If it is necessary to add a generator as a backup power source in the UPS power supply system, the selection of the generator is particularly important. Because this system not only requires a high degree of automation for the generator set, but also requires the generator to adapt to the non-linear load characteristics of UPS. When the selection of diesel generator set and UPS is unreasonable, the phenomenon of generator set output voltage oscillation and current oscillation often occurs. What’s more serious is that the generator frequency (speed) oscillation may also occur. At this time, due to the regular fluctuation of load, the operation of the generator set will be strong and weak, and the vibration of the generator set will intensify, accelerating mechanical wear and even causing serious damage to the components. One of the most obvious characteristics of frequency oscillation is the regular fluctuation of generator operating noise, which must be highly valued. Of course, when the frequency and voltage oscillation of the generator have exceeded the working range of the UPS input, the UPS will also switch frequently, which will have a certain impact on the load. Generally speaking, in the capacity ratio relationship between the generator and UPS configuration, due to interference such as harmonic feedback and sudden changes in load current of UPS, the capacity of the generator needs to be 2-2.5 times the maximum load capacity of UPS. At the same time, other load factors carried by the generator should also be considered to determine its capacity according to specific circumstances. Of course, when selecting a generator set, it is not only necessary to consider the appropriate power matching, but also to understand the excitation type of the generator in order to better adapt to the needs of UPS (non-linear load).
Daily maintenance of UPS
With the increasing popularity of computers, the protective god of computers, UPS, has also been widely used, especially for large data centers. As a power guarantee, the UPS system is not allowed to have any faults. Scientific use and maintenance will extend the life of UPS and ensure that your UPS is always available! Here are some of my experiences for your reference.
1.Due to the fact that UPS is rarely turned on or off, many people overlook the correct sequence of turning it on and off. In fact, the manufacturer’s user manual provides detailed instructions for the corresponding operation steps. Generally speaking, we should follow the following principles. In order to avoid damage to the UPS caused by the surge current generated by the load at the moment of startup, the UPS should be powered first to ensure that it is in normal working condition, and then the loads should be turned on one by one. This avoids the impact of load current on the UPS and extends its service life. The shutdown sequence can be seen as the reverse process of the startup sequence, first shutting down the loads one by one, and then shutting down the UPS. Additionally, it should be noted that UPS should operate in inverter protection mode during normal use, and can be operated in bypass or shut down when not in use.