Multi-gun asynchronous charging device and method suitable for multi-pack battery replacement heavy truck

Abstract

The invention relates to a multi-gun asynchronous charging device and method suitable for a multi-pack battery changing heavy truck, the multi-gun asynchronous charging device comprises a charging host, a battery changing system end and a vehicle end, the battery changing system end comprises a plurality of battery boxes, a battery changing system end high-voltage box and a battery changing connector, and the vehicle end comprises a vehicle end high-voltage box. A plurality of battery boxes are connected in series and in parallel to form n sets of branch batteries, each set of branch batteries is provided with a corresponding charging circuit and a corresponding charging loop on a corresponding battery changing system end high-voltage box and a corresponding vehicle end high-voltage box, a three-level energy management framework is formed through an MBMU, n SBMUs, an HVB and a CSU in each battery box, and meanwhile a plurality of charging hosts are integrated. And each charging host is in charging communication with the corresponding branch battery SBMU, so that multi-gun multi-host simultaneous charging or asynchronous charging is realized, the charging power is increased, and the charging efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of heavy truck charging, and more specifically, to a multi-gun asynchronous charging device and method applicable to multi-pack battery swapping heavy trucks. Background Art

[0002] During the charging process of electric vehicles, usually each electric vehicle has a charging socket, and the charging pile has a charging gun with a connecting wire. The electric vehicle is charged by inserting the charging gun into the charging socket. However, since battery swapping heavy trucks generally operate continuously under high load for a long time and consume a large amount of electricity, large-capacity batteries need to be configured. Their batteries are often composed of multiple battery boxes connected in series and parallel to form a multi-branch battery system. Multiple battery branches are then aggregated into a single-branch or double-branch output / input in the high-voltage box and connected to the charging pile for charging. This method can only support single-gun or double-gun charging by one charging pile (charging host). Each charging host has limited charging capacity. When charging, after the charging current is evenly divided among multiple branches, the charging current obtained by each branch becomes smaller. In the case where heavy trucks generally need to be equipped with large-capacity batteries, the charging speed is too slow, seriously affecting the operation efficiency. Summary of the Invention

[0003] The purpose of the present invention is to provide a multi-gun asynchronous charging device and method applicable to multi-pack battery swapping heavy trucks to solve the above problems.

[0004] The present invention adopts the following technical solutions: A multi-gun asynchronous charging device applicable to multi-pack battery swapping heavy trucks, the multi-gun asynchronous charging device includes a charging host, a battery swapping system end, and a vehicle end. The battery swapping system end includes a plurality of battery boxes, a high-voltage box at the battery swapping system end, and a battery swapping connector. The vehicle end includes a high-voltage box at the vehicle end. The plurality of battery boxes are connected in series and parallel to form n sets of branch batteries. There are n sets of charging circuits in the high-voltage box at the battery swapping system end. Each set of charging circuits includes a pair of main circuit output ports, a high-voltage DC positive contactor, a high-voltage DC negative contactor, a fuse, and a current sensor. There are n sets of charging circuits in the high-voltage box at the vehicle end that cooperate with the n sets of charging circuits. Each set of charging circuits includes a charging socket, a pair of charging contactors, and a battery swapping connection input port. Each set of branch batteries corresponds to a set of charging circuits and a set of charging circuits. The charging host is at least n charging hosts, and each charging host is provided with a charging gun connected to the charging socket.

[0005] The multi-gun asynchronous charging device further includes an energy management architecture. The energy management architecture forms a three-level architecture by one MBMU, n SBMUs, one HVB, and CSU in each battery box. Among them, MBMU is the main battery management unit, SBMU is the slave battery management unit, HVB is the high-voltage electricity monitoring system, and CSU is the battery cell monitoring unit of the battery.

[0006] The MBMU is at the first level of the energy management control architecture and is responsible for the overall coordination within the battery system and external information interaction; each SBMU corresponds to a set of branch batteries. The SBMU is at the second level of the energy management control architecture and is responsible for monitoring the status of the corresponding branch batteries; the HVB is at the second level of the energy management control architecture and is responsible for high-voltage sampling of each charging circuit in the high-voltage box, controlling the charging contactor, and transmitting the information to the SBMU; the CSU in each battery box is at the third level of the energy management control architecture and is responsible for monitoring the status information of the corresponding branch batteries, and performing information sampling transmission and balancing actions of the corresponding branch battery system according to the request of the SBMU.

[0007] Furthermore, the vehicle-end high-voltage box further includes an output port for the vehicle load.

[0008] Furthermore, the MBMU is an MBMU control board, which is installed in the high-voltage box of the battery swapping system or at the vehicle end. The n SBMUs are n SBMU control boards, which are installed in the high-voltage box at the battery swapping system end. The HVB is an HVB control board, which is installed in the vehicle-end high-voltage box.

[0009] Furthermore, the MBMU can be integrated into the vehicle domain control unit.

[0010] A multi-gun asynchronous charging control method applicable to multi-pack battery swapping heavy trucks. For multi-gun asynchronous charging, different charging hosts are used. Each SBMU of each set of branch batteries corresponds to a charging host. The MBMU control board is responsible for overall coordination of the charging process. The specific control strategy is as follows: Step 1: Plug in the gun. Insert the charging gun of the charging host into the charging socket. Each SBMU sends the gun plug-in information to the MBMU. The MBMU determines whether the charging is at the vehicle end or at the battery swapping station end and starts the charging process.

[0011] Step 2: The MBMU identifies n sets of branch batteries based on the information sent by the SBMUs, and the MBMU control board identifies that m charging guns are inserted.

[0012] Step 3: Each SBMU sends the maximum allowable charging power Pi to the MBMU, and at the same time, each charging gun sends the maximum charging power Pj that it can provide.

[0013] Step 4: The MBMU selects the minimum value P of Pi described in Step 3 i-min , calculates that the maximum allowable charging power of the entire system is P i总 =n*(P i-min ), the MBMU sums up the Pj sent by all charging guns to get , and finally calculates that the maximum allowable total charging power is P i总 and P j总 take the minimum value. The calculation formula is: .

[0014] Step 5: Each SBMU sends the maximum allowable charging power P to the corresponding charging host k (k = 1, 2... m). If P 充总 = P j总 , then each SBMU sends the maximum allowable charging power P k = P j (k = j = 1, 2... m); if P 充总 = P i总 , then each SBMU sends the maximum allowable charging power P k = min(P 充总 / m, P j ) (k = j = 1, 2... m).

[0015] Step 6: According to the charging recognition result at the vehicle end or the battery swapping system end, close the corresponding contactors.

[0016] Step 7: Start charging, and calculate the charging power in real time according to the above Steps 4 to 5 and send it to the charger.

[0017] Step 8: Receive the stop charging instruction, go through the charging end process, and end the charging.

[0018] Further, in the above Step 6, if it is determined to be vehicle-end charging, the high-voltage DC positive contactor, high-voltage DC negative contactor, and charging contactor are closed successively. If it is determined to be charging at the battery swapping station end, the high-voltage DC positive contactor and high-voltage DC negative contactor are closed successively.

[0019] Further, in the above Step 7, it is continuously determined in real time whether a new charging gun is inserted or a charging gun in a certain charging circuit requires forced disconnection. If no new charging gun is inserted or the existing charging gun is not cut off, the charging continues in the existing state; if a new charging gun is inserted or the existing charging gun is cut off, then according to the situation of the newly added or reduced charging guns, the value of m is changed. The SBMU corresponding to the newly added charging pile communicates with the new charging pile and enters the charging process, or the SBMU corresponding to the reduced charging pile goes through the charging end process, recalculates Steps 4 and 5, and sends the new charging demand power to each charging host.

[0020] From the above description of the structure of the present invention, compared with the prior art, the present invention has the following advantages: 1. In the present invention, multiple battery packs are connected in series and parallel to form multiple sets of branch batteries. Each set of branch batteries corresponds to a set of charging circuits and charging loops, and multiple charging hosts are integrated. Each charging host communicates with the corresponding SBMU of the branch battery for charging, thereby realizing simultaneous charging or asynchronous charging of multiple guns and multiple hosts, increasing the charging power and improving the charging efficiency.

[0021] 2. Multiple charging hosts of the present invention can charge a single vehicle simultaneously or asynchronously. During the charging process, a new charging gun can be inserted or an existing charging gun can be removed by cutting off a part of the charging circuit according to the situation, without interrupting the charging process.

[0022] 3. During the charging process, the present invention adopts a unique charging power distribution algorithm, which can match the most suitable charging power according to the capabilities of the charging piles and the allowable charging powers of each power battery system. On the premise of not exceeding the limits, it provides the maximum charging power. At the same time, if a charging circuit is inserted or cut off during the charging process, the distribution can be adjusted in real time according to the situation. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the high-voltage electrical system architecture of the multi-gun asynchronous charging device of the present invention.

[0024] Figure 2 It is a schematic diagram of the three-level architecture of the energy management of the present invention.

[0025] Figure 3 It is a control flow chart of the multi-gun asynchronous charging of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The following describes the specific embodiments of the embodiments of the present invention with reference to the drawings.

[0027] Refer to Figure 1 , a multi-gun asynchronous charging device applicable to multi-pack battery-swap heavy trucks. The multi-gun asynchronous charging device includes a charging host, a battery-swap system end, and a vehicle end. The battery-swap system end includes a plurality of battery boxes, a high-voltage box at the battery-swap system end, and a battery-swap connector. The vehicle end includes a high-voltage box at the vehicle end. The high-voltage box at the battery-swap system end and the high-voltage box at the vehicle end are connected through the battery-swap connector.

[0028] Refer to Figure 1 and Figure 2 , the whole set of batteries is composed of a plurality of battery boxes connected in series and parallel to form n sets of branch batteries. There are n sets of charging circuits in the high-voltage box at the battery-swap system end. Each set of charging circuits includes a pair of main circuit output ports, a high-voltage DC positive contactor, a high-voltage DC negative contactor, a fuse, and a current sensor. In this embodiment, three sets of branch batteries are taken as an example, that is, there are 3 sets of charging circuits in the high-voltage box at the battery-swap system end. There are three pairs of main circuit output ports, three high-voltage DC positive contactors, three high-voltage DC negative contactors, three fuses, and three current sensors in the high-voltage box at the battery-swap system end.

[0029] Refer to Figure 1, there are n sets of charging circuits in the vehicle-end high-voltage box, which cooperate with n sets of charging loops. Each set of charging loop includes a charging socket, a pair of charging contactors, and an input port for battery swapping connection. Each set of branch batteries corresponds to a set of charging circuits and a set of charging loops. The charging host is at least n charging hosts, and each charging host is provided with a charging gun connected to the charging socket. In this embodiment, there are three sets of charging loops in the vehicle-end high-voltage box, and the charging hosts are at least three charging hosts. The vehicle-end high-voltage box also includes an output port for the whole vehicle load.

[0030] Referring to Figure 1 and Figure 2 , this system architecture can select a multi-pack battery system according to the actual vehicle usage requirements. For example, if the mileage requirement is short, a single-branch or double-branch battery system can be selected, and the corresponding SBMU is reduced. If the process requirement is long, a three-branch battery system can be selected. The entire battery swapping system has a universal interface and a universal structure, which is convenient for battery swapping. When the battery needs to be charged, the swapping connector of a certain branch can be separately connected to the charging pile to realize charging the battery of that branch alone, which can effectively shorten the charging time. For example, when the original three-branch battery system is charged with two DC guns according to the national standard, due to the limitation of the charging pile, the maximum charging current is 400A. When using this solution to charge each branch separately, the maximum charging current of each branch is 250A, and the total maximum charging current of the three branches can reach 750A, greatly shortening the battery charging time.

[0031] Referring to Figure 1 and Figure 2 The multi-gun asynchronous charging device of the present invention further includes an energy management architecture, which is formed by a three-level architecture including an MBMU, n SBMUs, an HVB, and a CSU in each battery box. Among them, the MBMU is the main battery management unit, the SBMU is the slave battery management unit, the HVB is the high-voltage power monitoring system, and the CSU is the battery cell monitoring unit.

[0032] The MBMU is at the first level of the energy management control architecture, responsible for the overall coordination inside the battery system and external information interaction, and controlling the operation of the entire battery system according to external requests. The MBMU can be an independent MBMU control board or integrated into the vehicle domain control unit. In this embodiment, it is an MBMU control board, which is installed in the high-voltage box of the battery swapping system or at the vehicle end.

[0033] The MBMU controls three branch battery systems through three SBMUs respectively. In actual use, different branches can be configured according to the situation, corresponding to different SBMUs. The SBMU is at the second level of the energy management control architecture and is responsible for monitoring the status of the corresponding branch battery, including the estimation of the SOC / SOH of the branch battery, balancing, SOP prediction, contactor control and status monitoring, fault diagnosis, etc., and controls the operation of the branch battery system according to the control instructions requested by the MBMU and / or the station terminal. The MBMU realizes program generalization through the encoding method of the SBMU. After the SBMU is encoded, it monitors the battery status information through the CSU in the corresponding branch battery box according to its respective encoding and transmits it to the MBMU, and at the same time executes the control instructions of the MBMU, and performs corresponding high-voltage sampling in the high-voltage box through the HVB of the same layer. When charging at the station terminal, each SBMU realizes the charge and discharge management of the corresponding branch battery by controlling the high-voltage DC positive and negative contactors of the corresponding branch. Through this architecture, centralized control and distributed execution at the vehicle end and decoupled distributed control of the station terminal system are realized. In this embodiment, the SBMU is preferably three SBMU control boards, which are arranged in the high-voltage box at the battery swapping system end.

[0034] The HVB is at the second level of the energy management control architecture and is responsible for high-voltage sampling in the high-voltage box, charging contactor control, and transmitting it to the SBMU. In this embodiment, the HVB is preferably one HVB control board, which is arranged in the high-voltage box at the vehicle end.

[0035] The CSU of the battery is at the third level of the energy management control architecture and is responsible for monitoring the status information such as the temperature and voltage of the corresponding branch battery, and performing the sampling transmission and balancing actions of the corresponding branch battery system information according to the request of the SBMU.

[0036] Refer to Figures 1 to 3 , a multi-gun asynchronous charging control method applicable to multi-pack battery swapping heavy trucks. In the multi-gun charging of the present invention, different charging hosts are used. Each set of main control SBMUs of the branch batteries in this solution corresponds to a charging host, and the MBMU is responsible for overall coordinating the charging process. The specific control strategy is as follows: Step 1: Plug in the gun. Insert the charging gun of the charging host into the charging socket. Each SBMU sends the gun insertion information to the MBMU, and the MBMU judges whether the charging is vehicle-end charging or charging at the battery swapping station, and starts to enter the charging process.

[0037] Step 2: The MBMU identifies n sets of branch batteries according to the information sent by the SBMU, and the MBMU control board identifies that m charging guns are inserted.

[0038] Step 3: Each SBMU sends the maximum allowable charging power Pi to the MBMU, and at the same time each charging gun sends the maximum charging power Pj that can be provided.

[0039] Step 4: The MBMU selects the minimum value P of Pi described in Step 3 i-min, Calculate that the maximum allowable charging power of the entire system is P i总 =n*(P i-min ), The MBMU sums up the Pj sent by all charging guns to get , In summary, the calculated maximum allowable total charging power is P i总 and P j总 Take the minimum value, and the calculation formula is: .

[0040] Step Five, each SBMU sends the maximum allowable charging power P k (k = 1, 2... m) to the corresponding charging host. If P 充总 =P j总 , then each SBMU sends the maximum allowable charging power P k =P j (k = j = 1, 2... m) to the corresponding charging host; if P 充总 =P i总 , then each SBMU sends the maximum allowable charging power P k =min(P 充总 / m, P j ) (k = j = 1, 2... m).

[0041] Step Six, according to the charging recognition result at the vehicle end or the battery swapping system end, close the corresponding contactors. If it is judged as vehicle-end charging, then successively close the high-voltage DC positive contactor, high-voltage DC negative contactor, and charging contactor. If it is judged as charging at the battery swapping station end, then successively close the high-voltage DC positive contactor and high-voltage DC negative contactor.

[0042] Step Seven, start charging, calculate the charging power in real time according to Steps Four to Five above and send it to the charger. During the charging process, judge in real time whether there is a new charging gun inserted or a charging gun in a certain charging circuit requests to be forcibly disconnected. If there is no new charging gun inserted or the existing charging gun is not cut off, then continue charging in the existing state; if there is a new charging gun inserted or the existing charging gun is cut off, then according to the situation of the newly added or reduced charging guns, change the value of m, and the SBMU corresponding to the newly added charging pile communicates with the new charging pile to enter the charging process, or the SBMU corresponding to the reduced charging pile goes through the charging end process, recalculate Steps Four and Five, and send the new charging demand power to each charging host.

[0043] Step Eight, receive the stop charging instruction, go through the charging end process, and end the charging.

[0044] The above is only the specific implementation manner of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantive modification made to the present invention using this concept shall fall within the scope of infringement of the protection of the present invention.

Claims

1. A multi-gun asynchronous charging device suitable for heavy trucks with multiple battery swaps, the multi-gun asynchronous charging device comprising a charging host, a battery swap system end and a vehicle end, characterized in that: The battery swap system end includes a plurality of battery boxes, a battery swap system end high-voltage box and a battery swap connector, the vehicle end includes a vehicle end high-voltage box, and a plurality of battery boxes are connected in series and parallel to form n sets of branch batteries. The battery swap system end high-voltage box is provided with n sets of charging circuits, each set of charging circuits includes a pair of main circuit output ports, a high-voltage DC positive contactor, a high-voltage DC negative contactor, a fuse and a current sensor, and the vehicle end high-voltage box is provided with n sets of charging circuits that cooperate with the n sets of charging circuits, each set of charging circuits includes a charging socket, a pair of charging contactors, and a battery swap connection input port, each set of branch batteries corresponds to a set of charging circuits and a set of charging circuits, and the charging host is at least n charging hosts, and each charging host is provided with a charging gun connected to the charging socket; The multi-gun asynchronous charging device also includes an energy management architecture, which is composed of a MBMU, n SBMUs, a HVB, and a CSU in each battery box to form a three-level architecture, wherein the MBMU is a master battery management unit, the SBMU is a slave battery management unit, the HVB is a high-voltage power monitoring system, and the CSU is a battery cell monitoring unit; MBMU is at the first level of the energy management control architecture and is responsible for overall coordination within the battery system and external information interaction; Each SBMU corresponds to a set of branch batteries. The SBMU is at the second level of the energy management control architecture and is responsible for status monitoring of the corresponding branch batteries. HVB is at the second level of the energy management control architecture, responsible for high-voltage sampling and charging contactor control of each charging circuit in the high-voltage box, and transmits it to the SBMU; The CSU in each battery box is at the third level of the energy management control architecture, responsible for monitoring the status information of the corresponding branch battery, and executing the corresponding branch battery system information sampling, transmission and balancing actions according to the SBMU request.

2. According to claim 1, a multi-gun asynchronous charging device suitable for multi-pack battery replacement heavy trucks is characterized by: The vehicle-end high-voltage box also includes a vehicle load output port.

3. According to claim 1, a multi-gun asynchronous charging device suitable for multi-pack battery replacement heavy trucks is characterized by: The MBMU is an MBMU control board, which is installed in the high-voltage box of the battery swapping system or the vehicle end. The n SBMUs are n SBMU control boards, which are installed in the high-voltage box of the battery swapping system end. The HVB is an HVB control board, which is installed in the high-voltage box of the vehicle end.

4. According to claim 1, a multi-gun asynchronous charging device suitable for multi-pack battery replacement heavy trucks is characterized by: The MBMU can be integrated into the vehicle domain control unit.

5. A multi-gun asynchronous charging control method suitable for multi-pack battery replacement heavy trucks, characterized by: The multi-gun asynchronous charging device according to claim 1, 2, 3 or 4 is adopted. The multi-gun asynchronous charging is performed by different charging hosts. The SBMU of each branch battery corresponds to a charging host. The MBMU control board is responsible for the overall coordination of the charging process. The specific control strategy is as follows: Step 1: Plug the charging gun of the charging host into the charging socket. Each SBMU sends the plug-in information to the MBMU. The MBMU determines whether the charging is for vehicle-side charging or battery swap station-side charging, and starts the charging process. Step 2: MBMU identifies that there are n sets of branch batteries according to the information sent by SBMU, and the MBMU control board identifies that m charging guns are inserted; Step 3: Each SBMU sends the maximum allowed charging power Pi to the MBMU, and each charging gun sends the maximum charging power Pj that can be provided; Step 4: MBMU selects the minimum value P of Pi described in step 3 i-min , calculate the maximum allowable charging power of the entire system as P i总 =n*(P i-min ), MBMU sums up the Pj sent by all charging guns to get , the maximum allowable total charging power is P i总 With P j总 Take the minimum value, the calculation formula is: ; Step 5: Each SBMU sends the maximum allowed charging power P to the corresponding charging host. k (k=1, 2...m), if P 充总 =P j总 , each SBMU sends the maximum allowable charging power P to the corresponding charging host k =P j (k=j=1, 2...m); if P 充总 =P i总 , each SBMU sends the maximum allowable charging power P to the corresponding charger k =min(P 充总 / m ,P j )(k=j=1,2...m); Step 6: According to the charging identification result of the vehicle or battery swapping system, close the corresponding contactor; Step 7, start charging, calculate the charging power in real time according to the above steps 4 to 5 and send it to the charger; Step 8: After receiving the stop charging instruction, follow the charging end process to end charging.

6. According to claim 4, a multi-gun asynchronous charging control method suitable for multi-pack battery replacement heavy trucks is characterized by: In step six, if it is determined that the charging is at the vehicle end, the high-voltage DC positive contactor, the high-voltage DC negative contactor and the charging contactor are closed successively; if it is determined that the charging is at the battery swap station end, the high-voltage DC positive contactor and the high-voltage DC negative contactor are closed successively.

7. According to claim 4, a multi-gun asynchronous charging control method suitable for multi-pack battery replacement heavy trucks is characterized by: In step seven, it is determined in real time whether a new charging gun is inserted or a charging gun in a charging route requires forced disconnection. If no new charging gun is inserted or an existing charging gun is disconnected, charging in the current state continues; if a new charging gun is inserted or an existing charging gun is disconnected, the value of m is changed according to the addition or reduction of charging guns, and the SBMU corresponding to the newly added charging pile communicates with the new charging pile to enter the charging process or the SBMU corresponding to the reduced charging pile ends the charging process, and steps four and five are recalculated, and the new charging demand power is sent to each charging host.

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