CN112350445A

CN112350445A - Receiving terminal of wireless charging system

Info

Publication number: CN112350445A
Application number: CN202011021306.7A
Authority: CN
Inventors: 葛俊杰; 王哲; 陆钧; 贺凡波; 马俊超
Original assignee: Beijing Invispower Co Ltd
Current assignee: Beijing Invispower Co Ltd
Priority date: 2020-09-25
Filing date: 2020-09-25
Publication date: 2021-02-09

Abstract

The invention discloses a receiving end of a wireless charging system, which is divided into a main path and a branch path, wherein the main path comprises: the main circuit comprises a power receiving coil, a main circuit working circuit and a main circuit load, wherein the main circuit working circuit is provided with compensation inductance; the branch circuit includes: the branch receiving coil is coupled with the compensation inductor. According to the receiving end of the wireless charging system, the branch receiving coil in the branch is coupled with the compensation inductor of the main circuit, electricity is taken from the main circuit and electric energy is output through the branch output port, the electric energy output by the branch output port can replace an auxiliary power supply to be used, and the consumption of the electric energy of the auxiliary power supply is reduced.

Description

Receiving terminal of wireless charging system

Technical Field

The invention relates to the field of wireless charging, in particular to a receiving end of a wireless charging system.

Background

The wireless charging is a non-contact energy transmission mode, can realize the safe and efficient utilization of energy, particularly, the wireless charging adopted by the electric automobile capable of automatically driving and automatically parking can effectively support the whole unmanned operation of the automobile, and is an important direction for the development of new energy automobiles.

In the wireless charging starting and working processes, the charged device also needs to realize the processes of starting and controlling the wireless charging function through an auxiliary power supply. For example, before the wireless charging of an automobile is started, a power transmitting coil and a power receiving coil need to be positioned and aligned, and after the pairing is successful, the wireless charging process can be started; in the charging process, the transmitting end and the receiving end need to keep communication, and working parameters, such as charging power and the like, in the charging process are adjusted at any time.

During wireless charging, the auxiliary power supply is still required to provide low-voltage electric energy to complete work, however, the battery of the electric automobile can be charged through the wireless charging, the auxiliary power supply (battery cell) cannot be charged, even the electric energy of the auxiliary power supply is required to be used for maintaining the wireless charging, and therefore the electric energy consumption of the auxiliary power supply is increased. Meanwhile, before the wireless charging is started or in the wireless charging process, if the auxiliary power supply fails, the wireless charging function is blocked, and even danger may occur.

Disclosure of Invention

The invention provides a receiving end of a wireless charging system, which can obtain electricity and output the electricity in an isolated way from a main circuit of the receiving end.

The receiving end of the wireless charging system is divided into a main path and a branch path, wherein the main path comprises: the main circuit comprises a power receiving coil, a main circuit working circuit and a main circuit load, wherein the main circuit working circuit is provided with compensation inductance; the branch circuit includes: the branch receiving coil is coupled with the compensation inductor.

Preferably, the main circuit operating circuit includes: a main circuit compensation circuit and a main circuit rectification circuit; the branch circuit operating circuit includes: branch circuit compensating circuit and branch circuit rectifier circuit.

Preferably, the branch output port supplies low-voltage power to the main path.

Preferably, the device also comprises an auxiliary power supply; and the auxiliary power supply and the branch output port selectively supply low-voltage power to the main circuit.

Preferably, the auxiliary power supply has a larger output voltage than the branch output port, and supplies power to the main circuit operating circuit at a low voltage.

Preferably, the branch output port is connected to a monitor for monitoring the operating state of the main operating circuit.

Preferably, the branch output port is connected to a protection circuit, and at least used for supplying power to the protection circuit.

Preferably, the protection circuit includes: the circuit comprises a sampling circuit, a comparison circuit and a control switch; the sampling circuit is used for acquiring an electric signal of a main circuit; the comparison circuit adjusts the on-off state of the control switch according to the electric signal; wherein the sampling circuit is connected with the branch output port (6); or, the sampling circuit is connected with the main circuit; or, the sampling circuit is connected to the main path and the branch output port at the same time.

Preferably, the main circuit rectifying circuit has a switching tube, and the control switch is connected to the switching tube.

According to the receiving end of the wireless charging system, the branch receiving coil in the branch is coupled with the compensation inductor of the main circuit, electricity is taken from the main circuit and electric energy is output through the branch output port, the electric energy output by the branch output port can replace an auxiliary power supply to be used, and the consumption of the electric energy of the auxiliary power supply is reduced.

According to the branch output port, different functional circuits are connected, multiple functions can be achieved, for example, low-voltage power supply is carried out on a main circuit, in the wireless charging process, main energy consumption of an auxiliary power supply is located, low-voltage electric energy is output through the branch output port, redundant power supply can be formed in the auxiliary power supply, when the auxiliary power supply fails, the auxiliary power supply is replaced to work, and the problem in the wireless charging process is avoided. In addition, the branch output port can be used for connecting a monitor to monitor the main circuit working circuit; and the protection circuit is connected to protect the working safety of the main circuit working circuit.

Drawings

Fig. 1 is a schematic view of the overall structure of a receiving end of a wireless charging system according to the present invention;

fig. 2 is a schematic view of a receiving end topology of the wireless charging system of the present invention;

fig. 3 is a schematic diagram of a receiving end connection protection circuit according to a first embodiment of the present invention;

fig. 4 is a schematic diagram of a second embodiment of a receiving end connection protection circuit of the wireless charging system according to the present invention;

fig. 5 is a schematic diagram of a third embodiment of a receiving end connection protection circuit of the wireless charging system according to the present invention;

fig. 6 is a schematic diagram of a fourth embodiment of a receiving end connection protection circuit of the wireless charging system according to the present invention;

fig. 7 is a schematic diagram of the receiving end branch output port and the auxiliary power supply of the wireless charging system of the present invention simultaneously connected to the main circuit operating circuit.

Reference numerals:

a power receiving coil 1; a main circuit operating circuit 2; main-path load 3; a branch receiving coil 4; a branch circuit operating circuit 5; a branch output port 6; a protection circuit 7; an auxiliary power supply 9; a rectifying circuit 22; a branch compensation circuit 51; a branch rectifying circuit 52; a conversion circuit 53; a sampling circuit 71; a comparison circuit 72; a control switch 73; an upper pipe 81; a lower tube 82; a compensation inductance 211; a first capacitor 212; a second capacitor 213.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative only and should not be construed as limiting the invention.

The invention discloses a receiving end of a wireless charging system, which is divided into a main circuit and a branch circuit. The main circuit is used for being matched with the transmitting terminal to realize a wireless power transmission path, and mainly charges a load 3 of the main circuit, and the load of the main circuit is generally a battery of equipment. The branch circuit is a circuit for implementing other functions related to wireless charging, such as monitoring and low-voltage power supply of the circuit. The main path and the branch path will be specifically explained below.

Referring to fig. 1 and 2, the main road includes: a power receiving coil 1, a main circuit operating circuit 2 and a main circuit load 3. The power receiving coil 1 can be matched with a power transmitting coil of a transmitting end to realize wireless transmission of electric energy. The main circuit working circuit 2 is connected between the power receiving coil 1 and the main circuit load 3, and processes the electric energy received by the power receiving coil 1 to ensure that the main circuit working circuit can supply power and charge the main circuit load 3. The main circuit operating circuit 2 has a compensation inductance 211, i.e. the main circuit operating circuit 2 includes a main circuit compensation circuit therein, and the compensation inductance 211 may be a component of the compensation circuit. The compensation circuit can be in the form of "LCC", "LCL", etc., and can be set according to actual conditions. As shown in fig. 2, in a preferred embodiment of the present application, a compensation circuit in the form of an "LCC" is used, and the compensation circuit has a first capacitor 212, a second capacitor 213 and a compensation inductor 211. Of course, the drawings are only for the purpose of illustration to facilitate understanding of the present application and are not intended to limit the scope of the present application. In addition, the main circuit operating circuit 2 includes a main circuit rectifying circuit 22.

The branch circuit includes: a branch receiving coil 4, a branch working circuit 5 and a branch output port 6. The branch receiving coil 4 is coupled to the compensation inductance 211 of the main path. Therefore, when the power receiving coil 1 and the power transmitting coil at the transmitting end work in a matching manner, the branch receiving coil 4 and the compensation inductor 211 can realize the transmission of electric energy, and after the electric energy is processed by the branch working circuit 5, the electric energy is output from the branch output port 6. The branch output port 6 is connected to different subsequent working parts, and can realize various functions. For example, low-voltage power supply (low-voltage control, work and the like required by wireless charging) can be performed on the main circuit; a monitor can also be connected to monitor the working state of the main circuit working circuit 2; a protection circuit 7 is also connected to realize protection of the main path and the like. The branch circuit operating circuit 5 further includes: a branch compensation circuit 51 and a branch rectification circuit 52. It should be noted that the above-mentioned "performing low-voltage power supply on the main circuit" and the power supply in "wireless charging" are different concepts, and here, the low-voltage power supply is auxiliary power supply required for the main circuit to realize the wireless charging function, and is not wireless charging itself. For example, a controller, a communicator, a signal collector, and the like, which are required in the wireless charging process, may be implemented by supplying power to the branch output port 6 through the device that needs low-voltage power supply, for which, please refer to the following description.

The branch output port 6 is connected with a monitor, the electric energy of the main circuit is transmitted to the branch through the compensation inductor 211, the transmission of the electric signal from the main circuit to the branch is realized, and the monitor can be used for measuring and controlling the main circuit.

The protection circuit 7 for low-voltage power supply will be described below.

The low-voltage power supply is described first, and the low-voltage power supply may be power supply to a main circuit to realize control of wireless charging and the like, or power supply to other power consumption units of a vehicle, and may be specifically set according to actual requirements, such as power supply to a display lamp of a charging state, an electronic door lock of the vehicle, and the like.

We will explain the example of low voltage supply to the main path. In the prior art, the receiving end of the wireless charging system can supply power at low voltage through an auxiliary power supply 9, such as a storage battery of a vehicle, so as to realize the function of wireless charging. It should be noted that although the wireless charging process is a high-power transmission process, before the wireless charging process is started, a plurality of steps such as communication, alignment, pairing and the like of a receiving end and a transmitting end may be included, and these steps need to be implemented by low-voltage power supply, or steps such as control and adjustment in the charging process may also be implemented by low-voltage power supply. Therefore, in the process of carrying out high-power wireless charging, procedures such as auxiliary control and the like are also required to be carried out by low-voltage power supply.

When the branch output port 6 of the application supplies power to the main circuit at low voltage, a redundant power supply mode can be understood, and the electric automobile is charged as an example and supplies power together with an automobile storage battery. Therefore, when the automobile storage battery fails or cannot work due to other reasons, the branch output port 6 can take over the storage battery to continue the current work. It should be noted that, in the embodiment of wirelessly charging an electric vehicle, the "battery cell" is mentioned herein, and for convenience of understanding, the "battery cell" may be a corresponding battery in other devices applying wireless charging.

In some embodiments, the branch output port 6 and the battery (auxiliary power supply 9) are connected to the main circuit working circuit 2 at the same time, and the two are selected to supply low-voltage power to the main circuit. In different embodiments, the priority levels may be set, for example, it may be specified that when both are connected to the main circuit at the same time, the auxiliary power supply 9 is preferentially used for supplying power, and when the auxiliary power supply 9 cannot supply power, the branch output port 6 is used for supplying power, but this may require a control unit or other components to implement selection, for example, the main circuit may be supplied with low voltage alternatively from the branch output port 6 and the auxiliary power supply 9 by an intelligent switch or other determination steps.

The convenient and fast way is that the higher voltage of the two is used to complete the corresponding low-voltage power supply. That is, even if the battery has not failed, the branch output port 6 can still replace the battery. In this way, it may be the case that the branch output port 6 and the auxiliary power supply 9 are alternately supplied with a change in voltage. It should be noted that in other situations where low voltage power is required, the bypass output port 6 may be powered alternatively to the auxiliary power supply 9.

Referring to fig. 7, which shows a schematic diagram of the branch output port 6 and the auxiliary power supply 9 being provided at the same time, the output port of the auxiliary power supply 9 may be shared with the branch output port 6. The branch compensation circuit 51 in the branch working circuit 5 may have the same or similar structure as the main circuit compensation circuit, and of course, the specific mechanisms of the two can be adjusted as required by those skilled in the art, and both functions of the compensation circuit can be implemented. The power supply to the main circuit operating circuit 2 is shown in fig. 7 as a schematic diagram only, with the branch output port 6 and the auxiliary power supply 9 both connected to the main circuit operating circuit 2 and alternatively powered in accordance with the several ways described above. The main circuit operating circuit 2 is shown here, on one hand, for convenience of understanding of the drawings, and on the other hand, other devices which need to use electricity may be included in the main circuit operating circuit 2, or other devices which use electricity may be communicated with the main circuit operating circuit 2, that is, components including a controller, a communicator, and the like may be regarded as components of the main circuit operating circuit 2. Of course, neither the branch output port 6 nor the auxiliary power supply 9 is low voltage powered solely for the main circuit 2, but they may also power other units that require power supply.

It should be noted that fig. 7 is only used as an example, wherein the branch compensation circuit 51 only shows a capacitor, and in practical applications, the branch compensation circuit 51 should be set according to requirements, for example, the setting of the main circuit compensation circuit can be referred to, including but not limited to "LLC" and "LCL" type compensation circuits. In some embodiments, a conversion circuit 53, typically a DC-DC converter, is further connected behind the branch rectifying circuit 52 to ensure that the branch output port 6 can effectively output a fixed voltage to meet the requirements of subsequent electric devices.

Although both can provide low voltage power supply, the premise of the operation of the branch output port 6 requires that the main circuit operating circuit 2 can first provide power for the branch output port, that is, the compensation inductor 211 and the branch receiving coil 4 need to be coupled, and the power transfer is realized. Therefore, the effect of mutual influence is achieved between the branch circuit and the main circuit. If there is no current in the main circuit operating circuit 2 (e.g., the power receiving coil 1 loses its coupling with the power transmitting coil), the branch output port 6 is also unable to provide low voltage power. It should be noted that, whether wireless charging is being performed or not does not directly determine whether the branch output port 6 can output low-voltage current, for example, the main circuit load 3 completes charging and is disconnected from the main circuit working circuit 2 by a controller or the like, but current may exist in the main circuit working circuit 2; alternatively, it can be understood that when the power receiving coil 1 and the power transmitting coil are coupled, no matter whether wireless charging is performed, there may be current in the main circuit operating circuit 2, so that the branch output port 6 may perform low-voltage power supply.

In addition to the above-mentioned low-voltage supply for the main circuit operating circuit 2, the branch output port 6 is connected to a monitor for monitoring the operating state of the main circuit. The dc voltage output by the rectifying circuit 22 can reflect the current in the compensation inductor 211, so when the branch output port 6 is connected to the monitor, it can be regarded as a monitoring system isolated from the main circuit, and can be used for measurement and control of the main circuit.

The following describes a case where the branch output port 6 is connected to the protection circuit 7.

The protection circuit 7 includes: the sampling circuit 71 is connected with the branch output port 6, and the sampling circuit 71 acquires the electrical signal of the branch or takes electricity from the branch output port 6; the comparator circuit 72 adjusts the on/off state of the control switch 73 based on the electric signal.

The sampling circuit 71 is configured to collect an electrical signal on the main path, and the collection position may be set according to an actual situation, for example, data collection may be performed at positions of the main path compensation circuit, the rectification circuit 22, the main path load 3, and the like, or only one or more positions may be collected.

The sampling may also be performed in a variety of ways, such as by data acquisition directly from the acquisition location by the acquisition device. Data acquisition can also be indirectly realized through the branch output port 6, however, this way may cause a limitation on the acquisition position, mainly the data when the branch receiving coil 4 acquires electric energy from the compensation inductor 211, and if the data of the main road load 3 is to be acquired, the data accuracy of this way may be lower than the data acquired at the main road load 3 through the acquisition device.

The branch output port 6 may be connected to the protection circuit 7 to supply power and data. I.e. the branch output port 6 is able to supply at least the protection circuit 7 to guarantee the operation of the sampling circuit 71, the comparison circuit 72 and the control switch 73. Besides, the branch output port 6 can also provide the sampling circuit 71 with an electrical signal, that is, the auxiliary sampling circuit 71 collects data of a corresponding position.

Synthesize in this application, protection circuit 7 get the electricity and sample and can simultaneous working, no matter be branch road output port 6 or main road, can both provide the electric energy and can provide the signal of telecommunication again. Of course, the collected electrical signals may vary according to the working principle of the protection circuit 7. For example, in addition to acquiring the electric signal of the main path, other parts of the electric signal may be acquired as the comparison data.

It is noted that the power of the protection circuit 7 may also be supplied by the auxiliary power supply 9, and that the branch output port 6 and the auxiliary power supply 9 alternatively supply power to the protection circuit 7, similar to supplying low voltage power to the main circuit.

The control switch 73 is generally connected to the switching tube of the main circuit rectifying circuit 22, for example, the two are connected in parallel, and the control switch 73 can prevent the main circuit working circuit 2 or the main circuit load 3 from being damaged by the problems of over-high voltage and the like by means of short-circuiting the switching tube. In some embodiments, the control switch may be connected to each switch tube. It should be understood that one purpose of the control switch 73 is to short-circuit the switch tube to avoid the high voltage from damaging the main circuit, and therefore, the position of the control switch 73 is not limited to one. For example, as shown in fig. 3, the control switch 73 is provided on all upper tubes 81 or all lower tubes 82. Alternatively, all the switch tubes may be short-circuited by connecting a control switch 73 to the main line as shown in fig. 4. For example, as shown in fig. 5, the control switch 73 is disposed between the main circuit rectifier circuits 22, and when the control switch 73 is closed to be connected, the main circuit rectifier circuit 22 and the subsequent main circuit load 3 can be in a short-circuit state, thereby playing a role of protection. Depending on the application scenario, the choice of the protection switch 73 can be adjusted, for example, it is most common to use an electronically controlled switch directly, and in some special cases, as shown in fig. 6, it uses a switch formed by combining MOS transistors, mainly considering the application in automobiles for example, and the common switch may not meet the requirements of vehicle manufacturing (not meeting the vehicle specifications). It can be seen that the specific structure of the protection switch 73 needs to be selected according to actual requirements, and it is sufficient that it can implement the corresponding protection function.

The present application only illustrates several optional mounting positions of the control switch 73, and in application, the appropriate position may be selected according to different characteristics of the circuit.

The control switch 73 of the present application is intended to protect the circuit, its specific mounting location, and its operating mode by closing when the voltage is too high (or other electrical parameters are not satisfactory) as desired.

Preferably, the comparator 72 is a hysteresis comparator. When the voltage acquired by the sampling circuit 71 is higher than a first predetermined value, the protection function of the protection circuit 7 is turned on (for example, the switch tube is shorted by the control switch 73 as described above), and when the voltage acquired by the sampling circuit 71 is smaller than a second predetermined value, the protection function is stopped. The first predetermined value and the second predetermined value are typically a threshold value. Because the hysteresis comparison circuit is adopted, the start protection function and the stop protection function can be ensured to have two different voltage values, namely the first preset value and the second preset value are different, the first preset value is larger than the second preset value generally, for example, the first preset value is set to be 100V, in the process that the voltage is gradually increased to 100V, the protection is not started, and the protection is triggered only when the voltage is larger than 100V. When the protection function is triggered, if the voltage is reduced and still higher than the second predetermined value (for example, the second predetermined value is 80V), the protection state is still maintained, and the protection is stopped only if the voltage is reduced to be less than 80V.

To sum up, in the receiving terminal of this application wireless charging system, the branch road gets the electricity from the compensation inductance 211 of main road through branch road receiving coil 4, is exported appointed functional module by branch road output port 6, realizes different functions. Compared with the method of directly taking electricity from the circuit of the main circuit, the method of taking electricity through the compensation inductor 211 is safer and more reliable.

The construction, features and functions of the present invention are described in detail in the embodiments illustrated in the drawings, which are only preferred embodiments of the present invention, but the present invention is not limited by the drawings, and all equivalent embodiments modified or changed according to the idea of the present invention should fall within the protection scope of the present invention without departing from the spirit of the present invention covered by the description and the drawings.

Claims

1. A receiving end of a wireless charging system is characterized in that,

is divided into a main path and a branch path, wherein,

the main path includes:

a power receiving coil (1), a main circuit operating circuit (2) and a main circuit load (3), the main circuit operating circuit (2) having a compensation inductance (211);

the branch circuit includes:

the circuit comprises a branch receiving coil (4), a branch working circuit (5) and a branch output port (6), wherein the branch receiving coil (4) is coupled with the compensation inductor (211).

2. The receiving end of the wireless charging system according to claim 1,

the main circuit operating circuit (2) includes: a main circuit compensation circuit and a main circuit rectification circuit (22);

the branch operating circuit (5) includes: a branch compensation circuit (51) and a branch rectification circuit (52).

3. The receiving end of the wireless charging system according to claim 1,

and the branch output port (6) supplies low-voltage power to the main circuit.

4. The receiving end of the wireless charging system according to claim 1,

also comprises an auxiliary power supply (9);

and the auxiliary power supply (9) and the branch output port (6) alternatively supply low-voltage power to the main circuit.

5. The receiving end of the wireless charging system according to claim 4,

compared with the branch output port (6), the auxiliary power supply (9) has a larger output voltage and supplies power to the main circuit working circuit (2) at a low voltage.

6. The receiving end of the wireless charging system according to claim 1,

and the branch output port (6) is connected with a monitor for monitoring the working state of the main working circuit (2).

7. The receiving end of the wireless charging system according to claim 1,

the branch output port (6) is connected with a protection circuit (7) and at least used for supplying power to the protection circuit (7).

8. The receiving end of the wireless charging system according to claim 7,

the protection circuit (7) includes: a sampling circuit (71), a comparison circuit (72) and a control switch (73);

the sampling circuit (71) is used for acquiring an electric signal of a main path;

the comparison circuit (72) adjusts the on-off state of the control switch (73) according to the electric signal; wherein the content of the first and second substances,

the sampling circuit (71) is connected with the branch output port (6); alternatively, the first and second electrodes may be,

the sampling circuit (71) is connected to the main path; alternatively, the first and second electrodes may be,

the sampling circuit (71) connects the main path and the branch output port (6) simultaneously.

9. The receiving end of the wireless charging system according to claim 8,

the main circuit working circuit (2) comprises a main circuit rectifying circuit (22);

the main circuit rectifying circuit (22) is provided with a switching tube, and the control switch (73) is connected with the switching tube.