Battery power supply loop and motor home

Abstract

The utility model relates to a battery power supply loop and a motor home, and belongs to the technical field of motor home standby power supplies. The battery power supply loop comprises a battery interface connected with a battery, a charging interface and a load interface which are arranged in parallel, and a charging branch and a discharging branch which are arranged in parallel, the charging branch comprises a charging contactor and a charging diode which are connected in series, and the discharging branch comprises a discharging contactor and a discharging diode which are connected in series; the conduction direction of the charging diode is the same as the charging current direction, the conduction direction of the discharging diode is the same as the discharging current direction, and the charging branch and the discharging branch are connected in parallel and then connected in series with the charging interface and the load interface which are arranged in parallel. According to the utility model, the charging branch circuit composed of the charging contactor and the charging diode which are connected in series is connected in parallel with the discharging branch circuit composed of the discharging contactor and the discharging diode which are connected in series, so that the problems of battery charging and discharging faults and difficulty in actively cutting off fault current caused by breakdown of the charging diode and the discharging diode can be solved.

Description

Technical Field

[0001] The utility model relates to a battery power supply circuit and a recreational vehicle, belonging to the technical field of recreational vehicle backup power supplies. Background Art

[0002] With the improvement of living standards, traveling by RV has become a new trend. RV can not only solve the problem of long distance, but also bring a more comfortable experience. Lithium battery, as a common power source in RV, has higher energy density and longer service life than traditional lead-acid batteries. Lithium battery is not affected by "memory effect" and can usually last more charge and discharge cycles, so it is particularly important to pay attention to the charge and discharge circuit of lithium battery.

[0003] In recent years, scientific and technological personnel from all over the country have conducted research on the charging and discharging circuits of RVs from the technical means and have achieved certain results. For example, the Chinese utility model patent authorization announcement document with the authorization announcement number CN218733314U discloses a RV backup lithium battery electrical system, such as Figure 1 As shown, the system connects the charging relay 13 and the discharging relay 14 in series between the positive electrode of the battery and the positive electrode side of the charging circuit and the load circuit. The charging relay 13 is connected in parallel with the discharging diode 11 having the same conduction direction and the discharging current direction. The discharging diode 11 is used to form a discharging branch with the discharging relay 14; the discharging relay 14 is connected in parallel with the charging diode 12 having the same conduction direction and the charging current direction. The charging diode 12 is used to form a charging branch with the charging relay 13. The above discharging branch and charging branch not only realize the same charging and discharging port, but also when the battery is about to be overcharged, only the switch contact of the charging relay 13 needs to be disconnected, which does not affect the discharge of the battery through the discharging relay 14 and the discharging diode 11; when the battery is about to be under-voltage, only the switch contact of the discharging relay 14 needs to be disconnected, which does not affect the charging of the battery through the charging relay 13 and the charging diode 12.

[0004] Although the above scheme achieves the same charging and discharging of lithium batteries and disconnects the charging relay 13 when the battery is about to be overcharged, which does not affect the battery discharge, and disconnects the discharge relay 14 when the battery is about to be under-voltage, which does not affect the battery charging, in order to improve the charging efficiency, the current existing technology has higher and higher charging voltages for high-voltage DC charging piles to quickly fill the vehicle battery. For this scheme, if the charging diode 12 and the discharge diode 11 are broken down during high-voltage DC charging, it will cause the vehicle charging and discharging to fail, and the fault current cannot be cut off by the charging and discharging relays. Utility Model Content

[0005] The utility model aims to provide a battery power supply circuit and a motorhome, so as to solve the problem in the prior art that after the charging diode and the discharging diode are broken down, the vehicle charging and discharging faults are caused and the fault current is difficult to be actively cut off.

[0006] To achieve the above purpose, the solution of the utility model includes:

[0007] The utility model discloses a battery power supply circuit, comprising a battery interface for connecting a battery, a charging interface and a load interface arranged in parallel, and also comprising a charging branch and a discharging branch arranged in parallel, the charging branch comprising a charging contactor and a charging diode connected in series, and the discharging branch comprising a discharging contactor and a discharging diode connected in series; the conduction direction of the charging diode is the same as the direction of the charging current, and the conduction direction of the discharging diode is the same as the direction of the discharging current; after being connected in parallel, the charging branch and the discharging branch are connected in series with the charging interface and the load interface arranged in parallel.

[0008] Furthermore, the switch contacts of the charging contactor and the switch contacts of the discharging contactor are controlled by a battery management system.

[0009] Furthermore, it includes a BMS power supply circuit for powering a battery management system. The BMS power supply circuit is connected in parallel at both ends of the battery interface. The self-locking contactor in the BMS power supply circuit is connected in parallel with a self-resetting switch and then in series with a normally closed switch.

[0010] Furthermore, a normally closed switch and a self-resetting switch are arranged on the power supply box.

[0011] A motorhome comprises a battery power supply circuit, the battery power supply circuit comprises a battery, a charging interface and a load interface arranged in parallel, and also comprises a charging branch and a discharging branch arranged in parallel, the charging branch comprises a charging contactor and a charging diode connected in series, and the discharging branch comprises a discharging contactor and a discharging diode connected in series; the conduction direction of the charging diode is the same as the direction of the charging current, and the conduction direction of the discharging diode is the same as the direction of the discharging current; the charging branch and the discharging branch are connected in parallel and are connected in series with the charging interface and the load interface arranged in parallel.

[0012] Furthermore, the switch contacts of the charging contactor and the switch contacts of the discharging contactor are controlled by a battery management system.

[0013] Furthermore, it includes a BMS power supply circuit for powering a battery management system. The BMS power supply circuit is connected in parallel at both ends of the battery. A self-locking contactor in the BMS power supply circuit is connected in parallel with a self-resetting switch and then in series with a normally closed switch.

[0014] Furthermore, a normally closed switch and a self-resetting switch are arranged on the power supply box.

[0015] The beneficial effects of the utility model are:

[0016] The utility model is an improved invention. A battery power supply circuit of the utility model includes a battery interface for connecting a battery, a charging interface and a load interface arranged in parallel, and a charging branch and a discharging branch arranged in parallel, wherein the charging branch is composed of a charging contactor and a charging diode connected in series, and the discharging branch is composed of a discharging contactor and a discharging diode connected in series, the conduction direction of the charging diode is the same as the direction of the charging current, and the conduction direction of the discharging diode is the same as the direction of the discharging current, and the charging branch and the discharging branch are connected in parallel and connected in series with the charging interface and the load interface arranged in parallel. The charging branch composed of the charging contactor and the charging diode connected in series and the discharging branch composed of the discharging contactor and the discharging diode connected in series are connected in parallel. When charging, high voltage will not be directly applied to both ends of the diodes connected in series as in the prior art cited in the background technology. On the one hand, the circuit setting of the utility model makes the charging diode and the discharging diode not easy to be broken down; on the other hand, after the diode is broken down, the fault current can still be cut off by disconnecting the corresponding contactor, avoiding the problem that the battery charging and discharging fault caused by the breakdown of the diode and the fault current is difficult to be actively cut off, and at the same time, it has the advantage of simple circuit connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the electrical system of a RV backup lithium battery;

[0018] Figure 2 The utility model is a battery power supply circuit electrical system schematic diagram.

[0019] Description of reference numerals:

[0020] 11. Discharge diode; 12. Charging diode; 13. Charging relay; 14. Discharge relay; 21. Fuse; 22. Charging contactor; 23. Discharge contactor; 24. Self-locking contactor; 25. Normally closed switch; 26. Self-resetting switch; 27. Shunt; 28. Charging diode; 29. ​​Discharge diode. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0022] The idea of ​​the utility model is to provide a battery power supply circuit, which is used to realize that the charging and discharging branches are in the same port and are independent of each other without affecting each other. It includes a battery interface for connecting the battery, a charging interface and a load interface arranged in parallel, and a charging branch and a discharging branch arranged in parallel. The charging branch is composed of a charging contactor and a charging diode connected in series, and the discharging branch is composed of a discharging contactor and a discharging diode connected in series. The conduction direction of the charging diode is the same as the direction of the charging current, and the conduction direction of the discharging diode is the same as the direction of the discharging current. The charging branch and the discharging branch arranged in parallel are connected in series with the parallel charging interface and the load interface. When the battery is about to be overcharged, the switch contact of the charging contactor is disconnected, the switch contact of the discharging contactor is closed, and the load is powered by the discharging branch; when the battery is about to be over-discharged, the switch contact of the discharging contactor is disconnected, the switch contact of the charging contactor is closed, and the battery is charged using the charging interface. The switch contact of the charging contactor is disconnected, the switch contact of the discharging contactor is closed, or the switch contact of the discharging contactor is disconnected, and the switch contact of the charging contactor is closed to form a seamless switching of charging and discharging, which can prevent the battery from being overcharged or over-discharged. By arranging the charging and discharging branches in parallel, the charging and discharging branches are connected in the same port, and when the battery is about to be overcharged, the charging branch is disconnected without affecting the discharging branch, and when the battery is about to be over-discharged, the discharging branch is disconnected without affecting the charging branch.

[0023] Battery powered circuit example:

[0024] like Figure 2 The schematic diagram of the electrical system of a battery power supply circuit shown in the figure includes a power circuit and a battery management system (BMS) power supply circuit. The power circuit includes a battery, a charging branch, a discharging branch, a charging interface and a load interface. Among them, the charging contactor 22 is connected in series with the charging diode 28 to form a charging branch, and the discharging contactor 23 is connected in series with the discharging diode 29 to form a discharging branch. The conduction direction of the charging diode 28 is the same as the direction of the charging current, and the conduction direction of the discharging diode 29 is the same as the direction of the discharging current; the charging branch and the discharging branch are arranged in parallel, and the charging branch and the discharging branch arranged in parallel are connected in series with the charging interface and the load interface arranged in parallel; the battery, the charging and discharging branches arranged in parallel, the charging interface arranged in parallel and the load interface are connected in series in sequence; the charging interface is used to connect the charging gun to charge the load and the battery, and the load interface is used to connect the load that needs to be powered; when encountering the charging interface, the load can be powered by the charging interface and the battery can also be charged; when there is no charging interface, the load is powered by the battery.

[0025] The battery management system (BMS) power supply circuit includes a normally closed switch 25, a self-locking contactor 24, a self-resetting switch 26 and a BMS. After the self-resetting switch 26 and the self-locking contactor 24 are connected in parallel, they are connected in series with the normally closed switch 25. The BMS power supply circuit is connected in parallel at both ends of the battery interface. The self-locking contactor 24 is installed inside the power supply box, and the normally closed switch 25 and the self-resetting switch 26 are both installed on the power supply box. Installing the normally closed switch and the self-resetting switch on the power supply box can facilitate user operation.

[0026] The BMS self-power supply method is: when the normally closed switch 25 is not pressed, the self-reset switch 26 is pressed for a delay of 3s. After the BMS is powered on, a self-check is performed. If there is no abnormality in the self-check, the self-locking contactor 24 is controlled to be attracted. After ensuring that the self-locking contactor 24 is attracted, the self-reset switch 26 is released. At this time, the circuit of the self-locking contactor 24 is turned on, and the current passes through the normally closed switch 25, the self-locking contactor 24, and the BMS, thereby realizing the self-power supply of the BMS.

[0027] When the battery is not over-voltage or under-voltage, after the BMS is powered on, it controls the discharge contactor 23 and the charging contactor 22 to be attracted. At this time, if charging, the current flows through the charging interface-charging contactor 22-charging diode 28 to charge the battery; if discharging, the current flows through the discharge diode 29-discharge contactor 23-load interface to discharge. At this time, whether charging or discharging, the current can choose different circuits to conduct normally.

[0028] When the battery is about to reach the full charge point, the BMS controls the charging contactor 22 to disconnect. At this time, the charging circuit is disconnected and charging cannot be performed. The discharge contactor 23 is closed, and the discharge circuit is normally connected to ensure that the load uses electricity normally through the battery after the charging gun is pulled out; when the battery is about to reach the full discharge point, the BMS controls the discharge contactor 23 to disconnect. At this time, the discharge circuit is disconnected and discharge cannot be performed. At this time, if the charging gun is inserted, the charging contactor 22 is closed, and the charging gun continues to supply power to the load through the charging interface. At the same time, the charging gun charges the lithium battery through the charging contactor 22. Disconnect the switch contacts of the charging contactor 22, close the switch contacts of the discharge contactor 23, or disconnect the switch contacts of the discharge contactor 23, and close the switch contacts of the charging contactor 22 to form a seamless switching of charging and discharging, which can prevent the battery from being overcharged or over-discharged. By controlling the switch contacts of the charging contactor and the discharge contactor through the battery management system, charging and discharging automation can be achieved.

[0029] When the BMS detects that the battery system single cell voltage reaches the extreme protection value (such as 2.5V), it can automatically disconnect the self-locking contactor 24 to avoid low-voltage power consumption of the BMS when the battery power is too low, resulting in extreme power feeding of the battery.

[0030] When the user does not use the battery pack for a long time, the user can press the normally closed switch 25 to cut off the power of the BMS to prevent high voltage or BMS low voltage from continuing to consume power. The switch is disconnected in extreme protection, and the next time it is used, the normal system power-on process is followed.

[0031] As another embodiment, a fuse 21 is provided on the common branch connecting the power circuit and the battery management system (BMS) power supply circuit with the positive electrode of the battery, which can effectively prevent damage caused by circuit overload and short circuit, thereby ensuring the safety of the battery.

[0032] As another embodiment, a shunt 27 is provided on a common branch connecting the power circuit and the battery management system (BMS) power supply circuit to the negative electrode of the battery, so as to effectively manage the power, signal and data flow and realize the functional distribution and coordination of the circuit.

[0033] RV Example:

[0034] A motorhome of the present embodiment includes a battery for powering loads such as lighting in the motorhome, and also includes a battery power supply circuit for controlling the charging and discharging of the battery. The battery power supply circuit has been introduced clearly enough in the battery power supply circuit embodiment and will not be repeated here.

Claims

1. A battery power supply circuit, comprising a battery interface for connecting a battery, a charging interface and a load interface arranged in parallel, characterized in that: It also includes a charging branch and a discharging branch arranged in parallel, the charging branch includes a charging contactor and a charging diode connected in series, and the discharging branch includes a discharging contactor and a discharging diode connected in series; the conduction direction of the charging diode is the same as the direction of the charging current, and the conduction direction of the discharging diode is the same as the direction of the discharging current; after the charging branch and the discharging branch are connected in parallel, they are connected in series with the charging interface and the load interface arranged in parallel.

2. The battery power supply circuit according to claim 1, characterized in that: The switch contacts of the charging contactor and the switch contacts of the discharging contactor are controlled by a battery management system.

3. The battery power supply circuit according to claim 2, characterized in that: It includes a BMS power supply circuit for powering the battery management system. The BMS power supply circuit is connected in parallel at both ends of the battery interface. A self-locking contactor in the BMS power supply circuit is connected in parallel with a self-resetting switch and then in series with a normally closed switch.

4. The battery power supply circuit according to claim 3, characterized in that: The normally closed switch and the self-resetting switch are arranged on the power supply box.

5. A motorhome, comprising a battery power supply circuit, the battery power supply circuit comprising a battery, a charging interface and a load interface arranged in parallel, characterized in that: It also includes a charging branch and a discharging branch arranged in parallel, the charging branch includes a charging contactor and a charging diode connected in series, and the discharging branch includes a discharging contactor and a discharging diode connected in series; the conduction direction of the charging diode is the same as the direction of the charging current, and the conduction direction of the discharging diode is the same as the direction of the discharging current; after the charging branch and the discharging branch are connected in parallel, they are connected in series with the charging interface and the load interface arranged in parallel.

6. The recreational vehicle according to claim 5, characterized in that: The switch contacts of the charging contactor and the switch contacts of the discharging contactor are controlled by a battery management system.

7. The recreational vehicle according to claim 6, characterized in that: It includes a BMS power supply circuit for powering the battery management system. The BMS power supply circuit is connected in parallel at both ends of the battery. A self-locking contactor in the BMS power supply circuit is connected in parallel with a self-resetting switch and then in series with a normally closed switch.

8. The recreational vehicle according to claim 7, characterized in that: The normally closed switch and the self-resetting switch are arranged on the power supply box.

Images