Big move to shun power outages: fast on/off-grid switching tech


It is common sense that you should constantly save the files you are editing to prevent data loss if the PC stops working due to a power failure. From an industrial point of view, more and more companies are evolving towards automation and intelligence, with programs moving machinery to control production lines. An unanticipated power outage can greatly affect the work of a factory, affecting production planning and delivery, and possibly causing damage to the machine, resulting in losses. From the company's point of view, the utility power failure affects the company's work progress, and the PC is too late to save the status of the project being worked on, which will affect data preservation and cause data information loss or leakage, resulting in incalculable losses.


However, what is less known is that the PC can only work for about 16ms when the mains power is lost. Fast on/off-grid switching technology can achieve fast on/off-grid switching within 10ms, timely power supply to the PC and other types of equipment to avoid the above situation. 


· How is on/off-grid switching achieved?

Graphic 1 shows the common topology of an energy storage system.

The PCS obtains grid information through grid-side sampling points and switches to off-grid through control switch K1.


Graphic 1: common topology of an energy storage system


People blink for 200-400ms. 10ms delay is much faster than the blink of an eye. Kehua has more than 30 years of power electronic conversion technology precipitation, in the field of fast on/off-grid switching has long obtained the relevant patents (specifically?). Kehua has been steadily applied in the field of UPS for a long time. Therefore, Kehua is able to realize the switching within 10ms, which means that Kehua has already matured and completed the commercial application of this technology.


· So, how does a proven fast off-grid switching solution work?

The following is a comparison of a common solution and a state-of-the-art one on the market.

On grid——Off grid Common Solution


1. Controller detects grid anormally

2. controller controls switch K1 disconnection

3. controller sends message to PCS to change

 working mode

4. PCS essage and switches to off-grid mode


On grid——Off grid Kehua Solution


1. PCS detects grid anormally

2. PCS directly controls switch K1 disconnection

3. PCS switches to off-grid mode





It can be clearly seen that the common solution on the market is controlled by an external controller to switched on/off-grid mode, and the intermediate controller collects information, processes it, and controls the PCS and switch K1. This solution has a long transmission delay, and there is computational redundancy, and the switching time is greatly extended, so it is difficult to achieve the purpose of fast on/off-grid protection of data and information to guarantee production. 

Kehua's seamless switchingtechnology supports PCS of 500KW and below power section to sample AC side information and grid-side information directly, which can easily achieve the process of fast and off-grid switching. 


In conclusion, fast grid switching technology is one of the most advanced and effective energy storage technologies, and the application of this technology in energy storage products has an important risk control significance for commercial and industrial owners.

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