On some occasions, there is the need to ensure that the load have to guarantee continuously inside of electrical applications, sometimes customers will find the UPS frequently occurs DC BUS appears high protection, or negative work protection. Some customers will conclude that the quality problems of the UPS. In fact, in most cases, this is followed by a motor class load phenomenon. In industrial applications, the motor is in the form of a load. When a key link in the industrial application must have a high enough level of power protection, the match of uninterrupted power supply and motor load is a key consideration factor. Usually, UPS is designed to protect critical IT equipment, IT class equipment features of the design based on the main circuit structure, such as the current IT equipment uses the switching power supply. And the EU regulations 75W more than the equipment must have a power factor correction. UPS main face load with a power factor correction usually features a power factor close to 1 constant power load.
UPS Systems Reliability
Either the PFC switching power supply or the pulse wave rectifier power supply, the real part of its power can only be positive, the energy will not be anti-irrigation back to the mains and therefore more importance in the design of the online ups systems is in the constant power load reliability, as well as with the nonlinear rectifier load harmonic control capabilities, as well as the voltage steady precision and dynamic recovery speed, without special requirements with the ability of energy feedback. Especially when there are a large number of intelligent designs in the UPS, it will tend to the energy from the load back to the DC bus of the UPS as a fault condition to be treated. With motor class load, motor renewable electricity generation energy is easy to trigger the conditions of UPS protection.
UPS Structure
On the other hand, UPS circuit architecture structure is the structure of the rectifier + battery boost + inverter, a large part of the UPS rectifier and battery boost part are using boost or deformation circuit energy only from the City the flow of electricity and the battery to the DC bus, but cannot reverse flow. Even though the software allows energy feedback, but when the energy feedback occurs, the energy stored in the DC bus, resulting in elevated DC bus, it will eventually lead to the UPS tripping. Motor load characteristics common IT equipment switching power supply is completely different, the performance of the start / brake and many other state, and there will be a very big difference, as the motor behind the load carried by different completely unlike IT class switching power supply as only uninstall. So the specific solutions also need to consider the motor behind the load carried by the case to be processed separately.
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