Vehicle-mounted charging device and charging control method thereof

Abstract

The invention provides a vehicle-mounted charging device and a charging control method thereof, and the device comprises a commercial power switching module, an AC / DC module, a DC / DC module, a battery pack interface, a storage battery interface, and a shunting regulation and control module. The mains supply switching module is connected with the alternating current side of the AC / DC module, and the direct current side of the AC / DC module is connected with the input end of the shunt regulation and control module; a first output end of the shunting regulation and control module is connected with a battery pack interface through a first branch; the battery pack interface is used for being connected with a battery pack; a second output end of the shunting regulation and control module is connected with a DC / DC module through a second branch, and the DC / DC module is connected with a storage battery interface; the storage battery interface is used for being connected with a storage battery.

Description

Technical Field

[0001] The present invention belongs to the technical field of vehicle-mounted charging, and in particular relates to a vehicle-mounted charging device and a charging control method thereof. Background Art

[0002] There are two batteries on an electric car, one is a storage battery and the other is a battery pack. Both storage batteries and battery packs are devices that convert chemical energy into electrical energy and are a reversible DC power supply. The storage battery has a small capacity and is used to supply power to the low-voltage electrical equipment of the vehicle at the beginning of the vehicle start. The battery pack has a large capacity and is used to ensure the normal driving of the vehicle after the vehicle is started.

[0003] The existing on-board charging device can only charge the battery pack, but cannot charge the storage battery. When the storage battery is low and needs to be charged, the battery pack needs to charge the storage battery after the vehicle is started. This charging method is inconvenient, especially when the battery pack and the storage battery are both low in power. Summary of the invention

[0004] In order to solve the above technical problems, the present invention discloses an on-board charging device. The on-board charging device is provided with a shunt control module which can selectively charge a battery pack or a storage battery as needed under the control of a control module.

[0005] The present invention discloses a vehicle-mounted charging device, comprising a mains power transfer module, an AC / DC module, a DC / DC module, a battery pack interface, a storage battery interface, and a shunt control module; the mains power transfer module is connected to the AC side of the AC / DC module, and the DC side of the AC / DC module is connected to the input end of the shunt control module; the first output end of the shunt control module is connected to the battery pack interface through a first branch; the battery pack interface is used to connect to the battery pack; the second output end of the shunt control module is connected to the DC / DC module through a second branch, and the DC / DC module is connected to the storage battery interface; the storage battery interface is used to connect to the storage battery. The mains power transfer module can be connected to the external mains power, so that the mains power can charge the battery pack and the storage battery through the mains power transfer module. The AC / DC module is used to convert the alternating mains power into the direct current power required by the battery pack, and the shunt control module is used to control the opening and closing states of the first branch and the second branch to charge the battery pack or the storage battery as needed. The DC / DC module is used to convert the direct current power converted by the AC / DC module or the direct current power provided by the battery pack into the direct current power required by the storage battery.

[0006] Furthermore, it also includes a monitoring module and a control module; the monitoring module is communicatively connected to the control module and sends the monitored data to the control module; the control module is connected to the shunt regulation module; the control module controls the shunt regulation module based on the data monitored by the monitoring module; the data is the status of the AC power transfer module, the current power of the battery, and the current power of the battery pack.

[0007] The present invention also provides a charging control method for a vehicle-mounted charging device. Based on the vehicle-mounted charging device of the present invention, the charging control method of the present invention can reasonably adjust the charging sequence based on the current power of the battery pack and the storage battery.

[0008] A charging control method for a vehicle-mounted charging device of the present invention is based on the vehicle-mounted charging device and comprises the following steps: Step S1: setting parameters; the parameters include the critical power of the battery pack, the discharge threshold of the battery pack, the safety lower limit value of the battery, and the safety value of the battery; Step S2: monitor the status of the mains power transfer module, the current power of the battery pack, and the current power of the storage battery; Step S3: Determine the charging subject based on the state of the mains power transfer module; Step S4: Charging control is performed based on the charging subject, the current power of the battery pack, and the current power of the storage battery.

[0009] Further, in step S3, If the AC power transfer module is in the connected state, the charging subject is the AC power connected by the AC power transfer module, and the AC power charges the battery pack and the storage battery respectively through the AC power transfer module; If the AC power adapter module is not connected, the battery pack is the main charging object.

[0010] Furthermore, in step S4, when the charging subject is the mains electricity, it is further determined whether the current power of the battery is less than the safety value of the battery. If the current power of the battery is less than the safety value of the battery, the second branch is adjusted by the shunt control module to charge the battery first until the current power of the battery is greater than or equal to the safety value of the battery. If the current charge of the battery is greater than or equal to the safety value of the battery, the first branch is controlled by the shunt control module to charge the battery pack, and when the current charge of the battery pack reaches the critical charge, the charging of the battery is started until the battery pack and the battery are fully charged.

[0011] Furthermore, in step S4, When the charging subject is a battery pack, it is further determined whether the current charge of the battery pack is greater than the discharge threshold of the battery pack; if the current charge of the battery pack is greater than the discharge threshold of the battery pack, the current charge of the battery is compared with the safety lower limit of the battery; if the current charge of the battery is less than or equal to the safety lower limit of the battery, the battery pack charges the battery through the first branch, the shunt control module, the second branch, the DC / DC module, and the battery interface until the current charge of the battery reaches the safety value of the battery.

[0012] Furthermore, in the process of the shunt control module controlling the first branch to charge the battery pack, the current state of the first branch is adjusted by comparing the current power of the battery pack with the critical power of the battery pack.

[0013] Furthermore, if the current charge of the battery pack is less than the critical charge of the battery pack, the first branch is in a high-current fast charging state; if the current charge of the battery pack is greater than or equal to the critical charge of the battery pack, the high-current fast charging state of the first branch is gradually adjusted to a low-current slow charging state.

[0014] Beneficial effects of the present invention: The monitoring module of the vehicle-mounted charging device of the present invention transmits the monitored data to the control module, and the control module processes the data and controls the shunt control module to control the first branch and the second branch, so as to reasonably charge the battery and the battery pack under appropriate conditions, ensuring that the vehicle-mounted charging device reasonably controls the charging of the battery pack and the battery according to the current power.

[0015] The charging control method of the present invention first determines the charging subject, and then selectively performs charging control according to the current power of the battery pack and the current power of the storage battery, so as to ensure balanced charging of the battery pack and the storage battery as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the vehicle-mounted charging device of the present invention; Figure 2 This is a flow chart of the vehicle charging control method of the present invention; Figure 3 When the mains power transfer module is connected, when the current power of the battery is less than the safety value of the battery, the schematic diagram of the mains power charging the battery; Figure 4 When the AC power transfer module is connected, and the current power of the battery is not less than the safety value of the battery, the schematic diagram of the AC power charging the battery pack; Figure 5 When the AC power transfer module is connected, when the current power of the battery pack is greater than the critical power, the schematic diagram of the AC power charging the battery pack and the storage battery; Figure 6This is a schematic diagram of the battery pack charging the storage battery when the AC power conversion module is not connected. DETAILED DESCRIPTION

[0017] The technical scheme in the embodiment of the present invention is described clearly and completely below in conjunction with the accompanying drawings in the embodiment of the present invention. In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention can also be implemented in other ways different from those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0018] The invention discloses a vehicle-mounted charging device, which can selectively charge a battery pack or a storage battery according to needs under the control of a control module by setting a shunt regulation module.

[0019] The vehicle-mounted charging device of the present invention includes a mains power conversion module, an AC / DC module, a DC / DC module, a battery pack interface, a storage battery interface, a shunt control module, a monitoring module and a control module. Figure 1 The AC power transfer module is connected to the AC side of the AC / DC module, and the DC side of the AC / DC module is connected to the input end of the shunt control module, as shown in FIG. Figure 1 As shown; the first output end of the shunt control module is connected to the battery pack interface through the first branch; the battery pack interface is used to connect to the battery pack. The second output end of the shunt control module is connected to the input end of the DC / DC module through the second branch. The output end of the DC / DC module is connected to the battery interface; the battery interface is used to connect to the battery.

[0020] The monitoring module is connected to the control module for communication, and sends the monitored data to the control module; the control module is connected to the shunt control module. The control module controls the shunt control module to charge the battery pack or storage battery based on the data monitored by the monitoring module. The data includes the status of the AC power transfer module, the current power of the storage battery, and the current power of the battery pack. The AC power transfer module can be connected to the external AC power so that the AC power can charge the battery pack and the storage battery through the AC power transfer module. The AC / DC module is used to convert the AC AC power into the DC power required by the battery pack, and the shunt control module controls the status of the first branch and the second branch to charge the battery pack or storage battery as needed. The DC / DC module is used to convert the DC power converted by the AC / DC module or the DC power provided by the battery pack into the DC power required by the storage battery.

[0021] A charging control method of the present invention is implemented based on the above-mentioned vehicle-mounted charging device, such as Figure 2 As shown, the charging control method includes the following steps: Step S1: setting parameters; the parameters include the critical power of the battery pack, the discharge threshold of the battery pack, the safety lower limit value of the battery, and the safety value of the battery.

[0022] Step S2: The monitoring module monitors the status of the AC power transfer module, the current power of the battery pack, and the current power of the storage battery, and transmits the above data to the control module.

[0023] Step S3: The control module determines the charging subject based on the state of the AC power conversion module; there are two charging subjects, namely AC power or battery pack.

[0024] If the AC power adapter module is in the connected state, it means that the external AC power is connected to the charging adapter module. That is, the charging subject is the external AC power, and the AC power charges the battery pack and the storage battery respectively through the vehicle-mounted charging device.

[0025] If the AC power conversion module is not connected, the battery pack will be the main charging body; when the conditions are met, the battery pack can charge the battery to ensure that the vehicle can start normally as much as possible.

[0026] Step S4: Based on the current power of the charging subject, the battery pack, and the current power of the storage battery, the control module controls the shunt control module to perform charging control; When the charging subject is the mains electricity, the specific charging principles and charging sequence of the battery pack and battery are as follows: First, determine whether the current battery power is less than the battery safety value. If the current power of the battery is less than the safe value of the battery, the control module adjusts the second branch through the shunt control module to a voltage suitable for the battery through the DC / DC module, and then charges the battery through the battery interface. The specific schematic diagram is as follows Figure 3 As shown, until the current power of the battery is equal to the safety value of the battery, and after the current power of the battery is equal to the safety value of the battery, the charging of the battery is temporarily stopped; Secondly, if the current power of the battery is not less than the safety value of the battery (including the situation where the current power of the battery is equal to the safety value of the battery after charging the battery), the control module controls the first branch through the battery pack interface to charge the battery pack through the shunt control module. The specific schematic diagram is as follows: Figure 4 As shown, when the current power of the battery pack reaches the critical power of the battery pack, the control module controls the shunt control module to charge the battery through the second branch, the DC / DC module, and the battery interface. The specific schematic diagram is as follows Figure 5 until the battery pack and the accumulator are fully charged.

[0027] In order to ensure the safety of the battery pack, the current state of the first branch is adjusted according to the current power of the battery pack. Specifically, the current state of the first branch is determined by comparing the current power of the battery pack with the critical power of the battery pack, and then the control module controls the shunt control module to adjust it.

[0028] Specifically, if the current charge of the battery pack is less than the critical charge of the battery pack, the first branch is in a high-current fast charging state; if the current charge of the battery pack is greater than or equal to the critical charge of the battery pack, the shunt control module gradually adjusts the high-current fast charging state of the first branch to a low-current slow charging state, and at the same time, the shunt control module gradually opens and adjusts the second branch to charge the battery.

[0029] When the AC power adapter module is not connected, the battery pack cannot be charged because it is not connected to the external AC power. Although the battery pack can charge the storage battery, when the current power of the battery pack is too low or the current power of the storage battery is not low (the storage battery has enough power to ensure that the vehicle can be started normally), the battery pack does not need to charge the storage battery.

[0030] When the charging subject is a battery pack, determining whether the current power of the battery pack is greater than the discharge threshold of the battery pack; If the current charge of the battery pack is greater than the discharge threshold of the battery pack, the battery pack can charge the battery, and then compare the current charge of the battery with the safety lower limit of the battery; if the current charge of the battery pack is less than or equal to the discharge threshold of the battery pack, the battery pack cannot charge the battery.

[0031] If the current power of the battery is less than or equal to the safety lower limit of the battery, the battery pack charges the battery through the first branch, the shunt control module, the second branch, the DC / DC module, and the battery interface until the current power of the battery reaches the safety value of the battery. The specific schematic diagram is as follows Figure 6 shown.

[0032] Otherwise, the battery pack does not charge the storage battery (the battery pack and storage battery maintain their current status).

[0033] Here is a specific example: Step S1: setting parameters; the critical power of the battery pack is 80% of the total power of the battery pack, the lower safety limit of the battery is 20% of the total power of the battery, the safety value of the battery is 50%, and the discharge threshold of the battery pack is 40%.

[0034] Step S2: monitor the status of the AC power transfer module, the current power of the battery pack, and the current power of the storage battery.

[0035] Step S3: Determine the charging subject based on the state of the mains power transfer module; If the AC power conversion module is in the connected state, the main charging body is the AC power; the AC power charges the battery pack and the storage battery respectively through the AC power conversion module.

[0036] If the AC power conversion module is not connected, the charging subject is the battery pack. The current power of the battery pack is used to determine whether the battery pack can supply power to the storage battery; the current power of the storage battery is used to determine whether the storage battery needs to be powered by the battery pack.

[0037] Step S4: Based on the charging subject, charging control is performed.

[0038] When the main power source is used for charging, the current power level of the battery is first determined; If the current charge of the battery is 10%, the current charge of the battery is lower than the safety lower limit of the battery. The control module controls the shunt regulation module to charge the current charge of the battery to 50% of the total charge of the battery (the safety value of the battery) through the AC power transfer module, AC / DC module, shunt regulation module, second branch, DC / DC module and battery interface. Then, the AC power is used to charge the battery pack through the AC power transfer module, AC / DC module, shunt regulation module, first branch and battery pack interface. This ensures that even if the charging of the AC power needs to be stopped temporarily, the battery and the battery pack are maintained at a certain charge as much as possible, thereby ensuring the normal operation of the vehicle.

[0039] If the current charge of the battery pack is 30%, when the battery pack is charged, the first branch is in a high-current fast-charging state. When the current charge of the battery pack reaches 80% (critical charge) of the total charge of the battery pack, the first branch is gradually adjusted from a high-current fast-charging state to a low-charge slow-charging state. At the same time, the storage battery continues to be charged through the second branch until both the battery pack and the storage battery are fully charged.

[0040] When the mains power is not connected, it is only necessary to determine whether the battery needs to be charged and whether the battery pack can meet the charging conditions required by the battery.

[0041] If the battery pack's current charge is 60% and the battery's current charge is 60%, the battery pack does not need to charge the battery. If the battery pack's current charge is 60% and the battery's current charge is 8%, the battery pack will charge the battery's current charge to 50% and then stop charging the battery. If the battery pack's current charge is 34%, the battery cannot be charged.

[0042] The monitoring module of the present invention monitors the access status of the AC power conversion module, the power of the battery pack, and the power of the storage battery respectively and transmits them to the control module. After the control module processes and analyzes the data, it controls the shunt control module to control the first branch and the second branch, thereby selectively charging the storage battery and the battery pack.

[0043] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Claims

1. A vehicle-mounted charging device, characterized in that: It includes a mains power conversion module, an AC / DC module, a shunt control module, a DC / DC module, a battery pack interface, and a battery interface; the mains power conversion module is connected to the AC side of the AC / DC module, and the DC side of the AC / DC module is connected to the input end of the shunt control module; the first output end of the shunt control module is connected to the battery pack interface through a first branch; the battery pack interface is used to connect to the battery pack; the second output end of the shunt control module is connected to the DC / DC module through a second branch, and the DC / DC module is connected to the battery interface; the battery interface is used to connect to the battery.

2. The vehicle-mounted charging device according to claim 1, characterized in that: It also includes a monitoring module and a control module; the monitoring module is communicatively connected to the control module and sends the monitored data to the control module; the control module is connected to the shunt regulation module; the control module controls the shunt regulation module based on the data monitored by the monitoring module; the data are the status of the AC power transfer module, the current power of the battery, and the current power of the battery pack.

3. A charging control method for a vehicle-mounted charging device, the charging control method being based on the vehicle-mounted charging device according to claim 2, characterized in that: The following steps are involved: Step S1: setting parameters; the parameters include the critical power of the battery pack, the discharge threshold of the battery pack, the safety lower limit value of the battery, and the safety value of the battery; Step S2: monitor the status of the mains power transfer module, the current power of the battery pack, and the current power of the storage battery; Step S3: Determine the charging subject based on the state of the mains power transfer module; Step S4: Charging control is performed based on the charging subject, the current power of the battery pack, and the current power of the storage battery.

4. The charging control method according to claim 3, characterized in that: In step S3, If the AC power transfer module is in the connected state, the charging subject is the AC power connected by the AC power transfer module, and the AC power charges the battery pack and the storage battery respectively through the AC power transfer module; If the AC power adapter module is not connected, the battery pack is the main charging object.

5. The charging control method according to claim 4, characterized in that: In step S4, when the charging subject is the mains electricity, it is further determined whether the current power of the battery is less than the safety value of the battery. If the current power of the battery is less than the safety value of the battery, the second branch is adjusted by the shunt control module to charge the battery after passing through the DC / DC module until the current power of the battery is equal to the safety value of the battery. If the current charge of the battery is greater than or equal to the safety value of the battery, the shunt control module controls the first branch to charge the battery pack, and when the current charge of the battery pack reaches the critical charge of the battery pack, the battery is charged through the second branch until the battery pack and the battery are fully charged.

6. The charging control method according to claim 4, characterized in that: In the step S4, When the charging subject is a battery pack, it is further determined whether the current charge of the battery pack is greater than the discharge threshold of the battery pack; if the current charge of the battery pack is greater than the discharge threshold of the battery pack, the current charge of the battery is compared with the safety lower limit of the battery; if the current charge of the battery is less than or equal to the safety lower limit of the battery, the battery pack charges the battery through the first branch, the shunt control module, the second branch, the DC / DC module, and the battery interface until the current charge of the battery reaches the safety value of the battery.

7. The charging control method according to claim 5, characterized in that: In the process of the shunt control module controlling the first branch to charge the battery pack, the current state of the first branch is adjusted by comparing the current power of the battery pack with the critical power of the battery pack.

8. The charging control method according to claim 7, characterized in that: If the current charge of the battery pack is less than the critical charge of the battery pack, the first branch is in a high-current fast charging state; if the current charge of the battery pack is greater than or equal to the critical charge of the battery pack, the high-current fast charging state of the first branch is gradually adjusted to a low-current slow charging state.

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