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[YesAuto Electric Vehicle] Vehicles cannot be charged via fast charging piles. I wonder if pure electric car fans have encountered similar situations? Recently, this situation has also occurred in our work car. Looking at the forum, I found that more than one car friend encountered similar problems. Today we will take a look together, how to solve the charging failure of the vehicle? What caused this? If your car also encounters the same situation, you may wish to refer to our solutions.

● What should I do if I can’t charge quickly?

Previously, our work car suddenly failed to charge through the charging pile of the National Grid, but the charging pile itself is normal because other vehicles can be charged through this pile. In order to verify whether there is a problem with the vehicle, we went to the other two charging stations to try, and the results were the same: charging could not be started.

I believe that many car users have also encountered a situation where the vehicle cannot be charged. First of all, we can confirm whether the vehicle charging failure is caused by the failure of the charging pile. Obviously, the situation we encountered is not the failure of the charging pile, but the problem of the vehicle, so we Choose to go to the 4S shop to find a solution. We learned from the 4S shop after-sales personnel that the failure of vehicle charging may be due to software (vehicle charging protocol) issues. Generally, software updates are carried out during maintenance of pure electric vehicles. Therefore, there are few customers who upgrade the software separately, but we still require The 4S shop refreshed the charging software of our working car.

After the upgrade, we tried to fast charge the vehicle again. At this time, several national grid charging piles can charge the vehicle. If your car also cannot be charged by the State Grid charging pile, you may wish to go to the 4S shop to try to upgrade the charging system, which may solve your problem; in addition, the car owner can remind the 4S shop to check when the vehicle is undergoing routine maintenance/inspection Check whether the vehicle charging protocol needs to be updated, so as not to cause trouble due to software problems in the future.

In the car users forum, we can also see that more than one car owner has encountered the problem of fast charging and unable to charge, and some of them have also solved the problem by upgrading the software. In fact, the so-called upgrade software is to enable normal communication between the vehicle and the charging pile. Now that we talked about this issue today, we might as well talk about what the national standard charging protocol is, and what does the communication between the charging pile and the vehicle mean? ?

● What is the meaning of the national standard charging protocol/communication protocol?

First of all, why do charging piles and vehicles have a national standard charging agreement? The national standard charging protocol makes the charging interface and communication of different brands of pure electric vehicles have unified standards, which also makes charging services more standardized; vehicles and charging piles adopt the national standard charging protocol, so that different brands of vehicles can use various types Different public charging piles are used for charging to help further unify the market.

For example, almost all Android smartphones now use the Type-C charging interface, and many electronic devices that can be charged via USB also use the same charging interface. The purpose of this is to unify the standard. To achieve interoperability, “you can charge when you get the cable”, does this greatly improve the convenience of charging? Of course, the conditions for charging pure electric vehicles are much more complicated than charging mobile phones.

In addition, if the national standard charging protocol is not established, different brand models and charging piles may have different technical routes, which may lead to inconsistent safety; and the national standard charging protocol has unified requirements for fast charging interfaces and safety requirements. Including charging piles, the charging guns need to meet the requirements of no deformation at high temperature, no damage from falling or collision, and waterproof and dustproof. Therefore, in addition to compatibility, the national standard charging protocol can also play an important role in charging safety.

Specifically, our latest GBT27930-2015 national standard charging protocol has upgraded five national standards for vehicle charging interface and communication protocol, so as to achieve the purpose of software and hardware update and unification. For example, the national standard charging protocol adds functions such as temperature monitoring of the charging interface, electronic locks, insulation monitoring, and bleeder circuits.

With the hardware standard, the rest is the software part, which is what we call communication. In fact, we upgrade the software so that the charging pile and the car can communicate normally, otherwise the car will not be able to charge normally. To put it simply, communication is the process of continuous communication and information exchange between the car and the charging pile. The charging process can only be successfully completed by the two “language communication”, “mutual information” and “reporting each other”.

The general charging process can be divided into several steps: physical connection, low-voltage auxiliary power-on, charging handshake, charging parameter configuration, charging, and charging end. The physical connection is the easiest to understand, and it is also the basis for establishing charging. Different countries have different national standard charging protocols and different charging interface types. The charging port is matched with the charging gun, and the vehicle is inserted into the charging pile, which also establishes the basic physics. connection.

The low-voltage auxiliary power-on is the process of powering on the vehicle's BMS. Only when the BMS is powered on can further handshake and communication with the charging pile. Some friends who know pure electric vehicles may have heard of the term “handshake between the vehicle and the charging pile”. The “handshake” is actually the process of verifying the version between the BMS and the charging pile. At this time, the “communication process” produced by the two is called Message. We can understand the message as a kind of “communication language” stipulated in the national standard charging protocol. Only if the language is communicated, the communication will fail.

The two have confirmed that the version is the same through a handshake, and the next step can be communicated. In fact, in the real communication message, the content generated is very detailed and complicated. The BMS and the charging pile will communicate with each other more politely. For example, after the two handshake is successful, the BMS will send a request: I want to give you Can I send more detailed vehicle information? When the charger allows to receive information, the two can exchange further information.

During the vehicle charging process, the charging pile can display the vehicle battery type, power, voltage, current, temperature, and even battery production date, charging times and other information. These contents are synchronized to the charging pile by the BMS. During this process, the two will generate a large number of messages. If the communication between the vehicle and the charging pile does not match, of course the normal charging work cannot be completed.

Earlier we said that the complete charging process includes charging handshake, charging parameter configuration, charging, charging end and other steps. For the communication between the vehicle and the charging pile, each step is similar, but the specific content of the message is different. . For example, during the charging phase, the BMS will continue to synchronize the vehicle battery status with the charging pile; for example, at the end of the charging phase, the BMS will send a request: I don’t need to charge anymore, request to end the charging…

Of course, the above are all normal charging conditions. For charging failures, both the BMS and the charger have their own communication format and content. The so-called “error” means that the BMS or the charging pile reports where there is a problem and cannot be charged normally. If we encounter charging failures for many times, we can also ask the customer service about the error reason or the meaning of the fault code indicated by the charging pile, so that we can judge whether it is the charging failure caused by the charging pile problem or the vehicle problem.

For the national standard charging protocol, its actual content is much more than what we mentioned today, such as the communication rate, the determination of the message timeout, the determination of the maximum current output, the termination of the message, etc., there are also unified regulations. . In the final analysis, all these regulations are aimed at achieving unification, security, and interconnection. It is precisely because of such high-standard regulations that we can have a safe and convenient charging experience.

Is it important to optimize the charging experience? In the development of pure electric vehicles, “mileage anxiety” has always been a word that accompanies it. Now we have products with excellent endurance, such as Xiaopeng Motors P7, Tesla Model 3, etc., but is it enough to simply improve the vehicle's endurance? On this basis, improving the energy supplement system, enhancing the energy supplement experience, and improving the safety of charging must not be overlooked.

In terms of car companies, Tesla, Xiaopeng Motors, Weilai and other car companies have joined the ranks of self-built charging networks. In terms of national strategy, for example, in 2015 and 2019, the State Council both stated that by 2020, charging piles will meet the charging needs of 5 million electric vehicles. At the beginning of April 2020, China Southern Power Grid also announced that it would invest 25.1 billion yuan in the construction of charging facilities in the next four years, so as to achieve the goal of 10 times the current number of new charging piles in the next four years.

Based on the continuous expansion of basic charging facilities, our charging standards must be constantly unified and upgraded, because this can maximize the value of charging piles, ensure the safety of the charging process, and optimize the charging experience of users. Thanks to the national standard charging protocol for charging piles, it allows us to have a better car experience.

to sum up:

Finally, let’s go back to the first question. If your car also has the problem of fast charging and unable to charge, please refer to what we said. Go to the 4S shop to upgrade the charging software. In addition, remember to request during daily maintenance. The 4S shop has updated the version of the national standard charging protocol for vehicles. As for the meaning of the communication protocol between the charging pile and the vehicle, and the meaning of the communication message, I believe you also have a certain understanding. If you also know some knowledge about pure electric vehicles, you might as well share it with us in the comment area.