This is not a recent day, received a message from a rural friend, he wants to build a 5kW photovoltaic power generation system on his roof, but when the inverter is selected, he is caught in the "choosing obsessive-compulsive disorder"!
He first compared the price of the same price in Taobao, the same brand price is a few hundred different, and did not find the official flagship store; then consulted in the WeChat circle of friends, several agents said that they are xx manufacturers directly take the goods belong to a certain place The total generation, but there are several total generations in one place. Who should I choose? In desperation, I contacted several manufacturers. Every family said that they are better than each other. The advantages are listed in a lot, but which one is better? Finally found the largest inverter company, but when the other party heard that only 5kW, simply say that you contact xx regional agent!
After some tossing, this friend is not a taste in the heart - why are the rural people choosing the inverter so difficult?
In fact, there are still many tricks for the choice of inverters in photovoltaic systems . It can be considered from these aspects: cost, efficiency and operational characteristics.
First, the cost often affects people's choice of space
For rural users, the construction of photovoltaic systems is not fashionable, the map is fresh, mostly from the perspective of financial investment, system costs often dominate the choice of people. This also provides opportunities for individual businesses to bring cheap inverters to market in order to occupy the market. In fact, it is no problem to be cheap, as long as cheap is not built on low quality. But in reality, cheap often equates with low quality paintings.
The photovoltaic inverters for household systems are string inverters, which are small in size and light in weight. They are easy to handle and install, do not require professional equipment and tools, and do not require a power distribution room. They are all installed next to the PV modules , and the cable should not be laid in a wide range, and the installation cost is relatively low.
Its cost is not external, so where is it? Certainly inside it, the inverter is composed of many components, such as IGBT, fuse, capacitor, sensor, relay, diode, microprocessor, segment, resistor, etc. Don't underestimate the difference between components of different brands of these components. Still very big. In addition, the panel processing mode of the inverter and the size of the display screen are also very different.
Second, the efficiency is king's photovoltaic power generation era, inverter efficiency should be so!
At the time of writing this article, Photovoltaics also consulted the mainstream inverter manufacturers in the industry. As far as the brochures are concerned, the maximum efficiency of each family can reach 98% or even higher. The efficiency of the inverter is the basic guarantee for the amount of photovoltaic power generation and user benefits. The difference in efficiency of inverters of different brands is mainly system optimization and line loss. The string inverters commonly used in user systems, each group of battery strings is input into an inverter, and the inverter separately performs MPPT on the input battery string to ensure that each string generates the maximum amount of power. Even if a certain string is disconnected due to insufficient solar radiation or due to a fault, the other strings are not affected and continue to generate electricity.
In practice, the only indicator to consider the efficiency of the inverter is the amount of power generation. For those companies that do EPC, to compare the inverters of two different brands, the same board is often used with a power inverter, but this comparison It is a method, but it is not absolutely accurate. Here we only say that the amount of power generated by the inverter screen is also man-made. The efficiency is also software-adjustable. The most accurate one is based on the meter. This is also the user wondering why the number on the inverter screen is different from the number displayed on the meter. Of course, this is not very common, but don't make a fuss when you encounter it. Therefore, when choosing the comparison, find the appropriate efficiency comparison method.
Third, master the operating characteristics of the inverter, and increase the power generation capacity of the inverter .
Above we mentioned that the inverter consists of so many components, the performance of these components determines the performance of the inverter. The inverter in the household system work generally has IP65 protection level, but it is not unexpected that it is "invulnerable" and "non-toxic and non-invasive".
The process of operating the inverter is an exothermic process. As the source continues to emit electricity, a large amount of heat is generated. This requires sufficient convection space around the inverter to dissipate the surrounding area. The heat, the household system is usually based on natural heat dissipation, and will not be equipped with a fan. The medium and large inverters are often equipped with a cooling fan.
Although the inverter has IP65 protection level, when you expose it to harsh environments for a long time, it also affects its service life and affects its power generation capacity. If you want the inverter to operate stably for 10 or 20 years, it is essential for its "care". Although the inverter room will not be configured on the household system, try not to expose it to the nature. Usually, a awning is placed on the top.
Fourth, the certification is complete as a standard of choice.
Regardless of whether the inverter is exported abroad or domestically, the country has strict standards for it. The most authoritative one in China is CQC certification. The project for special requirements must conform to the leader certification. When selecting, it can be used as a reference. .
In addition, the National Quality Inspection Center will conduct sampling inspections of different batches of inverter products for domestic inverter manufacturers every year, and will announce the results. If even the quality inspection department of the country can't get through the test, you dare to say that the inverter is reliable. Is it? This can also be used as a reference when selecting.
Here we will talk about these first. In general, the PV inverter should select the inverter according to the actual installation situation of the user, which not only saves engineering cost, simplifies installation conditions, shortens the installation cycle, but also can effectively improve the system power generation. Efficiency is summarized as the principle of high efficiency, reliability, and low cost. These three are closely combined. If a problem arises, the whole system will have a "short leg" phenomenon, and it is necessary to know that "one point is worth the price." Goods" market hidden rules.
SHENZHEN CHONDEKUAI TECHNOLOGY CO.LTD , https://www.szfourinone.com