博文

Factors affecting the efficiency of the inverter

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The only way to improve the efficiency of the inverters is to reduce the losses. The main losses of the solar inverters come from IGBT, MOSFET and other power switches, as well as magnetic devices such as transformers and inductors. Loss is related to the current and voltage of components and the process adopted by the selected materials. The losses of IGBT are mainly conduction loss and switching loss. The conduction loss is related to internal resistance and current passing through the device, switching loss is related to switching frequency of the device and DC voltage of the device. The main loss of inductance is copper loss and iron loss. Copper loss refers to the loss caused by the resistance of inductance coil. When the current is heated by the resistance of inductance coil, part of the electric energy is transformed into heat energy, which is called copper loss because the coil is usually wound by insulated copper wire. Copper loss can be calculated by measuring short-circuit…

How to Improve the efficiency of Inverter

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There are currently three technical routes. First, space vector pulse width modulation (SVPWM) is used to reduce the loss. Secondly, silicon carbide materials are used to reduce the internal resistance of power devices. Third, three-level, five-level multi-level electrical topology and soft switching technology are adopted to reduce the voltage at both ends of power devices and the switching frequency of power devices.
1.Space Vector Pulse Width Modulation (SVPWM) SVPWM is a fully digital control method, which has the advantages of high utilization rate of DC voltage and easy control. It is widely used in inverters. With high utilization of DC voltage, lower DC bus voltage can be used under the same output voltage, which reduces the voltage stress of power switching devices, reduces the switching losses on devices, and improves the conversion efficiency of inverters to a certain extent. In space vector synthesis, there are many combinations of vector sequences. Through different comb…

Comparing 48V and 12V power supply from the voltage allowable range

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We know that the input voltage range of 12V power supply server motherboard is usually 5% positive and negative difference. If we adopt the structure of 12V bus + 12V battery BBU, it is difficult to achieve this voltage allowable range. Especially at high currents that may be as high as 23,000 amperes, the voltage drop at impedance of 1 milliohm is as high as 2 or 3 volts, and the voltage drop of copper exhaust is much higher than the voltage range of 5% or about 0.6 V. If the voltage drop is controlled by current sharing among multiple power outlets and buses, in addition to the cost and space mentioned above, additional DC/DC voltage stabilization circuit is needed to ensure the voltage reduction caused by BBU discharge. The total cost of this DC/DC voltage regulator circuit will be very high, which will also lead to the overall uneconomical system. In 48V bus structure, the main board usually has a wide range of input voltage of 36V-58V, bus voltage drop is no longer a problem, an…

What is solar controller

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The solar energy control system consists of solar panels, batteries, controllers and loads. Solar controller is a device used to control photovoltaic panels to charge batteries and provide load controlled voltage for voltage sensitive devices. It regulates and controls the charging and discharging conditions of the battery, and controls the output of the solar cell module and the battery to the load according to the power demand of the load. It is the core control part of the whole solar power supply system. It is specially designed for the power supply system of telecom communication or monitoring equipment in remote areas. The charge control and load control voltage of the controller are fully adjustable, and the battery voltage, load voltage, solar array voltage, charge current and load current can be displayed. Almost all solar power systems powered by batteries need a solar charge and discharge controller. The function of the solar charge and discharge controller is to regulate t…

Surface oxidation of integrated cabinets should be handled in a timely treatment

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The surface oxidation of the integrated outdoor cabinet needs to be treated in time. When making the sheet metal cabinet, the thickness of the metal must be higher than that of the processed products. However, because metal materials are produced in large quantities by manufacturers, it is inevitable that they will encounter oxidized materials. For such materials, how should we deal with it? Oxidation is a common problem, especially for industrial equipment. Paint spraying or electroplating are usually used for antioxidant treatment on equipment, but oxidation can not be avoided in an all-round way. Because the sheet metal cabinet is made of different materials. Therefore, we need to pay attention to the selection of materials, especially whether metal materials are overoxidized, if this is the case, we can not choose this plate processing. Firstly, the limited stainless steel is heated by shearing, edge binding, welding or artificial roasting, which results in black oxide skin. In t…

Advantages and disadvantages of using lithium battery in data center

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VRLA batteries are commonly used in three-phase sources of UPS systems. Because of its weight and size, data centers need to have an enhanced load bearing structure. The performance characteristics of VRLA batteries will also be affected by temperature, thus increasing the load of the air conditioning system. VRLA batteries are not particularly durable and need to be replaced at regular intervals, which also results in an increase in operating costs. Because VRLA batteries are not economically viable alternatives, design engineers must tolerate their shortcomings. However, the situation of lithium batteries has changed in recent years. The first uninterrupted power supply system powered by lithium batteries was launched in 2016. Lithium batteries are now used in all major factories, and this direction has been recognized as the most promising choice. As of 2025, the lithium battery solution will account for 40% of the UPS market in the data center. When the capacity of lithium-cobalt…

Is inverter suitable for capacity reduction?

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At present, there are many types of inverters on the market. In order to simplify the management and explore the advantages of centralized purchasing, many EPC manufacturers often use limited types of inverters to design as many cases as possible, which will inevitably involve the use of inverter capacity reduction. Small scale capacity reduction is not a big problem. However, the use of large-scale capacity reduction, not only will cause a waste of inverter costs, but also can not get the desired power generation.
1.Waste of resources
For a simple example, the original 10kW inverter used to carry 6kW photovoltaic components, equivalent to the inverter used only 60% of the workload, time will inevitably lead to waste of resources, not conducive to the LCOE optimization. Of course, the small case is good, if it is a MW large case, waste can not be ignored.
2.Shorten the string length and reduce overall power generation. (a)Not conducive to string optimization design
For some power level …