CN111301111B - Vehicle heating wire preheating circuit, control method and control device - Google Patents

Abstract

The invention provides a vehicle heating wire preheating circuit, a control method and a control device, wherein the vehicle heating wire preheating circuit comprises the following components: the first heating wire, the second heating wire, the third heating wire, the first switch, the second switch and the third switch; the first end of the first heating wire and the first end of the second heating wire are connected with the first end of the first switch; the first end of the third heating wire is connected with the second end of the first switch, and the second end of the third heating wire is connected with the first end of the second switch; the second end of the second switch is connected with the second end of the second heating wire and the first end of the third switch respectively; the second end of the first heating wire is connected with the second end of the third switch. The vehicle heating wire preheating circuit can reduce the starting impact current of the vehicle heating wire preheating circuit to one third of the original starting impact current without adding additional voltage dividing components, thereby not only effectively controlling the cost of parts, but also protecting the vehicle heating wire preheating circuit from being damaged by the impact current.

Description

A vehicle electric heating wire preheating circuit and control method and control device

Technical field

The present invention relates to the field of vehicle control technology, and more specifically, to a vehicle electric heating wire preheating circuit, a control method and a control device.

Background technique

Since the heat generated by parts of electric vehicles is much lower than that of traditional fuel vehicles, electric heating wires are needed for vehicle air-conditioning heaters to ensure heat supply needs.

However, since the resistance of the heating wire is very low when it is cold, there will be a large inrush current when starting, which can easily cause damage to various parts in the circuit.

Contents of the invention

In view of this, in order to solve the above problems, the present invention provides a vehicle electric heating wire preheating circuit, a control method and a control device. The technical solution is as follows:

A vehicle electric heating wire preheating circuit, the vehicle electric heating wire preheating circuit includes: a first electric heating wire, a second electric heating wire, a third electric heating wire, a first switch, a second switch and a third switch;

The first end of the first heating wire and the first end of the second heating wire are both connected to the first end of the first switch;

The first end of the third electric heating wire is connected to the second end of the first switch, and the connection node between the first end of the third electric heating wire and the second end of the first switch serves as the vehicle electric heater. The input terminal of the wire preheating circuit;

The second end of the third heating wire is connected to the first end of the second switch; the second end of the second switch is connected to the second end of the second heating wire and the third end of the third switch respectively. First end connection;

The second end of the first electric heating wire is connected to the second end of the third switch, and the connection node between the second end of the first electric heating wire and the second end of the third switch serves as the vehicle electric heater. The output terminal of the wire preheating circuit.

Preferably, the vehicle electric heating wire preheating circuit includes a first gear state, a second gear state, a third gear state, a fourth gear state and a fifth gear state;

Wherein, when the vehicle electric heating wire preheating circuit is in the first gear state, the first switch and the third switch are in a cut-off state, and the second switch is in a conductive state;

When the vehicle electric heating wire preheating circuit is in the second gear state, the first switch is in the on state, and the second switch and the third switch are in the off state;

When the vehicle heating wire preheating circuit is in the third gear state, the first switch and the third switch are in a conductive state, and the second switch is in a cut-off state;

When the vehicle electric heating wire preheating circuit is in the fourth gear state, the first switch, the second switch and the third switch are all in a conductive state;

When the vehicle electric heating wire preheating circuit is in the fifth gear state, the first switch, the second switch and the third switch are all in a cut-off state.

The present invention also provides a control method, which is applied to the vehicle electric heating wire preheating circuit described in any one of the above, and the control method includes:

Determine whether the vehicle electric heating wire preheating circuit is in working condition;

If so, control the second switch to be in the on state, and the first switch and the third switch to be in the off state;

Determine whether the temperature of the vehicle electric heating wire preheating circuit reaches the preset temperature;

If so, receive the gear status command;

Wherein, the gear status instruction is used to control the switch status of the first switch, the second switch and the third switch.

Preferably, the control method further includes:

If the vehicle electric heating wire preheating circuit is not in the working state, return to the step of determining whether the vehicle electric heating wire preheating circuit is in the working state.

Preferably, the control method further includes:

If the temperature of the vehicle electric heating wire preheating circuit does not reach the preset temperature, then return to the step of determining whether the temperature of the vehicle electric heating wire preheating circuit reaches the preset temperature.

The invention also provides a control device, which includes:

The first judgment module is used to judge whether the vehicle electric heating wire preheating circuit is in working condition;

A first control module, used to control the second switch to be in an on state, and the first switch and the third switch to be in an off state when the vehicle electric heating wire preheating circuit is in a working state;

The second judgment module is used to judge whether the temperature of the vehicle electric heating wire preheating circuit reaches the preset temperature;

The second control module is used to receive a gear status instruction when the temperature of the vehicle electric heating wire preheating circuit reaches a preset temperature; wherein the gear status instruction is used to control the first switch, the third switch, and the first switch. The switching status of the second switch and the third switch.

Preferably, the control device further includes: a third control module;

The third control module is used to trigger the first judgment module when the vehicle electric heating wire preheating circuit is not in a working state.

Preferably, the control device further includes: a fourth control module;

The fourth control module is used to trigger the second judgment module when the temperature of the vehicle electric heating wire preheating circuit does not reach a preset temperature.

Compared with the existing technology, the beneficial effects achieved by the present invention are:

This vehicle electric heating wire preheating circuit reduces the starting impulse current of the vehicle electric heating wire preheating circuit to one-third of the original without adding additional voltage dividing components, which not only effectively controls the cost of parts, but also protects The vehicle heating wire preheating circuit avoids damage from surge current.

Description of the drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are only These are embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the provided drawings without exerting creative efforts.

Figure 1 is a schematic structural diagram of a vehicle heating wire preheating circuit in the prior art;

Figure 2 is a schematic structural diagram of a vehicle electric heating wire preheating circuit provided by an embodiment of the present invention;

Figure 3 is a schematic flow chart of a control method provided by an embodiment of the present invention;

Figure 4 is a schematic flowchart of a control device provided by an embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

Referring to Figure 1, Figure 1 is a schematic structural diagram of a vehicle electric heating wire preheating circuit in the prior art. There are three electric heating wires, each of which is connected in series with a switch and then connected in parallel. The vehicle electric heating wire preheating circuit is based on the heating demand. , controlling the closing of the three switches. The PWM method is used during preheating. At the moment of startup, the electric heating wire is slowly preheated by frequently opening and closing the switch, and then the switch is closed to start working.

However, the vehicle heating wire preheating circuit has limited suppression of the impulse current. The impulse current is still two to three times the normal operating current, and frequent switching has a large and frequent impact on the entire vehicle heating wire preheating circuit, affecting the life of the device. .

The vehicle electric heating wire preheating circuit provided by the present invention reduces the starting impulse current of the vehicle electric heating wire preheating circuit to one-third of the original without adding additional voltage dividing components, which effectively controls the cost of parts. , and can protect the vehicle's electric heating wire preheating circuit from being damaged by impact current.

In order to make the above objects, features and advantages of the present invention more obvious and understandable, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

Referring to Figure 2, Figure 2 is a schematic structural diagram of a vehicle heating wire preheating circuit provided by an embodiment of the present invention; the vehicle heating wire preheating circuit includes: a first heating wire R1, a second heating wire R2, and a third heating wire R3. , the first switch S1, the second switch S2 and the third switch S3;

The first end of the first heating wire R1 and the first end of the second heating wire R2 are both connected to the first end of the first switch S1;

The first end of the third heating wire R3 is connected to the second end of the first switch S1, and the connection node between the first end of the third heating wire R3 and the second end of the first switch S1 serves as The input end of the vehicle electric heating wire preheating circuit;

The second end of the third electric heating wire R3 is connected to the first end of the second switch 2; the second end of the second switch S2 is connected to the second end of the second electric heating wire R2 and the second end of the second electric heating wire R2. The first terminal of the third switch S3 is connected;

The second end of the first heating wire R1 is connected to the second end of the third switch S3, and the connection node between the second end of the first heating wire R1 and the second end of the third switch S3 serves as The output end of the vehicle electric heating wire preheating circuit.

Specifically, the vehicle electric heating wire preheating circuit includes a first gear state, a second gear state, a third gear state, a fourth gear state and a fifth gear state;

Wherein, when the vehicle electric heating wire preheating circuit is in the first gear state, the first switch S1 and the third switch S3 are in the off state, and the second switch S2 is in the on state;

When the vehicle heating wire preheating circuit is in the second gear state, the first switch S1 is in the on state, and the second switch S2 and the third switch S3 are in the off state;

When the vehicle heating wire preheating circuit is in the third gear state, the first switch S1 and the third switch S3 are in the on state, and the second switch S2 is in the off state;

When the vehicle electric heating wire preheating circuit is in the fourth gear state, the first switch S1, the second switch S2 and the third switch S3 are all in a conductive state;

When the vehicle electric heating wire preheating circuit is in the fifth gear state, the first switch S1, the second switch S2 and the third switch S3 are all in a cut-off state.

Wherein, the first gear state is the preheating state of the vehicle electric heating wire preheating circuit, when the first switch S1 and the third switch S3 are in the off state, and the second switch S2 is in the on state. , the first electric heating wire R1, the second electric heating wire R2 and the third electric heating wire R3 are connected in series, which increases the loop resistance of the vehicle electric heating wire preheating circuit and reduces the starting impulse current to one third. .

After a certain preheating time, after the temperature of the electric heating wire rises, the switching states of the first switch S1, the second switch S2 and the third switch S3 can be adjusted so that the first electric heating wire R1 and the second electric heating wire The wire R2 and the third electric heating wire R3 work in parallel and are in the second gear state, the third gear state, the fourth gear state and the fifth gear state respectively.

Among them, the second gear state is the first heating state of the vehicle electric heating wire preheating circuit;

The third gear state is the second gear heating state of the vehicle electric heating wire preheating circuit;

The fourth gear state is the third gear heating state of the vehicle electric heating wire preheating circuit;

The fifth gear state is the closed state of the vehicle's electric heating wire preheating circuit.

From the above description, it can be seen that when the vehicle heating wire preheating circuit is started in a cold state, the resistance is low and the power supply is directly based on the working voltage, which will produce a large inrush current. When the temperature of the heating wire rises, the resistance becomes larger and the current will recover. to normal operating current. This large inrush current can easily cause damage to various links in the power distribution circuit. When the vehicle electric heating wire preheating circuit provided by this application is started in the cold state, three electric heating wires are first connected in series and then connected to the working voltage. Then each heating wire is only connected to one-third of the working voltage, and the corresponding inrush current It can be reduced by one-third. After the temperature rises, the switching status of each switch is controlled according to the gear requirements. The corresponding heating wire is connected to the working voltage to work. While meeting the normal working requirements, the heating wire is effectively suppressed. cold start surge current.

Based on the above embodiments of the present invention, a control method is also provided in another embodiment of the present invention. Refer to Figure 3. Figure 3 is a schematic flow chart of a control method provided by an embodiment of the present invention. The control method includes:

S10: Determine whether the vehicle electric heating wire preheating circuit is in working condition;

S11: If yes, control the second switch to be in the on state, and the first switch and the third switch to be in the off state;

In this step, when the first switch and the third switch are in the off state and the second switch is in the on state, the first electric heating wire, the second electric heating wire and the third electric heating wire The electric heating wires are connected in series, which increases the loop resistance of the vehicle's electric heating wire preheating circuit and reduces the starting impulse current to one third.

S12: Determine whether the temperature of the vehicle electric heating wire preheating circuit reaches the preset temperature;

In this step, the preset temperature is not limited in the embodiment of the present invention and can be determined according to specific circumstances.

When the temperature of the vehicle electric heating wire preheating circuit reaches the preset temperature, it is the best time for the vehicle electric heating wire preheating circuit to work.

S13: If yes, receive the gear status command;

Wherein, the gear status instruction is used to control the switch status of the first switch, the second switch and the third switch.

In this step, the gear status command includes a first gear status command, a second gear status command, a third gear status command, a fourth gear status command, and a fifth gear status command;

Wherein, when the gear state command is the first gear state command, the first switch and the third switch are controlled to be in a cut-off state, and the second switch is controlled to be in a conductive state;

When the gear state instruction is the second gear state instruction, control the first switch to be in the on state, and the second switch and the third switch to be in the off state;

When the gear status command is a third gear status command, the first switch and the third switch are controlled to be in the on state, and the second switch is in the off state;

When the gear state instruction is the fourth gear state instruction, control the first switch, the second switch and the third switch to be in a conductive state;

When the gear state command is the fifth gear state command, the first switch, the second switch and the third switch are all controlled to be in a cut-off state.

Among them, the first gear status command is used to control the vehicle electric heating wire preheating circuit to be in a preheating state;

The second gear status command is used to control the vehicle electric heating wire preheating circuit to be in the first gear heating state;

The third gear status command is used to control the vehicle electric heating wire preheating circuit to be in the second gear heating state;

The fourth gear status command is used to control the vehicle electric heating wire preheating circuit to be in the third gear heating state;

The fifth gear status command is used to control the vehicle's electric heating wire preheating circuit to be in a closed state.

Further, the control method also includes:

If the vehicle electric heating wire preheating circuit is not in the working state, return to the step of determining whether the vehicle electric heating wire preheating circuit is in the working state.

Further, the control method also includes:

If the temperature of the vehicle electric heating wire preheating circuit does not reach the preset temperature, then return to the step of determining whether the temperature of the vehicle electric heating wire preheating circuit reaches the preset temperature.

Based on the above embodiments of the present invention, a control device is also provided in another embodiment of the present invention. Refer to Figure 4. Figure 4 is a schematic structural diagram of a control device provided by an embodiment of the present invention. The control device includes:

The first judgment module 41 is used to judge whether the vehicle electric heating wire preheating circuit is in a working state;

The first control module 42 is used to control the second switch to be in the on state, and the first switch and the third switch to be in the off state when the vehicle electric heating wire preheating circuit is in the working state;

The second judgment module 43 is used to judge whether the temperature of the vehicle electric heating wire preheating circuit reaches the preset temperature;

The second control module 44 is used to receive a gear status instruction when the temperature of the vehicle electric heating wire preheating circuit reaches a preset temperature; wherein the gear status instruction is used to control the first switch, the The switching status of the second switch and the third switch.

Further, the control device also includes: a third control module 45;

The third control module 45 is used to trigger the first judgment module 41 when the vehicle electric heating wire preheating circuit is not in a working state.

Further, the control device also includes: a fourth control module 46;

The fourth control module 46 is used to trigger the second judgment module 43 when the temperature of the vehicle electric heating wire preheating circuit does not reach a preset temperature.

If necessary, the principles of the control device and the control method are the same and will not be described again.

The vehicle electric heating wire preheating circuit, control method and control device provided by the present invention have been introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation modes of the present invention. The description of the above embodiments is only for reference. To help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the field, there will be changes in the specific implementation and application scope based on the idea of the present invention. In summary, this specification The contents should not be construed as limitations of the invention.

It should be noted that each embodiment in this specification is described in a progressive manner. Each embodiment focuses on its differences from other embodiments. The same and similar parts between the various embodiments are referred to each other. Can. As for the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple. For relevant details, please refer to the description in the method section.

It should also be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that these entities or operations There is no such actual relationship or sequence between them. Furthermore, the terms "comprises," "comprises," or any other variation thereof are intended to cover a non-exclusive inclusion such that a list of elements is inherent in, or is otherwise included in, a process, method, article, or apparatus. , elements inherent in a method, article or device. Without further limitation, an element defined by the statement "comprises a..." does not exclude the presence of additional identical elements in a process, method, article, or apparatus that includes the stated element.

The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be practiced in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (6)

1. A method for controlling a vehicle electric heating wire preheating circuit, characterized in that the vehicle electric heating wire preheating circuit includes: a first electric heating wire, a second electric heating wire, a third electric heating wire, a first switch, and a second switch. and a third switch; The first end of the first heating wire and the first end of the second heating wire are both connected to the first end of the first switch; The first end of the third electric heating wire is connected to the second end of the first switch, and the connection node between the first end of the third electric heating wire and the second end of the first switch serves as the vehicle electric heater. The input terminal of the wire preheating circuit; The second end of the third heating wire is connected to the first end of the second switch; the second end of the second switch is connected to the second end of the second heating wire and the third end of the third switch respectively. First end connection; The second end of the first electric heating wire is connected to the second end of the third switch, and the connection node between the second end of the first electric heating wire and the second end of the third switch serves as the vehicle electric heater. The output end of the wire preheating circuit; The vehicle electric heating wire preheating circuit includes a first gear state, a second gear state, a third gear state, a fourth gear state and a fifth gear state; The first gear state is the preheating state of the vehicle electric heating wire preheating circuit. When the vehicle electric heating wire preheating circuit is in the first gear state, the first switch and the third switch are in In the off state, the second switch is in the on state, and the first heating wire, the second heating wire and the third heating wire are connected in series; The second gear state is the first heating state of the vehicle electric heating wire preheating circuit. When the vehicle electric heating wire preheating circuit is in the second gear state, the first switch is in a conductive state, so The second switch and the third switch are in a cut-off state; The third gear state is the second gear heating state of the vehicle electric heating wire preheating circuit. When the vehicle electric heating wire preheating circuit is in the third gear state, the first switch and the third switch In the on state, the second switch is in the off state; The fourth gear state is the third gear heating state of the vehicle electric heating wire preheating circuit. When the vehicle electric heating wire preheating circuit is in the fourth gear state, the first switch and the second switch and the third switch are both in a conductive state; The fifth gear state is the closed state of the vehicle electric heating wire preheating circuit. When the vehicle electric heating wire preheating circuit is in the fifth gear state, the first switch, the second switch and the The third switches mentioned above are all in the off state; The control methods include: Determine whether the vehicle electric heating wire preheating circuit is in working condition; If so, control the second switch to be in the on state, and the first switch and the third switch to be in the off state; Determine whether the temperature of the vehicle electric heating wire preheating circuit reaches the preset temperature; If so, receive the gear status command; Wherein, the gear status instruction is used to control the switch status of the first switch, the second switch and the third switch. 2. The control method according to claim 1, characterized in that the control method further includes: If the vehicle electric heating wire preheating circuit is not in the working state, return to the step of determining whether the vehicle electric heating wire preheating circuit is in the working state. 3. The control method according to claim 1, characterized in that the control method further includes: If the temperature of the vehicle electric heating wire preheating circuit does not reach the preset temperature, then return to the step of determining whether the temperature of the vehicle electric heating wire preheating circuit reaches the preset temperature. 4. A control device, characterized in that the control device is used to execute the control method of the vehicle electric heating wire preheating circuit as claimed in claim 1, and the control device includes: The first judgment module is used to judge whether the vehicle electric heating wire preheating circuit is in working condition; A first control module, used to control the second switch to be in an on state, and the first switch and the third switch to be in an off state when the vehicle electric heating wire preheating circuit is in a working state; The second judgment module is used to judge whether the temperature of the vehicle electric heating wire preheating circuit reaches the preset temperature; The second control module is used to receive a gear status instruction when the temperature of the vehicle electric heating wire preheating circuit reaches a preset temperature; wherein the gear status instruction is used to control the first switch, the third switch, and the first switch. The switching status of the second switch and the third switch. 5. The control device according to claim 4, characterized in that the control device further includes: a third control module; The third control module is used to trigger the first judgment module when the vehicle electric heating wire preheating circuit is not in a working state. 6. The control device according to claim 4, characterized in that the control device further comprises: a fourth control module; The fourth control module is used to trigger the second judgment module when the temperature of the vehicle electric heating wire preheating circuit does not reach a preset temperature.