . Voltage fluctuation range: single phase 220V ± 5%, three-phase 380 ± 5%. 4.Rated output current. In the specified output frequency and load power factor, the rated current value should be output by the inverter. 5.Rated output frequency. Under specified conditions, the rated output frequency of fixed frequency inverter is 50Hz, the frequency range of 50Hz ± 2%. 6.The maximum harmonic content of the solar inverter. Under the resistive load, the maximum harmonic content of output voltage should be less than or equal to 10%. 7.Overl

The application of home solar power system

图片
China has abundant solar energy resources, if wel make full use of them, can not only save a lot of conventional energy, but also can fully use of solar heating in some areas. Solar photovoltaic power generation technology can be used for any electric field, from the spacecraft to the home power supply. With the development of photovoltaic technology, gradually expand the application of photovoltaic power generation, solar photovoltaic products is mainly used for three aspects so far: one is for electric power supply; solar daily electronic products, such as various solar charger, solar street lighting, and so on; grid connected power generation, which has large area popularization and implementation in developed countries. Home solar power system  is becoming more and more mature and widely used. Germany’s million solar roofs plan makes many families use of solar photovoltaic power generation to resolve the problem of their own power supply and the family also accomplishing priva

Disadvantages of modular uninterruptible power supply

图片
The difficulties in the development of the  modular uninterruptible power supply  are mainly in the increase of the power density, the increase in the number of parallel, and the reduction of the price. Rack mounted modular UPS developed from the traditional vertical (tower type) structure, has wide cooling channel and a vast volume and high power cooling fan compared with the traditional vertical (tower type) structure, modular UPS is smaller and lighter to facilitate the replacement of the monomer. Due to the limit of the size, in the case of UPS module power increased, the heat dissipation has become a big problem. In order to achieve the purpose of safe work,  modular UPS syetem  not only uses the original passive heat dissipation, active cooling, axial flow and air duct diversion type cooling technology, but also uses the heat pipe cooling. In order to ensure the maximum availability and scalability of the power supply, the modules should be used in parallel without limitation. Wh

Installation considerations of BC Series Battery Cabinet

图片
With the size of  power cabinet , and then check the appearance of equipment, ensure matching wtih the selected support. A rugged cabinet can bearing weighing up to 450 pounds, so it is necessary to check the tools that handling equipment, such as lifting or trolley. The  power distribution cabinet   on wheels, so you only need to put the equipment installed in the cabinet, pushed to the right place. Measure the size of the room and the height of the ceiling, doors and lift to make sure that the cabinet can be passed. In addition, consider to the many types of equipment in the cabinet, to ensure that the cabinet is near the power, network cable spigot and communication socket. Check the angle of cabinet door open and closed. Standard cabinet door open on the right and the hinge on the left, of course, does not rule out the opposite situation. All the doors and side panels should be easy to open, easy to maintain. When you want to install equipment cabinet into an existing group, you ca

Protection function of rack mount UPS

图片
1.Battery low voltage protection: the battery will stop the power supply after discharge to a certain extent, to prevent the battery from permanent damage cause to excessive discharge. 2.Input overvoltage protection: precise control technology, cut off the AC input and continue uninterrupted for electrical equipment provided in compliance with the requirements of the power when the input voltage is too high or too low, prevent city electrical voltage is too low or too high to damage the device. 3.Output high voltage protection: when output voltage is too high due to sudden or unexpected events, the  rackmountable UPS  will alarm, city electric switch to bypass, cut off output if there is no electricity, so as to protect the UPS and electrical equipment. 4.Overload protection: the series of HP9115CRT  rack mount UPS power supply  collect load conditions in real-time, take different ways of protection for different degrees of overload, UPS can work in less than 120% overload for a long t

Two kinds of representative structures of modular type UPS

图片
One kind is power  modular type UPS . Power modular Rackmount UPS is composed of a rackmount and power module, the power module including traditional UPS rectifier, filter, charging, inverter and so on. But the static bypass and the part of the system monitor and display the same rackmount. Each module is independently controlled in parallel operation, and the display control module on the upper part of the cabinet is only used as a platform to switch the UPS host and network monitoring by the user. The rackmount  modular uninterruptible power supply  is composed of rackmount and single module composition, each module is equipped with the UPS and the control circuit, including rectifier, inverter, static bypass switch and auxiliary control circuit, CPU main control panel. Each UPS module has an independent management system. Relative to electronic technology and components development, two kinds of structure have their own advantages, also have very good representative products, provid

Step wave solar powered inverter introduction

图片
The waveform of the output of the  solar powered inverter  is step wave, and there are many kinds of different lines to output step wave, and the number of the output waveform is very different. The advantage of the step wave  solar energy inverter  is that the output waveform is significantly improved than the square wave, the higher harmonic content is reduced, and the modified sine wave can be realized when the step is more than 17. When there is no transformer output, the efficiency of the whole machine is very high. The disadvantage is that there are more power switches used in the step wave superposition circuit, and some of them are also required to have multiple sets of DC power input. These bring trouble to the grouping of the solar cell array and the balance charging of the wiring and the accumulator. In addition, the step wave voltage still have some high-frequency interference on the radio and some communications equipment .

Note the maintenance of solar panels inverter systems

图片
(1) when the continuous rain and the battery power is large, whether or not the battery pack to the discharge termination voltage, should be timely recharge the battery with the mobile power generation device. To prevent the battery capacity is not full, then to the rainy day, resulting in power supply interruption, and due to battery is not charged in time after discharge leading to reduce the battery life. (2) due to battery operation mode is not completely float operation mode, the battery service life is shorter than that of the conventional power supply system. Should grasp the battery capacity, especially after a few years of use, should test the capacity of the battery group before the rainy season comes, if the capacity can not meet the requirements, should take measures timely. (3) the cable connect the solar cell array to the solar power supply combined power supply is partly outdoors, should regularly check whether the cable is aging and the connection is intact. (4)

Introduction of square wave inverter

The AC voltage waveform of  square wave inverter  is square wave. The circuits used in such inverters are not exactly the same, but the common characteristic of them is that the circuits is relatively simple, and use a small number of power switches. The power is generally designed between 100w to 1kw. Square wave inverter has the advantage of simple, cheap, easy to maintenance. The disadvantage is that due to the square wave voltage contains a large number of high harmonics, with iron core inductance or transformer load with electrical equipment will produce additional loss, and can interfere some communication equipment. In addition, this type of inverter has some other disadvantages such as the voltage regulation range is not wide enough, the protection function is not perfect, the noise is relatively large and so on.

The functions of solar powered inverter

图片
Solar powered inverter  not only has the function of direct AC conversion, but also has the fuctions of maximize solar cell and system maintenance. Here we introduce the functions of active operation and shutdown , and maximum power point tracking briefly. 1.Active operation and shutdown After sunrise in the morning, the intensity of the solar radiation is gradually strengthened, and the output of the solar cell increases. When the output power of the inverter is reached, the solar powered inverter is active. After entering the operation, the inverter will always look after the output of the solar cell module, as long as the output power of the solar cell component is greater than the output power of the inverter need, the inverter will continue to run; until sunset, the inverter shut down. The solar powered inverter can run even if the rainy day. When the output of the solar cell module becomes smaller, the output of the inverter is close to 0, the inverter will enter the standby

Two problems to be solved for the solar module inverter

图片
The  solar module inverter  links the each PV module to a inverter, while each component has a separate maximum power peak tracking, so that the PV module is better matched with the inverter. Usually used for 50W to the 400W photovoltaic power generation station, the total efficiency is lower than the string inverter. Since the communication is in parallel, this increases the complexity of the connection of the AC side, and difficult to maintain. Another problem need to be solved is that how to connected with power grid more effectively, the simple way is to connect directly through the common AC socket. Thus can reduce the cost and simplify the equipment installation, but usually the grid safety standards of different cities may not be allowed to do so, the power company may against power devices directly connect to ordinary home users’ sockets. Another security related factor is whether or not to use the isolation transformer (high frequency or low frequency), or to allow the use of

The manufacturing process of outdoor electric enclosure

图片
The appearance of coating Surface coating should be continuously and evenly. Texture should be same to the corresponding standard model consistent, and no nodulation, shrinkage, foaming, pinhole, cracking, peeling, powder, granule, flow hanging, threadbare, mixed with dirt and other defects. For non spraying processing  outdoor battery cabinet , surface gloss and texture should be uniform and beautiful. The adhesion of coating The coating surface of the cabinet through adhesion test, to meet the requirements of GB/T 9286-1998 level 1. The impact resistance of coating The  outdoor battery enclosure  surface without radial crack and notch and other defects coating after impact test. Anti-aging coating The  outdoor electric enclosure  surface anti-aging coating. Solvent resistant coating The the coating of cabinet surface should not appear obvious loss of light, and wiped signs fade after solvent resistance test.

The development of outdoor network enclosure

图片
The early period  outdoor network enclosures  are made mostly by casting or angle connected through the screw and rivet, or the welded into the frame of cabinet then install the door made of a thin steel plate. This kind of  outdoor power enclosure  has been eliminated as it is big, bulky and shabby appearance. With the use of transistors and integrated circuits, various components become super small, the structure of cabinet develop toward the direction of miniaturization and modularization. The outdoor network enclosure has developed from the past whole panel structure into a certain size series of plug box and plug in structure. The assembly arrangement of plug box and plug in is divided into horizontal and vertical arrangement. The materials of network cabinets commonly used thin steel plate,various shape of the steel or aluminum, and various engineering plastics etc.. The outdoor power enclosure frame network not only connected by welding and screws, but also bonding process.