Control method for controlling double-wind PTC based on double IGBTs

Abstract

The invention discloses a control method for controlling a double-wind PTC (Positive Temperature Coefficient) based on double IGBTs (Insulated Gate Bipolar Translator), and belongs to the technical field of control for controlling the double-wind PTC based on the double IGBTs, the double IGBTs are adopted to control a circuit for controlling the double-wind PTC to control a first PTC and a second PTC to work, and the circuit for controlling the double-wind PTC based on the double IGBTs comprises a first IGBT, a second IGBT, the first PTC, the second PTC, a first PWM (Pulse Width Modulation) end, a second PWM end and an HV end; through on-off of the IGBT, the PTC can be controlled to work at more gears, and the situation that only a high-temperature scheme can be adopted when the air volume is low and the temperature is high is avoided. Due to the fact that the characteristics of the PTC and the heating power of the PTC are related to the passing current, the size of the current passing through the PTC can be controlled through the IGBT, then the output power of the PTC can be effectively controlled, the linear problem of the heating temperature of the air conditioner can be solved, and the damage risk of the HVAC shell under the conditions of low air volume and high temperature can also be solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of manual air-conditioning control, and in particular relates to a control method based on dual IGBTs controlling dual-wind PTCs. Background Art

[0002] With the rapid development of electric vehicles, the current sales of electric vehicles are catching up with or even surpassing the trend of traditional vehicles. Traditional car air conditioning heating generally uses engine hot water for heating. However, electric vehicles do not have engines, so heating is generally carried out by using PTC heaters. At present, due to cost considerations, there are many manual air conditioning solutions for electric vehicles. Therefore, for air conditioning heating, relays are generally used to control the on and off of PTC, which poses a great risk to the comfort of the air conditioner and the safety performance of the HVAC housing.

[0003] The existing solution generally uses relays to control PTC. When relay 1 is closed, PTC1 starts to work; when relay 2 is closed, PTC2 starts to work. When the two relays are closed at the same time, the two PTCs can work at the same time. The advantages of this solution are simple control and the air conditioner heating gear can be increased. The comfort of the air conditioner can be adjusted to a certain extent.

[0004] However, the biggest disadvantages of this solution are: ① The three-level temperature adjustment is intelligent, and the air conditioning temperature division is unclear; ② When the air conditioning controller selects low air volume and high temperature, it is generally necessary to turn on two PTCs, but at this time, due to the low air volume. The HVAC is a plastic shell, the temperature inside the cavity is too high, and the plastic parts around the PTC are at risk of melting. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a control method based on dual IGBT controlling dual-wind PTC in response to the shortcomings of the background technology; a dual IGBT controlling dual-wind PTC circuit is used to control the operation of two PTCs, the PTC is started in a simulated PWM form, and the PTC gear position is controlled by IGBT disconnection.

[0006] The present invention adopts the following technical solutions to solve the above technical problems:

[0007] A control method based on dual IGBT controlling dual-wind PTC, using a dual IGBT controlling dual-wind PTC circuit to control the operation of two PTCs, simulating PWM to start PTC, and controlling the PTC gear position operation by IGBT disconnection;

[0008] The dual-IGBT controlled dual-wind PTC circuit comprises a first IGBT, a second IGBT, a first PTC, a second PTC, a first PWM terminal, a second PWM terminal, and a HV terminal; wherein the gate of the first IGBT is connected to the first PWM terminal, the collector of the first IGBT is connected to the HV terminal, the base of the first IGBT is connected to the positive electrode of the first PTC, the gate of the second IGBT is connected to the second PWM terminal, the collector of the second IGBT is connected to the HV terminal, the base of the second IGBT is connected to the positive electrode of the second PTC, and the negative electrode of the first PTC and the negative electrode of the second PTC are grounded.

[0009] As a further preferred solution of the control method based on dual IGBT controlling dual-wind PTC of the present invention, the PTC gear includes a temperature gear and an air volume gear.

[0010] As a further preferred solution of the control method based on dual IGBT controlling dual-wind PTC of the present invention, the temperature gear includes three gears.

[0011] As a further preferred solution of the control method based on dual IGBT controlling dual wind PTC of the present invention, the air volume gear includes four gears.

[0012] Compared with the prior art, the present invention adopts the above technical solution and has the following technical effects:

[0013] A control method based on dual IGBT controlling dual-wind PTC adopts two IGBTs to control the operation of two PTCs. At this time, the PTC can be started in a simulated PWM form. By switching on and off the IGBT, the PTC can be controlled to work in more gears to avoid low air volume and high temperature, when only a high temperature solution can be used. Due to the characteristics of PTC, the heating power of PTC is related to the current passing through it. Therefore, by using IGBT, the current passing through PTC can be controlled, and then the output power of PTC can be effectively controlled. This can not only solve the problem of linear heating temperature of air conditioner, but also solve the risk of damage to HVAC shell under low air volume and high temperature. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a PTC circuit diagram of a relay controlling the PTC of the present invention;

[0015] Figure 2 It is the gear logic of the relay scheme of the present invention;

[0016] Figure 3 This is the IGBT control PTC circuit diagram of the present invention;

[0017] Figure 4 This is the IGBT solution control logic of the present invention. DETAILED DESCRIPTION

[0018] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings:

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. The present invention is described in detail below based on the drawings and preferred embodiments, and the purpose and effect of the present invention will become clearer. It should be understood that the specific embodiments described here are only used to explain the present invention and are not used to limit the present invention.

[0020] like Figure 1 and Figure 2 As shown, the existing scheme generally uses relays to control PTC. When relay 1 is closed, PTC1 starts to work; when relay 2 is closed, PTC2 starts to work. When the two relays are closed at the same time, the two PTCs can work at the same time. The advantages of this scheme are simple control and the air conditioner heating gear can be increased. The comfort of the air conditioner can be adjusted to a certain extent.

[0021] However, the biggest disadvantages of this solution are: ① The three-level temperature adjustment is intelligent, and the air conditioning temperature division is unclear; ② When the air conditioning controller selects low air volume and high temperature, it is generally necessary to turn on two PTCs, but at this time, due to the low air volume. The HVAC is a plastic shell, the temperature inside the cavity is too high, and the plastic parts around the PTC are at risk of melting.

[0022] Implementation plan: Figure 3 and Figure 4 As shown, a control method based on dual IGBT controlling dual-wind PTC is adopted in the present invention. Two IGBTs are adopted to control the operation of two PTCs. At this time, the PTC can be started in a simulated PWM form. By switching on and off the IGBTs, the PTC can be controlled to work in more gears, avoiding low air volume and high temperature, when only a high temperature solution can be adopted.

[0023] The dual-IGBT controlled dual-wind PTC circuit comprises a first IGBT, a second IGBT, a first PTC, a second PTC, a first PWM terminal, a second PWM terminal, and a HV terminal; wherein the gate of the first IGBT is connected to the first PWM terminal, the collector of the first IGBT is connected to the HV terminal, the base of the first IGBT is connected to the positive electrode of the first PTC, the gate of the second IGBT is connected to the second PWM terminal, the collector of the second IGBT is connected to the HV terminal, the base of the second IGBT is connected to the positive electrode of the second PTC, and the negative electrode of the first PTC and the negative electrode of the second PTC are grounded.

[0024] According to the above scheme, due to the characteristics of PTC, the heating power of PTC is related to the current passing through it. Therefore, by using IGBT, the current passing through PTC can be controlled, and then the output power of PTC can be effectively controlled, which can not only solve the linear problem of air conditioning heating temperature, but also solve the risk of HVAC casing damage under low air volume and high temperature.

[0025] Those skilled in the art can understand that the above are only preferred examples of the invention and are not intended to limit the invention. Although the invention is described in detail with reference to the above examples, those skilled in the art can still modify the technical solutions recorded in the above examples or replace some of the technical features with equivalents. Any modification, equivalent replacement, etc. made within the spirit and principle of the invention should be included in the protection scope of the invention. All technical features in this embodiment can be freely combined according to actual needs.

[0026] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A control method based on dual IGBT controlling dual wind PTC, characterized in that: The dual-IGBT control dual-wind PTC circuit is used to control the operation of two PTCs, and the PTC is started in a simulated PWM form, and the PTC gear position is controlled by IGBT disconnection; The dual-IGBT controlled dual-wind PTC circuit comprises a first IGBT, a second IGBT, a first PTC, a second PTC, a first PWM terminal, a second PWM terminal, and a HV terminal; wherein the gate of the first IGBT is connected to the first PWM terminal, the collector of the first IGBT is connected to the HV terminal, the base of the first IGBT is connected to the positive electrode of the first PTC, the gate of the second IGBT is connected to the second PWM terminal, the collector of the second IGBT is connected to the HV terminal, the base of the second IGBT is connected to the positive electrode of the second PTC, and the negative electrode of the first PTC and the negative electrode of the second PTC are grounded.

2. The control method based on dual IGBT controlling dual PTC according to claim 1 is characterized in that: The PTC gears include a temperature gear and an air volume gear.

3. The control method based on dual IGBT controlling dual PTC according to claim 1, characterized in that: The temperature gear includes three gears.

4. The control method based on dual IGBT controlling dual PTC according to claim 1, characterized in that: The air volume gear includes four gears.

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