With state support for new energy photovoltaic industry has been rapid development, the industry increasingly stringent acceptance standards, maximize efficiency and safety has become a core issue of the owners and two power companies are concerned, and network anti-islanding protection device is an important control element for photovoltaic power generation security assurance. Its rationality and reliability are also very important. Many people in the photovoltaic industry may know that the rcx-9390D photovoltaic island protection device has a particularly good reputation. Also very large, as a member of the industry, of course, also used, and really understand why the rcx-9390D anti-islanding protection device is so popular, the following author will elaborate on the rational design of the next rcx-9390D anti-islanding protection device
First we look at the functional design of the rcx-9390D anti-islanding protection device
01. Overvoltage (trip)
02. Low Voltage (Tripping)
03. Frequency too high (trip)
04. Frequency is too low (trip)
05. Frequency mutation (trip)
06. Reverse power (trip)
07. External Link 1 (trip)
08. System Failure (Alarm/Trip)
09. Automatic pressure closing
10. High frequency fault recovery closing
11. Low frequency fault recovery closing
12. High-voltage fault recovery closing
13. Low frequency fault recovery closing
14. Quick break (trip)
15. Limited Speed Break (trip)
16 Overcurrent (trip)
17. Residual current protection (trip)
First, we look at the tripping function; overvoltage, low voltage, high frequency, low frequency, abrupt change of frequency, reverse power, three-phase current protection, residual current protection, this is easy to understand, that is, the photovoltaic system is in operation. The rcx-9390D anti-islanding protection device can immediately detect and send a trip command to the grid-connected switch to allow it to trip, thus ensuring the safety of the system and avoiding the explosion of the accident; then why design these functions? This requires in-depth understanding, first of all talk about high-frequency, low-frequency, high-voltage, low-voltage protection, because the photovoltaic generation with the strong light conditions, photovoltaic system frequency, voltage will also change, and the system can withstand The scope is one, if you do not control him, he will cause damage and impact on some equipment on the grid and photovoltaic side, but also seriously threaten the safety of the operation and maintenance personnel, and install rcx-9390D anti-islanding protection After installation, these problems will be solved fundamentally.
Second, we take a look at the closing function; there is pressure loss tripping, there is a pressure closing function; high frequency fault recovery closing, low frequency fault recovery closing, high pressure fault recovery closing, low frequency fault recovery closing, industry practitioners People may see that the rcx-9390D anti-islanding protection device has more high-frequency fault resuming closing, low-frequency fault resuming closing, high-voltage fault resuming closing, and low-frequency fault resuming closing closing compared to other products on the market. Function, but these four functions really help the distributed photovoltaic power plant solve a lot of troubles. Just mentioned above, the photovoltaic system may appear high-frequency, low-frequency, high-voltage and low-voltage trip in the system. Once the trip, the fault is lifted. Failure to close them in time will affect the overall efficiency of power generation. At the same time, manual closing will also increase the operating costs. The rcx-9390D anti-islanding protection device solves these problems well, resulting in high, low, and high frequencies. The low-voltage fault can be tripped in time. After the fault is removed, it can be closed in time, realizing the maximization of user interests.
Third, there may be many users who say that other manufacturers' equipment does not have a voltage-lost trip and does it have a press-closing function? Remember, do not think that the high, low frequency, high, low pressure fault recovery can be closed, because he is a loss of pressure trip, rather than high, low frequency, high, low voltage trip, the function of these two is not the same thing, so Never be deceived by unprofessional manufacturers.
Fourth, many users may ask why they cannot switch on after tripping of the current protection during the three segments. I once asked this question. Later, the rcx-9390D anti-islanding protection device R&D technology and I said that 1. The voltage is low. Mostly, the grid is in a fault state, the access point's power grid is disconnected, and the grid is under maintenance. When the inspection is completed, the power supply is resumed, and the switch can be automatically closed. 2. High voltage For photovoltaic power plants, the transient voltage of the power grid is often high, or lightning strikes and other reasons. However, the power grid is relatively stable and will return to normal in an instant, so the switch can be automatically closed. 3, high frequency and low frequency, this problem is also mostly the fluctuation of the power grid (does not rule out the transformer failure, in a project in Jilin, and after one month of grid-connected island protection device always high-frequency trip, after checking the reason is the transformer failure Therefore, according to the actual situation, the grid-connected switch can also reclose itself. 4, current quick-break protection, over-current protection and residual current protection. When over-current protection occurs, this generally causes over-current protection to be mostly caused by a two-phase or three-phase short circuit. This is a serious power failure and must be tripped and cannot be re-closed. The appearance of the residual current shows that the three-phase current appears unbalanced, and when the protection setting value is reached, the switch must also trip. Avoid causing big faults.
These solutions instantly made me understand their professionalism. Also let us understand the rationality of the rcx-9390D anti-islanding protection device design, it can be said that it is really from the perspective of safety, from the perspective of efficiency, standing on a professional point of view to solve the problem of photovoltaic grid connection, Using this product also really saved me a lot of things. The design of device functions does not require blind roots, but it requires meaningful solutions to practical problems. This requires understanding of the operating conditions of photovoltaics in order to design a reasonable product. This is also an anti-islanding protection device rcx-9390d. Why is such a good reason used in low voltage distributed photovoltaic systems?