Jul 25, 2020
At present, the electrical equipment of some photovoltaic power stations in China continues to fail after several years of operation. The innate deficiencies such as uneven equipment quality caused by the rush of photovoltaic power stations have begun to plague photovoltaic companies and make photovoltaic companies "worse worse."
As the inspection center of the entire photovoltaic power station, the inverter is used for DC components at the top and grid-connected equipment at the bottom. Basically, all power station parameters can be detected by the inverter. It is the key equipment of the photovoltaic power station. Reports issued by Beijing Jianheng Certification Center, TUV Rheinland Group and other industry research institutions show that, in addition to the controllable factors in the installation process, more accidents of photovoltaic power plants occur in the boosting and heavy current parts, and the quality of photovoltaic power plant components accounts for The overall failure rate is 50%, and among them, inverters and combiner boxes have become the most frequent link of accidents.
The boom in photovoltaic installations in the past two years has brought about a substantial increase in the demand for photovoltaic modules and photovoltaic electrical appliances. Many manufacturers rushed to it, and the lack of industry standards at that time led to uneven electrical products. Even today, the quality of products in the photovoltaic industry is still uneven. Some manufacturers even start to market when the equipment testing technology and process cannot be successfully completed, which is unpredictable. The second is that the AC power is small and large. The AC power on the nameplate of the inverter cabinet door produced by some manufacturers is 200KW (kilowatt), while the module in the cabinet is marked with 150 kW, which does not meet the power station. The product does not even have an operating manual, and faults cannot be avoided.
At the same time, the surplus of photovoltaic modules has caused low-price competition, and inverters and other equipment also have such problems, leading to continuous occurrence of photovoltaic power station accidents.
Good photovoltaic modules are critical to the impact of photovoltaic power plants, otherwise the price of module repair and replacement will be a large amount of expense. SAFESAVE's inverter accessories are all internationally well-known brands, and the selection of specifications must be particularly cautious, leaving margins. For example, when selecting, the principle is based on the characteristics of the load. Resistive loads (such as incandescent bulbs) use correction waves, and inductive loads (such as motors) use sine wave inverters. The prices of the two inverters are very different.
Note: For example, some household appliances such as light bulbs, TVs, computers, rice cookers and other household appliances use the same correction wave as the sine wave. The influence of the correction wave is not great. The correction wave can be selected when considering the cost. Ordinary air conditioner (Note: 1P air conditioner is equal to 735W. Correctly we need to calculate 800W. Also note that it may sometimes be a large 1P air conditioner that will reach 1000W or less. We estimate that it is 850W) The instantaneous power of electric motors, refrigerators and other appliances. It is calculated by 3-5 times of the rated power. Generally, we recommend sine wave products to be calculated by 3 times (if 2P air conditioner is equal to 1500W, we recommend 4500W, but our 4000W products can also be driven because of the peak value of our products. It is 6000-8000W, the peak value is equal to the highest value of the instantaneous power of the impact). If the correction wave is to be driven, we need to calculate it by 5-7 times, but it will damage the electrical appliance itself. We generally do not recommend customers to use it.
In the industrial field, sine waves are generally used more, and sine waves are divided into high frequency and power frequency.
High-frequency inverters generally use magnetic cores or amorphous ferrous inverters with the same power in volume and weight that are much smaller than industrial frequency inverters. In addition, the industrial frequency inverter is large, heavy, and low in efficiency. It is very difficult to make a high-quality sine wave inverter that is exactly the same as the mains. The high frequency inverter can easily synthesize a sine wave through pulse width modulation technology.