PWM-based high-voltage PTC heater control method and system

Abstract

The PWM-based high-voltage PTC heater control method comprises the following steps: acquiring a heating request instruction of a user, and analyzing the heating request instruction; according to the analyzed heating request instruction, whether an IGBT in the PTC heater executes peak shifting starting or not is judged; when an IGBT (Insulated Gate Bipolar Translator) in the PTC heater does not execute peak shifting starting, acquiring heating power requested by a user according to the analyzed heating request instruction; calculating the target heat of the PTC heater according to the heating power request of the user and the IGBT switching period; and according to the target heat of the PTC heater, a PWM value for controlling the switching time of the IGBT is adjusted, and control over the high-voltage PTC heater is achieved. By adopting a closed-loop control strategy, the on-off states of the plurality of IGBTs can be dynamically adjusted according to an external power request, so that accurate heat control is realized, and high-efficiency operation of the high-voltage PTC heater under various working conditions is ensured. Meanwhile, by optimizing the PWM frequency and adjusting the switching time, the noise is effectively reduced, and the user experience is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicles, and in particular to a PWM-based high-voltage PTC heater control method and system. Background Art

[0002] New energy electric vehicles are gradually becoming an important development direction of the automotive industry. One of the core technologies of new energy vehicles is an efficient thermal management system, in which high-voltage PTC (positive temperature coefficient) heaters play a key role in battery heating, air conditioning heating and other thermal management applications.

[0003] The working principle of PTC heater is to use the positive temperature coefficient characteristics of the material. When the current passes through the PTC material, as the temperature rises, its resistance also increases, thus achieving a self-regulating heating effect. This characteristic makes PTC heaters have the advantages of high safety, fast response and high efficiency in electric vehicles.

[0004] There are two main technologies in the control scheme of high-voltage PTC heaters: one is to divide the PTC core into multiple groups, each group is controlled by an IGBT (insulated gate bipolar transistor); the other is to use PWM (pulse width modulation) control technology. The former realizes the switching of power gears through different switch combinations. Although the structure is simple, it cannot realize arbitrary power adjustment and lacks flexibility. The latter realizes stepless power regulation by adjusting the opening time, which can quickly respond to different heating needs, but it is easy to generate noise under high-frequency operation. Summary of the invention

[0005] In view of the above problems, the present invention is proposed to provide a PWM-based high-voltage PTC heater control method and system that overcomes the above problems or at least partially solves the above problems.

[0006] In order to solve the above technical problems, the embodiments of the present application disclose the following technical solutions:

[0007] In a first aspect, an embodiment of the present invention discloses a PWM-based high-voltage PTC heater control method, comprising:

[0008] S100. Obtaining a user heating request instruction, and parsing the heating request instruction;

[0009] S200. According to the analyzed heating request instruction, it is determined whether the IGBT in the PTC heater is turned on at a staggered peak;

[0010] S300. When the IGBT in the PTC heater does not perform peak-shifting, the heating power requested by the user is obtained according to the resolved heating request instruction;

[0011] S400. Calculate the target heat of the PTC heater according to the user's heating power request and the IGBT switching cycle;

[0012] S500. According to the target heat of the PTC heater, the PWM value for controlling the IGBT switching time is adjusted to control the high-voltage PTC heater.

[0013] Furthermore, in S100, a user heating request instruction is obtained and the heating request instruction is parsed. The user heating request instruction at least includes a user-requested heating power and a user-requested heating position.

[0014] Further, in S200, based on the parsed heating request instruction, it is determined whether the IGBT in the PTC heater executes staggered start-up. The specific method includes: obtaining the user-requested heating position in the parsed heating request instruction, and determining whether the user-requested heating position is unique. If the user-requested heating position is unique, it is determined that the IGBT in the PTC heater does not need to execute staggered start-up; if the user-requested heating position is not unique, it is determined that the IGBT in the PTC heater needs to execute staggered start-up.

[0015] Further, in S300, when the IGBT in the PTC heater is turned on at a staggered peak, the IGBT at the corresponding position is turned on according to the heating position requested by the user, and the switching interval between each IGBT is set.

[0016] Further, in S400, the target heat of the PTC heater is calculated according to the heating power request of the user and the IGBT switching cycle. The specific method includes: obtaining the heating power request P0 and the IGBT switching cycle T of the user, then the target heat of the PTC heater Q0 = P0*T.

[0017] Further, in S500, the PWM value for controlling the IGBT switching time is adjusted according to the target heat of the PTC heater. The specific method includes: calculating the turn-on time a within the IGBT switching cycle T according to the current value I, voltage U and the target heat of the PTC heater when the IGBT is turned on, and then determining the PWM value for controlling the IGBT switching time according to the turn-on time a within the IGBT switching cycle T and the IGBT switching cycle T.

[0018] Furthermore, a specific method for calculating the on-time a within the IGBT switching cycle T includes:

[0019] The IGBT current is sampled in real time, the current value is collected every 1 millisecond, and the average current value is calculated every 100 milliseconds;

[0020] The current-time curve areas S1, S2, ..., Sn are calculated every 100 milliseconds using integral calculation, where:

[0021] Where f(t)d(t) is the current change value in the first 100 milliseconds;

[0022] The current-time curve area calculated every 100 milliseconds is accumulated to obtain a total area S=S1+S2+......+Sn; the total area S is multiplied by the voltage to obtain the actual heat Q1 of the IGBT;

[0023] Compare the actual heat Q1 and the target heat Q0. When the actual heat Q1 is less than the target heat Q0, the IGBT continues to be turned on; when the actual heat Q1 is greater than the target heat Q0, the IGBT is turned off to obtain the IGBT turn-on time a.

[0024] In a second aspect, an embodiment of the present invention discloses a PWM-based high-voltage PTC heater control system, comprising: a heating request instruction parsing unit, a peak-shifting start-up judgment unit, a heating power acquisition unit, a target heat calculation unit and a PWM value control unit; wherein:

[0025] A heating request instruction parsing unit, used for obtaining a user's heating request instruction and parsing the heating request instruction;

[0026] A peak-shift start-up judgment unit is used to judge whether the IGBT in the PTC heater performs peak-shift start-up according to the analyzed heating request instruction;

[0027] A heating power acquisition unit, used to acquire the heating power requested by the user according to the parsed heating request instruction when the IGBT in the PTC heater does not perform peak-shifting start-up;

[0028] A target heat calculation unit, used for calculating the target heat of the PTC heater according to the heating power request of the user and the IGBT switching cycle;

[0029] The PWM value control unit is used to adjust the PWM value for controlling the IGBT switching time according to the target heat of the PTC heater, so as to control the high-voltage PTC heater.

[0030] In a third aspect, an embodiment of the present invention discloses an electronic device, including:

[0031] one or more processors;

[0032] A memory for storing one or more programs;

[0033] When the one or more programs are executed by the one or more processors, the one or more processors implement the high-voltage PTC heater control method.

[0034] The beneficial effects of the above technical solution provided by the embodiment of the present invention include at least:

[0035] The present invention discloses a PWM-based high-voltage PTC heater control method, comprising: obtaining a user heating request instruction, parsing the heating request instruction; judging whether the IGBT in the PTC heater performs staggered opening according to the parsed heating request instruction; when the IGBT in the PTC heater does not perform staggered opening, obtaining the heating power requested by the user according to the parsed heating request instruction; calculating the target heat of the PTC heater according to the user's heating power request and the IGBT switching cycle; and adjusting the PWM value of the IGBT switching time according to the PTC heater target heat to achieve control of the high-voltage PTC heater. The present invention can dynamically adjust the switching state of multiple IGBTs according to external power requests by adopting a closed-loop control strategy, thereby achieving precise heat control and ensuring efficient operation of the high-voltage PTC heater under various working conditions. At the same time, by optimizing the PWM frequency and adjusting the switching time, the noise is effectively reduced and the user experience is improved. The present invention provides a new type of high-voltage PTC heater closed-loop control system and method, which has important technical significance and broad application prospects, and can significantly improve the thermal management performance of new energy vehicles.

[0036] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0038] Figure 1 This is a flow chart of a PWM-based high-voltage PTC heater control method in Example 1 of the present invention;

[0039] Figure 2 This is a schematic diagram of calculating the area under the current-time curve of the IGBT in Example 1 of the present invention;

[0040] Figure 3 This is a schematic diagram of the structure of an electronic device in Embodiment 2 of the present invention. DETAILED DESCRIPTION

[0041] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0042] In order to solve the problems existing in the prior art, an embodiment of the present invention provides a PWM-based high-voltage PTC heater control method and system.

[0043] Example 1

[0044] The present invention discloses a PWM-based high-voltage PTC heater control method. Figure 1 , including: S100. Obtain the user's heating request instruction and parse the heating request instruction; Specifically, in the automotive field, PTC (Positive Temperature Coefficient) heaters are widely used in various parts that need to be heated in automobiles. Due to their fast heating, high thermal efficiency and high safety, they are particularly suitable for use in automobile winter heating systems. Common PTC heater application locations in automobiles:

[0045] 1. Air conditioning system

[0046] Warm air system: In internal combustion engine vehicles, the heat of the engine coolant is usually used to provide warm air for the cabin, but in new energy vehicles (such as electric vehicles), PTC heaters become the main source of cabin warm air heating.

[0047] Anti-fog and defrost: Installing a PTC heater at the air outlet of the car's air-conditioning system can quickly defrost and defog the glass to ensure a clear view while driving.

[0048] 2. Seat heating

[0049] The PTC element installed inside the seat provides a fast and even heating effect for the seat. The PTC heater can self-regulate according to the temperature to avoid overheating, thus providing a comfortable riding experience.

[0050] 3. Battery heating system

[0051] In new energy vehicles, PTC heaters are used to heat the battery pack to ensure the normal operation of the battery in low temperature environments. The battery will reduce its activity at low temperatures, and the use of PTC heaters can improve the efficiency and life of the battery.

[0052] 4. Heated rearview mirror

[0053] Embedding PTC components in the rearview mirror can effectively prevent the mirror from frosting or fogging in winter, ensuring driving safety.

[0054] In S100 of this embodiment, a user heating request instruction is obtained and the heating request instruction is parsed. The user heating request instruction at least includes a user-requested heating power and a user-requested heating position.

[0055] S200. According to the parsed heating request instruction, determine whether the IGBT in the PTC heater performs staggered start-up; in the present embodiment S200, according to the parsed heating request instruction, determine whether the IGBT in the PTC heater performs staggered start-up, and the specific method includes: obtaining the user-requested heating position in the parsed heating request instruction, and determining whether the user-requested heating position is unique. If the user-requested heating position is unique, it is determined that the IGBT in the PTC heater does not need to perform staggered start-up; if the user-requested heating position is not unique, it is determined that the IGBT in the PTC heater needs to perform staggered start-up. Through the above method, it is possible to determine whether staggered start-up needs to be performed according to the parsed heating request instruction and priority, thereby reasonably controlling the start-up time of the IGBT of the PTC heater.

[0056] S300. When the IGBT in the PTC heater does not perform staggered start-up, the heating power requested by the user is obtained according to the parsed heating request instruction; in S300 of this embodiment, when the IGBT in the PTC heater performs staggered start-up, the IGBT at the corresponding position is turned on according to the heating position requested by the user, and the switching interval between each IGBT is set.

[0057] It is understandable that when the user needs to heat multiple partitions such as the driver's seat, the co-driver's seat, and the rear seat, multiple IGBTs need to be turned on at this time, and multiple IGBTs need to be turned on at staggered times. When multiple IGBTs are turned on at staggered times, it is necessary to set the staggered turn-on time of each IGBT. In this embodiment, the staggered turn-on time of each IGBT is preferably 2.5s.

[0058] S400. Calculate the target heat of the PTC heater according to the user's heating power request and the IGBT switching cycle; In S400, the target heat of the PTC heater is calculated according to the user's heating power request and the IGBT switching cycle. The specific method includes: obtaining the user's heating power request P0 and the IGBT switching cycle T, then the PTC heater target heat Q0 = P0*T. In this embodiment, the IGBT switching cycle is preferably 10s, and the IGBT switching frequency is 0.1Hz, which can effectively reduce the generation of noise, thereby improving the user experience. For example, the heating power request P0 in the user's heating request instruction is 100w, and the IGBT switching cycle T is 10s. Then, within one IGBT switching cycle T, the PTC heater target heat Q0 is 1000J.

[0059] S500. According to the target heat of the PTC heater, the PWM value for controlling the IGBT switching time is adjusted to achieve control of the high-voltage PTC heater. In S500 of this embodiment, according to the target heat of the PTC heater, the PWM value for controlling the IGBT switching time is adjusted, and the specific method includes: according to the current value I when the GBT is turned on, the voltage U and the target heat of the PTC heater, the turn-on time a within the IGBT switching cycle T is calculated, and then according to the turn-on time a within the IGBT switching cycle T and the IGBT switching cycle T, the PWM value for controlling the IGBT switching time is determined.

[0060] Among them, Figure 2 , the specific method for calculating the turn-on time a within the IGBT switching cycle T includes:

[0061] The IGBT current is sampled in real time, the current value is collected every 1 millisecond, and the average current value is calculated every 100 milliseconds;

[0062] The current-time curve areas S1, S2, ..., Sn are calculated every 100 milliseconds using integral calculation, where: Where f(t)d(t) is the current change value in the first 100 milliseconds;

[0063] The current-time curve area calculated every 100 milliseconds is accumulated to obtain a total area S=S1+S2+......+Sn; the total area S is multiplied by the voltage U to obtain the actual heat Q1 of the IGBT;

[0064] Compare the actual heat Q1 and the target heat Q0. When the actual heat Q1 is less than the target heat Q0, the IGBT continues to be turned on; when the actual heat Q1 is greater than the target heat Q0, the IGBT is turned off and the IGBT turn-on time a is obtained. Figure 2 When the product of the area and voltage of S1 is 200J, which is less than the target heat of 1000J, the IGBT needs to be kept turned on, and the product of the accumulated areas of S1 and S2 and the voltage is compared with the target heat until it is greater than or equal to the target heat. Then the IGBT is turned off and the IGBT turn-on time a is obtained.

[0065] After obtaining the IGBT on-time a and the IGBT switching cycle T, the PWM value that controls the IGBT switching time can be adjusted to achieve control of the high-voltage PTC heater. Among them, PWM (pulse width modulation) adjusts the output power or voltage by controlling the switching time ratio of the IGBT. This control method is particularly suitable for loads such as PTC heaters and DC motors that require precise current control. The key to PWM control is to adjust the duty cycle, that is, the time ratio of the IGBT to be turned on in a PWM cycle. PWM signals are usually generated by special PWM generators (such as PWM modules in PLCs). These generators can generate pulse signals with specified cycles and duty cycles. The generated PWM signal is transmitted to the gate of the IGBT through the drive circuit to control the opening and closing of the IGBT. When the pulse width of the PWM signal increases, the on-time ton of the IGBT also increases, the duty cycle α increases, and the on-time ratio of the IGBT increases; conversely, when the pulse width decreases, the on-time ton of the IGBT decreases, the duty cycle α decreases, and the on-time ratio of the IGBT decreases.

[0066] The present embodiment discloses a PWM-based high-voltage PTC heater control method, including: obtaining a user heating request instruction, parsing the heating request instruction; judging whether the IGBT in the PTC heater performs staggered opening according to the parsed heating request instruction; when the IGBT in the PTC heater does not perform staggered opening, obtaining the heating power requested by the user according to the parsed heating request instruction; calculating the target heat of the PTC heater according to the user's heating power request and the IGBT switching cycle; adjusting the PWM value of the IGBT switching time according to the PTC heater target heat to achieve control of the high-voltage PTC heater. The present invention can dynamically adjust the switching state of multiple IGBTs according to external power requests by adopting a closed-loop control strategy, thereby achieving precise heat control and ensuring efficient operation of the high-voltage PTC heater under various working conditions. At the same time, by optimizing the PWM frequency and adjusting the switching time, the noise is effectively reduced and the user experience is improved. The present invention provides a new type of high-voltage PTC heater closed-loop control system and method thereof, which has important technical significance and broad application prospects, and can significantly improve the thermal management performance of new energy vehicles.

[0067] Example 2

[0068] Based on the same inventive concept, the embodiment of the present disclosure also provides a PWM-based high-voltage PTC heater control system, including: a heating request instruction parsing unit, a peak-shifting start-up judgment unit, a heating power acquisition unit, a target heat calculation unit and a PWM value control unit; wherein:

[0069] A heating request instruction parsing unit, used for obtaining a user's heating request instruction and parsing the heating request instruction;

[0070] A peak-shift start-up judgment unit is used to judge whether the IGBT in the PTC heater performs peak-shift start-up according to the analyzed heating request instruction;

[0071] A heating power acquisition unit, used to acquire the heating power requested by the user according to the parsed heating request instruction when the IGBT in the PTC heater does not perform peak-shifting start-up;

[0072] A target heat calculation unit, used for calculating the target heat of the PTC heater according to the heating power request of the user and the IGBT switching cycle;

[0073] The PWM value control unit is used to adjust the PWM value for controlling the IGBT switching time according to the target heat of the PTC heater, so as to control the high-voltage PTC heater.

[0074] Among them, the specific working methods of the heating request instruction parsing unit, the peak-shifting start-up judgment unit, the heating power acquisition unit, the target heat calculation unit and the PWM value control unit have been recorded in detail in Example 1, and will not be repeated in this embodiment.

[0075] Example 3

[0076] Based on the same inventive concept, an embodiment of the present disclosure also provides an electronic device. Figure 3 FIG. 1 is a schematic diagram of the structure of an electronic device according to an embodiment of the present disclosure. Figure 2 As shown, an embodiment of the present disclosure provides an electronic device including: one or more processors 101, a memory 102, and one or more I / O interfaces 103. The memory 102 stores one or more programs, and when the one or more programs are executed by the one or more processors, the one or more processors implement any optimization method in the above embodiments; the one or more I / O interfaces 103 are connected between the processor and the memory, and are configured to implement information interaction between the processor and the memory.

[0077] Among them, the processor 101 is a device with data processing capabilities, including but not limited to a central processing unit (CPU), etc.; the memory 102 is a device with data storage capabilities, including but not limited to random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory (FLASH); the I / O interface (read-write interface) 103 is connected between the processor 101 and the memory 102, and can realize information interaction between the processor 101 and the memory 102, including but not limited to a data bus (Bus), etc.

[0078] In some embodiments, the processor 101 , the memory 102 , and the I / O interface 103 are connected to each other via a bus 104 , and further connected to other components of the computing device.

[0079] In some embodiments, the one or more processors 101 include a field programmable gate array.

[0080] According to an embodiment of the present disclosure, a computer-readable medium is further provided, wherein a computer program is stored on the computer-readable medium, wherein when the program is executed by a processor, the steps in any optimization method in the above-mentioned embodiment are implemented.

[0081] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of protection of the present disclosure. The attached method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0082] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are clearly stated in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0083] Those skilled in the art will also appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the embodiments herein can all be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the interchangeability between hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above around their functions. Whether such functions are implemented as hardware or software depends on specific applications and the design constraints imposed on the entire system. A skilled person can implement the described functions in an alternative manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection of the present disclosure.

[0084] The steps of the method or algorithm described in conjunction with the embodiments herein may be directly embodied as hardware, a software module executed by a processor, or a combination thereof. The software module may be located in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a mobile disk, a CD-ROM, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor so that the processor can read information from the storage medium and can write information to the storage medium. Of course, the storage medium may also be an integral part of the processor. The processor and the storage medium may be located in an ASIC. The ASIC may be located in a user terminal. Of course, the processor and the storage medium may also be present in a user terminal as discrete components.

[0085] For software implementation, the techniques described in this application can be implemented with modules (e.g., procedures, functions, etc.) that perform the functions described in this application. These software codes can be stored in a memory unit and executed by a processor. The memory unit can be implemented within the processor or outside the processor. In the latter case, it is coupled to the processor in a communication manner via various means, which are well known in the art.

[0086] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," is explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or".

Claims

1. A PWM-based high-voltage PTC heater control method, characterized in that: include: S100. Obtaining a user heating request instruction, and parsing the heating request instruction; S200. According to the analyzed heating request instruction, it is determined whether the IGBT in the PTC heater is turned on at a staggered peak; S300. When the IGBT in the PTC heater does not perform peak-shifting, the heating power requested by the user is obtained according to the resolved heating request instruction; S400. Calculate the target heat of the PTC heater according to the user's heating power request and the IGBT switching cycle; S500. According to the target heat of the PTC heater, the PWM value for controlling the IGBT switching time is adjusted to control the high-voltage PTC heater.

2. A PWM-based high-voltage PTC heater control method as claimed in claim 1, characterized in that: In S100, a user heating request instruction is obtained and the heating request instruction is parsed. The user heating request instruction at least includes a user-requested heating power and a user-requested heating position.

3. A PWM-based high-voltage PTC heater control method as claimed in claim 1, characterized in that: In S200, based on the parsed heating request instruction, it is determined whether the IGBT in the PTC heater executes staggered start-up. The specific method includes: obtaining the user-requested heating position in the parsed heating request instruction, and determining whether the user-requested heating position is unique. If the user-requested heating position is unique, it is determined that the IGBT in the PTC heater does not need to execute staggered start-up; if the user-requested heating position is not unique, it is determined that the IGBT in the PTC heater needs to execute staggered start-up.

4. A PWM-based high-voltage PTC heater control method as claimed in claim 1, characterized in that: In S300, when the IGBT in the PTC heater is turned on at a staggered peak, the IGBT at the corresponding position is turned on according to the user's request for heating, and the switching interval between each IGBT is set.

5. A PWM-based high-voltage PTC heater control method as claimed in claim 1, characterized in that: In S400, the target heat of the PTC heater is calculated according to the heating power request of the user and the IGBT switching cycle. The specific method includes: obtaining the heating power request P0 and the IGBT switching cycle T of the user, then the target heat of the PTC heater Q0 = P0*T.

6. A PWM-based high-voltage PTC heater control method as claimed in claim 1, characterized in that: In S500, the PWM value for controlling the IGBT switching time is adjusted according to the target heat of the PTC heater. The specific method includes: calculating the turn-on time a within the IGBT switching cycle T according to the current value I, voltage U and the target heat of the PTC heater when the IGBT is turned on, and then determining the PWM value for controlling the IGBT switching time according to the turn-on time a within the IGBT switching cycle T and the IGBT switching cycle T.

7. A PWM-based high-voltage PTC heater control method as claimed in claim 6, characterized in that: The specific method for calculating the on-time a within the IGBT switching cycle T includes: The IGBT current is sampled in real time, the current value is collected every 1 millisecond, and the average current value is calculated every 100 milliseconds; The current-time curve areas S1, S2, ..., Sn are calculated every 100 milliseconds using integral calculation, where: Where f(t)d(t) is the current change value in the first 100 milliseconds; The current-time curve area calculated every 100 milliseconds is accumulated to obtain a total area S=S1+S2+......+Sn; the total area S is multiplied by the voltage U to obtain the actual heat Q1 of the IGBT; Compare the actual heat Q1 and the target heat Q0. When the actual heat Q1 is less than the target heat Q0, the IGBT continues to be turned on; when the actual heat Q1 is greater than the target heat Q0, the IGBT is turned off to obtain the IGBT turn-on time a.

8. A PWM-based high-voltage PTC heater control system, characterized in that: include: Heating request instruction parsing unit, peak-shifting start judgment unit, heating power acquisition unit, target heat calculation unit and PWM value control unit; wherein: A heating request instruction parsing unit, used for obtaining a user's heating request instruction and parsing the heating request instruction; A peak-shift start-up judgment unit is used to judge whether the IGBT in the PTC heater performs peak-shift start-up according to the analyzed heating request instruction; A heating power acquisition unit, used to acquire the heating power requested by the user according to the parsed heating request instruction when the IGBT in the PTC heater does not perform peak-shifting start-up; A target heat calculation unit, used for calculating the target heat of the PTC heater according to the heating power request of the user and the IGBT switching cycle; The PWM value control unit is used to adjust the PWM value for controlling the IGBT switching time according to the target heat of the PTC heater, so as to control the high-voltage PTC heater.

9. An electronic device, comprising: one or more processors; A memory for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the high-voltage PTC heater control method.

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