阅读说明：本技术 一种充电电压切换装置、控制方法及汽车 (Charging voltage switching device, control method and automobile ) 是由 潘福中 占莉 郑松太 李慧明 赵跃新 吴旭峰 张震 于 2020-04-10 设计创作，主要内容包括：本发明涉及一种充电电压切换装置、控制方法及汽车,包括电压测量模块,用于测量充电设备的充电电压幅值；电压判断模块,用于根据充电设备的充电电压幅值判断充放电切换状态；充放电平台切换模块,用于根据充放电切换状态控制可控开关组的开断,即控制充放电电路在串联充电状态、并联充电状态和放电状态之间的切换,所述充放电电路包括第一电池组和第二电池组；切换状态监测模块,用于监测充放电电路的所在的充放电切换状态。采用把电池包电压分成两部分,通过切换控制器和开关组改变电池包两部分的逻辑关系,从而达到对电池包的升压和降压,在保障安全性的前提下,实现两种电压平台切换。(The invention relates to a charging voltage switching device, a control method and an automobile, comprising a voltage measuring module, a charging voltage switching module and a charging voltage switching module, wherein the voltage measuring module is used for measuring the amplitude of the charging voltage of charging equipment; the voltage judging module is used for judging a charging and discharging switching state according to the charging voltage amplitude of the charging equipment; the charging and discharging platform switching module is used for controlling the on-off of the controllable switch group according to the charging and discharging switching state, namely controlling the switching of a charging and discharging circuit among a series charging state, a parallel charging state and a discharging state, wherein the charging and discharging circuit comprises a first battery pack and a second battery pack; and the switching state monitoring module is used for monitoring the charging and discharging switching state of the charging and discharging circuit. The voltage of the battery pack is divided into two parts, and the logical relation between the two parts of the battery pack is changed through the switching controller and the switch group, so that the voltage of the battery pack is increased and reduced, and the switching between two voltage platforms is realized on the premise of ensuring the safety.)

1. A charging voltage switching apparatus, comprising:

a voltage measurement module (6) for measuring a charging voltage amplitude of the charging device (5);

the voltage judging module (7) is used for judging a charging and discharging switching state according to the charging voltage amplitude of the charging equipment (5);

the charging and discharging platform switching module (3) is used for controlling the on-off of the controllable switch group according to the charging and discharging switching state, namely controlling the switching of the charging and discharging circuit among a series charging state, a parallel charging state and a discharging state, wherein the charging and discharging circuit comprises a first battery pack (1) and a second battery pack (2);

the switching state monitoring module (8) is used for monitoring the charging and discharging switching state of the charging and discharging circuit;

first group battery (1) with second group battery (2) all with charge and discharge platform switches module (3) electricity and connects, charge and discharge platform switches module (3) and still is equipped with the input of charging and the output that discharges, the input of charging be used for with battery charging outfit (5) electricity is connected, the output that discharges is used for being connected with motor (4) electricity, the input of voltage measurement module (6) be used for with battery charging outfit (5) electricity is connected, the output of voltage measurement module (6) with the input electricity of voltage judgement module (7) is connected, the output of voltage judgement module (7) with charge and discharge platform switches module (3) electricity and connects, switch state monitoring module (8) with charge and discharge platform switches module (3) electricity and connects.

2. A charging voltage switching apparatus according to claim 1, wherein the charging and discharging platform switching module (3) comprises a switching controller and a switch group, the switch group comprises a first switch (31), a second switch (32), a third switch (33) and a fourth switch (34), one end of the first switch (31) is electrically connected with the positive pole of the first battery pack (1), the other end of the first switch (31) and the negative pole of the second battery pack (2) are used for being electrically connected with the two ends of the motor (4) respectively, the negative pole of the first battery pack (1) is electrically connected with the positive pole of the second battery pack (2), the first end of the charging device (5) is electrically connected with the positive pole of the first battery pack (1), the second end of the charging device (5) is electrically connected with the negative pole of the first battery pack (1) through the second switch (32), the second end of the charging device (5) is electrically connected with the negative electrode of the second battery pack (2) through a fourth switch (34), two ends of the third switch (33) are respectively electrically connected with the positive electrode of the first battery pack (1) and the negative electrode of the second battery pack (2), and the switching controller is respectively electrically connected with the first switch (31), the second switch (32), the third switch (33) and the fourth switch (34).

3. A charging voltage switching device according to claim 1, further comprising a malfunction alerting device (9), said malfunction alerting device (9) being electrically connected to said switching state monitoring module (8).

4. A method of controlling a charge voltage switching apparatus, the method being for controlling the charge voltage switching apparatus according to any one of claims 1 to 3, the method comprising:

acquiring charge and discharge information of a high-voltage system;

obtaining a charge-discharge switching state according to the charge-discharge information of the high-voltage system;

controlling to disconnect all the controllable switches in the controllable switch group;

and according to the charging and discharging switching state, executing the action of controlling the controllable switch group.

5. The control method of a charging voltage switching device according to claim 4, wherein the charging and discharging information of the high voltage system includes charging and discharging signals and charging voltage values, the charging and discharging signals include charging signals and discharging signals, the charging and discharging switching state includes a series charging state, a parallel charging state and a discharging state,

according to the high-voltage system charge-discharge information, obtaining the charge-discharge switching state comprises the following steps:

judging whether the charge and discharge signal is a discharge signal or not;

if so, the charge-discharge switching state is a discharge state;

if not, judging whether the charge-discharge signal is a charge signal or not;

if yes, judging whether the charging voltage value is larger than or equal to a preset voltage;

if the charging voltage value is greater than or equal to the preset voltage, the charging and discharging switching state is a series charging state;

and if the charging voltage value does not meet the condition that the charging voltage value is greater than or equal to the preset voltage, the charging and discharging switching state is a parallel charging state.

6. The method according to claim 5, wherein the performing the operation of controlling the controllable switch group according to the charge-discharge switching state comprises:

when the charging and discharging switching state is a series charging state, the fourth switch is controlled to be switched on and switched off, and the first switch, the second switch and the third switch are switched off;

when the charging and discharging switching state is a parallel charging state, the first switch and the fourth switch are sequentially controlled to be switched off, the second switch is switched on, and the third switch is switched on;

and when the charging and discharging switching state is a discharging state, controlling the first switch to be closed, and controlling the second switch, the third switch and the fourth switch to be opened.

7. The method for controlling a charging voltage switching device according to claim 4, wherein after the performing the operation of controlling the controllable switch group in response to the charging/discharging information of the high voltage system, the method further comprises:

acquiring electrical information of the first battery pack and the second battery pack;

obtaining a series-parallel connection state according to the electrical information of the first battery pack and the second battery pack, wherein the series-parallel connection state comprises a parallel connection state, a series connection state and an abnormal state;

judging whether the series-parallel connection state is a series connection state or not, and the charge-discharge switching state is a series connection charge or discharge state;

if not, controlling the controllable switch group to be completely disconnected and giving an alarm;

judging whether the series-parallel connection state is a parallel connection state and the charge-discharge switching state is a parallel connection charge state;

if not, controlling the controllable switch group to be completely disconnected and giving an alarm;

judging whether the series-parallel connection state is satisfied to be an abnormal state;

and if the series-parallel connection state is an abnormal state, controlling all the controllable switch groups to be disconnected and giving an alarm.

8. The control method according to claim 7, wherein the electrical information of the first battery pack and the second battery pack includes the first battery pack output current value, the second battery pack output current value, a voltage value between a negative electrode of the first battery pack and a positive electrode of the second battery pack, a voltage value across the first battery pack, and a voltage value across the second battery pack,

obtaining a series-parallel connection state according to the electrical information of the first battery pack and the second battery pack, wherein the series-parallel connection state comprises a parallel connection state, a series connection state and an abnormal state, and the series-parallel connection state comprises the following steps:

judging whether the output current value of the first battery pack is equal to the output current value of the second battery pack and the voltage value between the cathode of the first battery pack and the anode of the second battery pack is zero;

if so, the serial-parallel connection state is a serial connection state;

if not, judging whether the voltage values at the two ends of the first battery pack and the voltage values at the two ends of the second battery pack are equal and the output current value of the first battery pack is equal to the output current value of the second battery pack;

if so, the series-parallel connection state is a parallel connection state;

if not, the serial-parallel connection state is an abnormal state.

9. The method as claimed in claim 5, wherein the predetermined voltage is in a range of 450-550V.

10. A vehicle, characterized in that the vehicle comprises a charging voltage switching apparatus according to any one of claims 1 to 3.

Technical Field

The invention relates to the field of new energy automobiles, in particular to a charging voltage switching device, a control method and an automobile.

Background

The charging system provides energy supply for the operation of the electric automobile, is an important basic supporting system of the electric automobile, and is also an important link in the commercialization and industrialization processes of the electric automobile. With the rapid development of the electric automobile industry, the charging technology becomes one of the key factors restricting the industry development, and the intelligent and rapid charging mode becomes the development trend of the electric automobile charging technology.

At present, a voltage platform of a pure electric household automobile is 400VDC, the maximum power of a market charging pile is 150kW, and the full charging time is 80-100 minutes, the platform voltage is increased to 800VDC by the existing developed automobile type, so that the faster charging time is realized, the higher system efficiency is realized, and the time for charging to 80% of SOC is shortened to 25 minutes. However, no equipment capable of charging private cars with 800VDC platform exists in the existing Chinese market, no vehicle enterprises and governments have a plan of moving 800VDC charging piles in China for a while, the charging alliance Ionity in europe is just to start laying 800VDC charging equipment in europe, and the wide application of the charging alliance Ionity in europe still needs several years. Existing solutions in the market are DC/DC or Boost/buck, which are costly, heavy and large in size and require the use of a separate cooling system due to the large amount of heat generated.

Therefore, in order to solve the above problems, it is necessary to provide a charging voltage switching device, a control method, and an automobile capable of switching between two voltage platforms.

Disclosure of Invention

In order to solve the technical problems, the invention provides a charging voltage switching device, which divides the voltage of a battery pack into two parts, and changes the logic relation of the two parts of the battery pack through a switching controller and a switch group, so that the voltage boosting and the voltage reducing of the battery pack are achieved, the voltage platform switching of the battery pack at a low voltage level and a high voltage level is realized on the premise of ensuring the safety, and the requirement that the battery pack can be charged on the existing charging pile in the market is met.

The technical effects of the invention are realized as follows:

a charging voltage switching device comprises a voltage measuring module, a charging voltage measuring module and a charging voltage switching module, wherein the voltage measuring module is used for measuring the amplitude of a charging voltage of a charging device; the voltage judging module is used for judging a charging and discharging switching state according to the charging voltage amplitude of the charging equipment; the charging and discharging platform switching module is used for controlling the on-off of the controllable switch group according to the charging and discharging switching state, namely controlling the switching of a charging and discharging circuit among a series charging state, a parallel charging state and a discharging state, wherein the charging and discharging circuit comprises a first battery pack and a second battery pack; the switching state monitoring module is used for monitoring the charging and discharging switching state of the charging and discharging circuit; the first battery pack and the second battery pack are electrically connected with the charging and discharging platform switching module, the charging and discharging platform switching module is further provided with a charging input end and a discharging output end, the charging input end is used for being electrically connected with the charging equipment, the discharging output end is used for being electrically connected with the motor, the input end of the voltage measuring module is used for being electrically connected with the charging equipment, the output end of the voltage measuring module is electrically connected with the input end of the voltage judging module, the output end of the voltage judging module is electrically connected with the charging and discharging platform switching module, and the switching state monitoring module is electrically connected with the charging and discharging platform switching module.

Further, the charge and discharge platform switching module comprises a switching controller and a switch group, the switch group comprises a first switch, a second switch, a third switch and a fourth switch, one end of the first switch is electrically connected with the positive electrode of the first battery pack, the other end of the first switch and the negative electrode of the second battery pack are used for being electrically connected with two ends of a motor respectively, the negative electrode of the first battery pack is electrically connected with the positive electrode of the second battery pack, the first end of the charging device is electrically connected with the positive electrode of the first battery pack, the second end of the charging device is electrically connected with the negative electrode of the first battery pack through the second switch, the second end of the charging device is also electrically connected with the negative electrode of the second battery pack through the fourth switch, and two ends of the third switch are electrically connected with the positive electrode of the first battery pack and the negative electrode of the second battery pack respectively, the switching controller is electrically connected to the first switch, the second switch, the third switch, and the fourth switch, respectively.

Further, the switching state monitoring module further comprises a fault alarm device, and the fault alarm device is electrically connected with the switching state monitoring module.

In another aspect, the present application further provides a method for controlling a charging voltage switching device, where the method is used to control the charging voltage switching device, and the method includes:

acquiring charge and discharge information of a high-voltage system;

obtaining a charge-discharge switching state according to the charge-discharge information of the high-voltage system;

controlling to disconnect all the controllable switches in the controllable switch group;

and according to the charge-discharge switching state, executing control of the switch group to switch the charge-discharge circuit.

Further, the charge and discharge information of the high-voltage system comprises charge and discharge signals and a charge voltage value, the charge and discharge signals comprise a charge signal and a discharge signal, the charge and discharge switching state comprises a series charge state, a parallel charge state and a discharge state,

according to the high-voltage system charge-discharge information, obtaining the charge-discharge switching state comprises the following steps:

judging whether the charge and discharge signal is a discharge signal or not;

if so, the charge-discharge switching state is a discharge state;

if not, judging whether the charge-discharge signal is a charge signal or not;

if yes, judging whether the charging voltage value is larger than or equal to a preset voltage;

if the charging voltage value is greater than or equal to the preset voltage, the charging and discharging switching state is a series charging state;

and if the charging voltage value does not meet the condition that the charging voltage value is greater than or equal to the preset voltage, the charging and discharging switching state is a parallel charging state.

Further, the executing and controlling the controllable switch group according to the charging and discharging switching state includes:

when the charging and discharging switching state is a series charging state, the fourth switch is controlled to be switched on and switched off, and the first switch, the second switch and the third switch are switched off;

when the charging and discharging switching state is a parallel charging state, the first switch and the fourth switch are sequentially controlled to be switched off, the second switch is switched on, and the third switch is switched on;

and when the charging and discharging switching state is a discharging state, controlling the first switch to be closed, and controlling the second switch, the third switch and the fourth switch to be opened.

Further, after the operation of controlling the controllable switch group is executed in response to the charging and discharging information of the high-voltage system, the method further comprises the following steps:

acquiring electrical information of the first battery pack and the second battery pack;

obtaining a series-parallel connection state according to the electrical information of the first battery pack and the second battery pack, wherein the series-parallel connection state comprises a parallel connection state, a series connection state and an abnormal state;

judging whether the series-parallel connection state is a series connection state or not, and the charge-discharge switching state is a series connection charge or discharge state;

if not, controlling the controllable switch group to be completely disconnected and giving an alarm;

judging whether the series-parallel connection state is a parallel connection state and the charge-discharge switching state is a parallel connection charge state;

if not, controlling the controllable switch group to be completely disconnected and giving an alarm;

judging whether the series-parallel connection state is satisfied to be an abnormal state;

and if the series-parallel connection state is an abnormal state, controlling all the controllable switch groups to be disconnected and giving an alarm.

Further, the electrical information of the first battery pack and the second battery pack includes the output current value of the first battery pack, the output current value of the second battery pack, the voltage value between the cathode of the first battery pack and the anode of the second battery pack, the voltage value across the first battery pack and the voltage value across the second battery pack,

obtaining a series-parallel connection state according to the electrical information of the first battery pack and the second battery pack, wherein the series-parallel connection state comprises a parallel connection state, a series connection state and an abnormal state, and the series-parallel connection state comprises the following steps:

judging whether the output current value of the first battery pack is equal to the output current value of the second battery pack and the voltage value between the cathode of the first battery pack and the anode of the second battery pack is zero;

if so, the serial-parallel connection state is a serial connection state;

if not, judging whether the voltage values at the two ends of the first battery pack and the voltage values at the two ends of the second battery pack are equal and the output current value of the first battery pack is equal to the output current value of the second battery pack;

if so, the series-parallel connection state is a parallel connection state;

if not, the serial-parallel connection state is an abnormal state.

Further, the range of the preset voltage is 450-550V.

On the other hand, the application also provides an automobile, and the automobile comprises the charging voltage switching device.

As described above, the present invention has the following advantageous effects:

1) the size is small, and the occupied space is small. The switching controller switches through the control switch group and is integrated in a high-voltage control box in the battery pack, so that the space of other parts of the whole vehicle is not occupied, and the structure is simple.

2) The weight is light. Because the scheme only adds the circuit control module, the circuit control module has light weight and a small number of applied electric elements.

3) The heat dissipation is less. The internal resistance of the charging voltage switching unit is small, the power consumption is low, and the generated heat is low.

4) The cost is low. The charging switching unit is not an independent product, independent consideration of structures such as protection and fixation of the installation environment is not needed, the realization form is simple, and the cost is greatly reduced compared with the existing scheme.

5) The safety is high. Through modes such as switching state that switches state monitoring module monitoring charge-discharge circuit, avoid the circuit to lead to appearing all kinds of short circuit trouble owing to controllable switch misoperation in the switching process, and then cause the accident, improved the security of this device.

Drawings

In order to more clearly illustrate the technical solution of the present invention, the drawings used in the description of the embodiment or the prior art will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the invention, and that for a person skilled in the art it is also possible to derive other drawings from these drawings without inventive effort.

FIG. 1 is a schematic block diagram of a control circuit of the present application;

FIG. 2 is a schematic diagram of a charging and discharging circuit according to the present application;

FIG. 3 is a flow chart of a control method in an embodiment of the present application;

fig. 4 is a flowchart of steps included in S2 of the control method in the embodiment of the present application.

Fig. 5 is a flowchart illustrating steps included in the control method S4 according to an embodiment of the present invention.

Fig. 6 is a flowchart illustrating steps included in the control method S5 according to an embodiment of the present invention.

Fig. 7 is a flowchart illustrating steps included in the control method S52 according to an embodiment of the present invention.

Fig. 8 is a schematic diagram of a charging and discharging circuit according to another embodiment of the present application.

Wherein the reference numerals correspond to:

1-a first battery pack, 2-a second battery pack, 3-a charging and discharging platform switching module, 31-a first switch, 32-a second switch, 33-a third switch, 34-a fourth switch, 35-a fifth switch, 36-a sixth switch, 37-a seventh switch, 4-a motor, 5-a charging device, 6-a voltage measuring module, 7-a voltage judging module, 8-a switching state detecting module and 9-a fault alarm device.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.