On June 5, the SNEC 2019 PV POWER EXPO came to a successful conclusion.”Global green energy and photovoltaic financial summit” will bring together senior experts and stakeholders of photovoltaic industry to discuss and deal with challenges and opportunities of industry development.The global photovoltaic industry, especially in China, is developing rapidly and the market is growing significantly.The integration of household photovoltaic, distributed photovoltaic, energy storage, big data + artificial intelligence, smart energy micro grid, Internet of things and other industries is getting closer.The rapid growth of the renewable energy industry has also created a huge demand for capital.Innovation green finance, adapt to the new trend of development to become a new topic of industry development.In order to adapt to the new trend of finance, new energy and Internet digitization, the conference will explore how to integrate the three major elements of finance, new energy and energy Internet, how to tap the potential of each to promote mutual promotion, form a new pattern, and promote the restructuring of energy system in the global society.
After careful preparation, SOROTEC rely on the exquisite technical level, the world’s leading research and development technology, scientific laboratory, high performance of all kinds of power equipment once again become one of the highlights in the industry.The ingenious design and accurate research data have attracted many Chinese and foreign merchants to stop to watch and consult.Many buyers have brought technical problems in the field of power supply. After the technical guidance and optimization of internal components by our high-quality engineers, many customers are satisfied and purchase intention is reached on the spot.
Switching power supply is to use electronic switching devices (such as transistors, field effect transistors, thyristors, etc.) to make electronic switching devices “turn on” and “turn off” continuously through control circuits, so that electronic switching devices can modulate the input voltage, thus realizing DC/AC, DC/DC voltage conversion, as well as adjustable and automatic voltage stabilization of the output voltage.
There are generally three modes of switching power supply: fixed frequency and pulse width mode, fixed frequency and variable pulse width mode, and variable frequency and pulse width mode. The former mode is mostly used in DC/AC inverters or DC/DC voltage conversion, while the latter two modes are mostly used in switching regulated power supply. In addition, the output voltage of switching power supply also has three working modes: direct output voltage mode, average output voltage mode and amplitude output voltage mode. Similarly, the former is mostly used in DC/AC inverters, or DC/DC voltage conversion; the latter two are mostly used in switching regulated power supply.
According to the way switching devices are connected in the circuit, switching power supply can be generally divided into three categories: series switching power supply, parallel switching power supply and transformer switching power supply. Among them, transformer switching power supply (hereinafter referred to as transformer switching power supply) can be further divided into push-pull, half-bridge, full-bridge and other types; According to the phase of transformer excitation and output voltage, it can be divided into forward, flyback, single and double excitation. If it is divided into uses, it can also be divided into more categories.
1.Constructed with standard 19 inch screen, which has the advantage of wide use. 2.The data center area and the installation cost can be saved due to its small size and the embedded installation. 3.Wide input voltage range (85-290Vac), the power grid is adaptable. 4.Perfect lightning protection. 5.Rectifiers are hot-pluggable. Easy and quick on line maintenance. 6.The rectifier uses DSP (Digital Signaling Processor) ology, makes the power density ran up to 14W/In3. 7.Battery management, prolongs the life of the battery well. 8.Have passed CE, UL, TLC, and other related certifications. 9.Excellent energy conservation and environmental protection.
Nowadays, many people like to talk about “power quality”. There are many products of power quality, such as SVG, APF and three-phase unbalanced regulator, which have become “hot-selling products”. But what are the benefits of improving power quality for people?
Improving power quality is of great significance to the safe and economic operation of power grid, ensuring the quality of industrial products and the normal conduct of scientific experiments, and reducing energy consumption. Power quality is directly related to the overall benefits of the national economy. Good power quality is undoubtedly beneficial to the operation of electrical equipment, but the adverse impact of poor power quality on the operation of power system has not attracted enough attention. From the point of view of harm degree, the harm of some power quality problems is destructive. For example, the overvoltage caused by harmonic resonance in lightning impulse, capacitor and cable switching often causes insulation and mechanical damage of electrical equipment, thus affecting the normal operation of power system. The misoperation of relay protection device caused by harmonic and negative sequence interference will cause huge economic losses in large-scale blackout of power grid. Short-term power supply interruption or voltage drop may lead to production chaos or a large number of industrial smelting products scrapped or even endanger personal safety. On the other hand, some power quality problems mainly affect the performance indicators of electrical equipment. For example, abnormal voltage and frequency deviation will cause the change of speed and power of asynchronous motor load, which will reduce the efficiency of transmission machinery and affect the quality of textiles, papermaking and other products. Harmonic currents circulate in transmission and distribution equipment such as rotating motors, transmission lines and transformers, which overheat these equipment due to additional losses, thus reducing the life or capacity of these equipment. However, it can not be explained that the former power quality problem is more important than the latter. The actual situation is that the latter power quality problem, due to the wide range of electrical equipment involved, has the same impact as the former power quality problem.
There have been a lot of achievements on the study of the harm of deterioration of power quality indicators to electrical equipment. However, different indicators of power quality have different effects on different equipment. Especially when there are multiple indicators of power quality, the impact of different combinations on equipment is a very complex problem. At present, there is no accurate quantitative formula, only some rough formulas and conclusions. The results can be used for engineering estimation.
Therefore, in general, the closer the power quality index is to the rated value, while ensuring continuous and reliable power supply is the symbol of high quality of power. However, from production to consumption of electric energy is an integral whole. The generation, supply and use of electric power system are always in a dynamic balance, and any link of it will have an impact on the quality of electric power. The control of power index needs considerable investment (including the improvement of power grid structure, the balance of active power and reactive power, the use of various frequency modulation, voltage regulation, filtering and reactive power compensation devices, as well as the technical management of dispatching and operation), and the control technology of various index is constantly developing and improving. In fact, the deviation between the power quality index and the rated value is inevitable. The task of formulating power quality standards is to determine the appropriate allowable deviation of power quality indicators from the current (or recent) technical level.
The criteria for judging whether the criteria are reasonable or not should be: 1.Basically, it can ensure the security, continuous power supply and economic operation of the power system. 2.On the whole, it can ensure the normal use of electricity for users’electrical equipment. 3.On the basis of the current technological level, the power sector (including interfering users) should be able to meet the standards after making certain efforts.
Meeting users’ requirements: – PF=0.99 and THDi < 5% – Compensation for 2- to 50-order harmonics – Capacitive and inductive reactive power compensation – Three-phase unbalance co
In the fault area of the outdoor cabinet, the cabinet is usually made of cold rolled steel or alloy, which is used to store computer and related control equipment. It can provide protection for storage equipment, shield electromagnetic interference, arrange equipment in an orderly and orderly manner, and facilitate the maintenance of equipment in the future. Cabinet is generally divided into server cabinet, network cabinet, console cabinet and so on. As the user of cabinet, you must know the fault area of cabinet.
Fault area 1: below the cabinet (outside the cabinet)
The area below the rack and above the floor is difficult to manage because leveling bolts or casters vary in size and manufacturer and height. There will be a lot of uncontrolled air in this area. If the area can be properly sealed, it can produce very high benefits. Usually, there is no solid baffle under the cabinet due to the need to connect wires or nets. This will also lead to air leakage in the area, because the heat under the cabinet cannot be released, and the cold air from the perforated floor will also bypass the area.
Fault area 2 and the left and right sides of 3:19 inch cabinet front vertical rail (cabinet interior)
Because customers require that the front-end guide rail can be adjusted and they want to be able to pass through cabinet wiring, most 19-inch cabinet front-end guide rail has leakage points on both sides. The area between the vertical guide rail and the rack or side panel is usually open, allowing hot air to penetrate or cold air to pass through. This will seriously damage the stability of blind strategy. Today’s widened racks (e.g. 800mm) have a 3-inch redundant width on both sides of the 19-inch cabinet rail to cool switches or facilitate the installation of a large number of wires. The cable passes through an unsealed opening and passes through the side or top. These openings should be covered with appropriate materials to seal the voids around the cable and reduce air leakage.
Fault area 4 and 5: top and bottom of bracket mounting space (cabinet interior)
Air leaks may occur in areas above the top U and below the bottom U. Usually, these areas have some space, which varies according to the rack manufacturer. However, this area is the same as that without blind plate. This area is susceptible to hot air recirculation, and cold air from air conditioning is more likely to bypass this area.
SOROTEC outdoor battery cabinets was developed for easing customers, pressure in site acquisition, meeting customers,requirements for energy saving and flexible expansion. As an innovative installation solution for site equipment,it not only has a large housing capability like traditional shelter, but also adopts independent compartment temperature control method as outdoor electric enclosures.Because outdoor battery cabinets has few limitations on application scenarios and can satisfy customers,different requirements, it is gaining more and more popularity in modern site.
With the progress of power electronics technology and control technology, domestic active harmonic filter has replaced imported products in various major projects. In 2012 alone, the sales of domestic APF products have exceeded the imported brands by five times. Active power filter will eventually replace the traditional passive filter because of its huge technological advantages, powerful functions and declining price.
During the development of APF, modular APF equipment has gradually replaced traditional cabinet APF with its advantages of small size, convenient installation, high integration, stable operation and convenient expansion. In the next five years, the combination of modular APF and static var generator (SVG) will become the most powerful solution in power quality industry, and will be widely recognized by the market.
Meeting users’ requirements: – PF=0.99 and THDi < 5% – Compensation for 2- to 50-order harmonics – Capacitive and inductive reactive power compensation – Three-phase unbalance co
