Low-temperature starting control method of charger in charging mode, controller and medium

Abstract

The invention provides a low-temperature starting control method of a charger in a charging mode, a controller and a medium. The method comprises the steps of obtaining real-time impedance of a bus capacitor according to input alternating current, a real-time duty ratio and real-time voltage of the bus capacitor; obtaining the maximum allowable output power of the charger according to the real-time impedance of the bus capacitor, the real-time voltage of the bus capacitor and / or a pre-obtained corresponding relation between the impedance of the bus capacitor and the maximum output power; and controlling the charger to take the maximum allowable output power as the output power thereof. According to the method, the bus capacitor can be heated with the maximum safety ripple, the risk that the bus capacitor is damaged due to the fact that the output power of the charger is too high due to calibration errors can be remarkably reduced, the low-temperature starting time can be shortened, and the user experience is improved; meanwhile, the method is simple in logic and easy to implement.

Description

Technical Field

[0001] The present invention relates to the field of charger control technology, and in particular to a low-temperature startup control method, a controller, and a medium for a charger in a charging mode. Background Art

[0002] See Figure 1 , Figure 1 FIG. 1 is a block diagram of a vehicle-mounted charger in the prior art (taking an isolated vehicle-mounted charger as an example). Figure 1 As shown, the on-board charger in the prior art generally includes two power components: a first conversion circuit 110 (such as a power factor correction circuit, PFC) and a second conversion circuit 120 (such as a bidirectional DC / DC converter). The first conversion circuit 110 is responsible for converting AC (Alternating Current) voltage into DC (Direct Current) voltage, and the second conversion circuit 120 is responsible for converting DC voltage into the voltage range of the high-voltage battery 130, thereby charging the high-voltage battery 130. Since the AC end power fluctuates at twice the frequency of the power grid, in order to avoid the impact of power fluctuations on the second conversion circuit 120 located in the subsequent stage, a large-capacity bus capacitor C is usually added between the first conversion circuit 110 located in the previous stage and the second conversion circuit 120 located in the subsequent stage. Bus When the bus capacitor C Bus When the impedance is large, if the output power of the on-board charger is too large, the bus capacitor ripple will be severe, which may cause the bus capacitor C Bus Failure or triggering of bus capacitor C Bus Overvoltage or undervoltage faults may even cause the onboard charger to shut down. Therefore, when starting the charger at low temperatures, it is necessary to adjust the bus capacitance C Bus output in the state of derating.

[0003] In the prior art, there are two main known low-temperature startup control schemes for on-board chargers:

[0004] (1) When the on-board charger is started at low temperature, the output power of the on-board charger is limited to start at a lower power, and the output power of the on-board charger is gradually released according to the running time. This method requires calibration of the starting time of the on-board charger at different power levels at low temperatures. However, this method still has the following defects: if the calibrated power is too large, there is a risk of damaging the bus capacitor; if the limited power is too small, it will affect the starting time of the on-board charger at full load.

[0005] (2), the vehicle charger in low temperature start, detect the voltage fluctuation of bus capacitor, when the voltage fluctuation of bus capacitor is less than the safety value, increase the output power of vehicle charger, when the voltage fluctuation of bus capacitor is greater than the safety voltage value, reduce the output power of vehicle charger.However, through research, it is found that the method has the following defects: when the power of the vehicle charger increases or decreases, the voltage fluctuation of the bus capacitor will be caused, which is easy to cause the output power of the vehicle charger to fluctuate sharply.

[0006] It should be noted that the information disclosed in the background section of the present application is only intended to deepen the understanding of the general background of the present application, and should not be regarded as acknowledging or implying in any form that the information constitutes prior art known to those skilled in the art. SUMMARY

[0007] The purpose of the present application is to provide a charger charging mode low temperature start control method, controller and medium, the present application can heat the bus capacitor with the maximum safety ripple, not only can significantly reduce the risk of bus capacitor damage caused by the output power of the charger being too high due to the calibration error, but also can speed up the low temperature start time and improve the user experience; at the same time, the logic of the present application is simple and easy to implement.

[0008] In order to achieve the above purpose, the present application realizes the following technical scheme, a charger charging mode low temperature start control method, the charger includes a first conversion circuit for converting alternating voltage into direct current voltage, bus capacitor and a second conversion circuit for converting the direct current voltage into the required voltage range of load, the method comprises:

[0009] According to the alternating current input to the first conversion circuit, the real-time duty cycle of the first conversion circuit and the real-time voltage of the bus capacitor, the real-time impedance of the bus capacitor is obtained;

[0010] According to the real-time impedance of the bus capacitor, and the real-time voltage of the bus capacitor and / or the corresponding relationship between the pre-acquired bus capacitor impedance and the maximum output power, the maximum allowed output power of the charger is obtained;

[0011] The charger is controlled to take the maximum allowed output power as its output power.

[0012] Optionally, the real-time impedance of the bus capacitor is obtained according to the alternating current input to the first conversion circuit, the real-time duty cycle of the first conversion circuit and the real-time voltage of the bus capacitor, comprising:

[0013] According to the alternating current and the real-time duty cycle of the first conversion circuit, the ripple current effective value of the bus capacitor is obtained;

[0014] According to the real-time voltage of the bus capacitor, a ripple voltage effective value of the bus capacitor is obtained;

[0015] According to the ripple voltage effective value and the ripple current effective value, an impedance estimation value of the bus capacitor is obtained.

[0016] Optionally, the obtaining of the ripple current effective value of the bus capacitor according to the alternating current and the real-time duty cycle of the first conversion circuit comprises:

[0017] According to the alternating current and the real-time duty cycle of the first conversion circuit, a current estimation value of the bus capacitor is obtained;

[0018] The current estimation value is band-pass filtered at a 2 times frequency of the alternating voltage, and a ripple current effective value of the bus capacitor is obtained according to the filtered current estimation value.

[0019] Optionally, the obtaining of the ripple voltage effective value of the bus capacitor according to the real-time voltage of the bus capacitor comprises:

[0020] The real-time voltage of the bus capacitor is band-pass filtered at a 2 times frequency of the alternating voltage, and a ripple voltage effective value of the bus capacitor is obtained according to the filtered real-time voltage.

[0021] Optionally, the obtaining of the maximum allowed output power of the charger according to the real-time impedance of the bus capacitor and the real-time voltage of the bus capacitor comprises:

[0022] The real-time voltage of the bus capacitor is notch filtered at a 2 times frequency of the alternating voltage, and a direct current voltage component of the bus capacitor is obtained according to a direct current voltage component;

[0023] According to the real-time impedance of the bus capacitor, the direct current voltage component and a maximum allowed ripple voltage preset peak value of the bus capacitor, a maximum allowed output power of the charger is obtained.

[0024] Optionally, the obtaining of the maximum allowed output power of the charger according to the real-time impedance of the bus capacitor, the direct current voltage component and the maximum allowed ripple voltage preset peak value of the bus capacitor comprises:

[0025] The smaller one between the real-time impedance and the real-time impedance of the bus capacitor at a previous time is taken as an effective impedance of the bus capacitor; wherein the initial value of the real-time impedance at the previous time is greater than or equal to 10Ω and less than or equal to 99Ω;

[0026] According to the effective impedance, the direct current voltage component and the maximum allowed ripple voltage preset peak value of the bus capacitor, a maximum allowed output power of the charger is obtained.

[0027] Optionally, the maximum allowed ripple voltage preset peak value is greater than or equal to 40V and less than or equal to 60V.

[0028] Optionally, the correspondence between the bus capacitor impedance and the maximum output power is obtained through calibration.

[0029] In order to achieve the above-mentioned purpose, the application further provides a vehicle controller, which comprises a processor and a memory, wherein the memory stores a computer program, and the computer program is executed by the processor to realize the low-temperature starting control method of the charger in the charging mode.

[0030] In order to achieve the above-mentioned purpose, the application further provides a readable storage medium, which stores a computer program, and the computer program is executed by a processor to realize the low-temperature starting control method of the charger in the charging mode.

[0031] Compared with the prior art, the low-temperature starting control method of the charger in the charging mode, the controller and the medium provided by the application have the following advantages:

[0032] The low-temperature starting control method of the charger in the charging mode provided by the application obtains the real-time impedance of the bus capacitor according to the alternating current input to the first conversion circuit, the real-time duty cycle of the first conversion circuit and the real-time voltage of the bus capacitor, and obtains the maximum allowed output power of the charger according to the real-time impedance of the bus capacitor, the real-time voltage of the bus capacitor and / or the correspondence between the bus capacitor impedance and the maximum output power obtained in advance, and finally controls the charger to output the maximum allowed output power. As can be seen, the application does not need to be calibrated, and only needs to calculate the maximum output power under the safe voltage of the bus capacitor according to the real-time state of the bus capacitor through the real-time impedance of the bus capacitor, so as to limit the output power of the charger. By such configuration, the application can heat the bus capacitor with the maximum safe ripple, which not only can significantly reduce the risk of damage to the bus capacitor caused by the over-high output power of the charger due to the calibration error, but also can speed up the low-temperature starting time and improve the user experience; at the same time, the application has simple logic and is easy to implement.

[0033] Since the vehicle controller and the readable storage medium provided by the present application belong to the same inventive concept as the low-temperature starting control method in the charging mode of the charging machine provided by the present application, the vehicle controller and the readable storage medium provided by the present application at least have all the advantages of the low-temperature starting control method in the charging mode of the charging machine provided by the present application. For the details of the beneficial effects of the vehicle controller and the readable storage medium provided by the present application, please refer to the relevant description of the beneficial effects of the low-temperature starting control method in the charging mode of the charging machine provided by the present application. Here, it will not be described one by one. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 It is a block structure schematic diagram of the vehicle-mounted charging machine in the prior art;

[0035] Figure 2 It is a general flowchart of the low-temperature starting control method in the charging mode of the charging machine provided by the present application;

[0036] Figure 3 It is a schematic diagram of a specific example of obtaining the real-time impedance of the bus capacitor in the present application;

[0037] Figure 4 It is a schematic diagram of a specific example of obtaining the maximum allowed output power in the present application;

[0038] Figure 5 It is a block structure schematic diagram of the vehicle controller provided by one of the embodiments of the present application;

[0039] Among them, the reference signs are as follows:

[0040] First conversion circuit-110, second conversion circuit-120, bus capacitor-C Bus , high-voltage battery-130;

[0041] Processor-210, memory-220, communication interface-230, communication bus-240. DETAILED DESCRIPTION

[0042] The low temperature starting control method, controller and medium of the charger under the charging mode of the charger according to the present application are described in further detail below in conjunction with the accompanying drawings. The advantages and features of the present application will be more apparent from the following description. It should be noted that the drawings are very simplified and all use non-precise proportions, only for the purpose of facilitating, clarifying the purpose of assisting in the description of the embodiments of the present application. In order to make the purpose, features and advantages of the present application more obvious and easy to understand, please refer to the accompanying drawings. It should be noted that the structure, proportion, size, etc. shown in the drawings of the present application are only used to cooperate with the content disclosed in the specification, so that those skilled in the art can understand and read, and are not used to limit the implementation of the present application. Any modification of structure, change of proportion relationship or adjustment of size, as long as it is the same or similar to the effect and purpose that can be achieved by the present application, should still fall within the scope of the technical content disclosed by the present application. The specific design features of the present application disclosed herein include, for example, specific dimensions, directions, positions and shapes, which will be determined in part by the specific environment to be applied and used. In addition, in the embodiments described below, the same reference signs are sometimes used between different drawings to represent the same parts or parts with the same function, and the repeated description is omitted. In this specification, similar signs and letters are used to represent similar items, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings. In addition, if the method described herein includes a series of steps, and the order of the steps presented herein is not necessarily the only order in which the steps can be performed, and some of the described steps can be omitted and / or some other steps not described herein can be added to the method.

[0043] It should be noted that the relational terms herein, such as first and second, and the like, are used solely to distinguish one from another entity or action without necessarily requiring or implying any actual relationship or order between such entities or actions. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises... a" does not, without more constraints, exclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element. The singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise. The term "or" is generally employed in its sense including "and / or" unless the context clearly dictates otherwise. The term "and / or" means "and" or "or". The term "at least two" is generally employed in its sense including "two or more" unless the context clearly dictates otherwise. The terms "first", "second", "third", etc., are used only to describe a purpose and cannot be understood as indicating or implying relative importance or implying a number of the indicated technical features.

[0044] In addition, unless specifically stated or otherwise evident from context, as used herein, the term "about" is understood not to require exact numerical precision, but rather allows for some leeway in the value. "About" can be understood to be within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated value. Unless otherwise explicitly stated from context, all numerical values provided herein are modified by the term "about".

[0045] The core idea of the present application is to provide a charging machine charging mode low temperature start control method, controller and medium, the present application can heat the bus capacitor with the maximum safety ripple, not only can significantly reduce the risk of bus capacitor damage caused by the output power of the charging machine being too high due to the calibration error, but also can speed up the low temperature start time and improve the user experience; at the same time, the logic of the present application is simple and easy to implement.

[0046] It should be noted that the charging machine charging mode low temperature start control method provided by the present application does not make any limitation on the type of charging machine. For example, the charging machine charging mode low temperature start control method provided by the present application can be applied to vehicle-mounted charging machines and non-vehicle-mounted charging machines. Further, the present application does not make too many limitations on the topology structure of the PFC (power factor correction circuit) of the charging machine. For example, the present application can be applied to, but is not limited to, totem column PFC, voltage doubling PFC and frequency multiplication PFC, etc.

[0047] It should be understood that the low-temperature starting control method in the charging mode of the charger and the readable storage medium provided by the present application can be applied to the vehicle controller provided by the present application, and the low-temperature starting control method in the charging mode of the charger, the vehicle controller and the readable storage medium provided by the present application can be applied to the vehicle. It should be understood that the term "vehicle" or "vehicle" or other similar terms used herein include general motor vehicles, for example, passenger vehicles including but not limited to sport utility vehicles (SUV), buses, trucks, various commercial vehicles.

[0048] In order to realize the above idea, one embodiment of the present application provides a low-temperature starting control method in the charging mode of a charger. As shown in Figure 1 The charger includes a first conversion circuit 110 for converting an alternating voltage into a direct voltage, a bus capacitor C Bus and a second conversion circuit 120 for converting the direct voltage into a voltage range required by a load. For example, please refer to Figure 2 which schematically shows the overall flowchart of the low-temperature starting control method in the charging mode of the charger provided by the present embodiment. From Figure 2 It can be seen that the low-temperature starting control method in the charging mode of the charger includes the following steps:

[0049] S100: obtaining the real-time impedance of the bus capacitor according to the alternating current input to the first conversion circuit, the real-time duty cycle of the first conversion circuit, and the real-time voltage of the bus capacitor;

[0050] S200: obtaining the maximum allowable output power of the charger according to the real-time impedance of the bus capacitor, and the real-time voltage of the bus capacitor and / or the corresponding relationship between the pre-acquired bus capacitor impedance and the maximum output power;

[0051] S300: controlling the charger to take the maximum allowable output power as its output power.

[0052] Therefore, the low-temperature starting control method of the charger in the charging mode provided by the application obtains the real-time impedance of the bus capacitor according to the AC current input to the first conversion circuit, the real-time duty cycle of the first conversion circuit, and the real-time voltage of the bus capacitor, and obtains the maximum allowable output power of the charger according to the real-time impedance of the bus capacitor, and the corresponding relationship between the real-time voltage of the bus capacitor and / or the bus capacitor impedance obtained in advance and the maximum output power, and finally controls the charger to take the maximum allowable output power as the output power thereof. As can be seen, the application does not need to be calibrated, and only needs to obtain the real-time impedance of the bus capacitor to more directly calculate the maximum output power under the safe voltage of the bus capacitor according to the real-time state of the bus capacitor, so as to limit the output power of the charger. In this way, the application can heat the bus capacitor with the maximum safe ripple, which not only can significantly reduce the risk of damage to the bus capacitor caused by the over-high output power of the charger due to the calibration error, but also can speed up the low-temperature starting time and improve the user experience; at the same time, the logic of the application is simple and easy to implement.

[0053] First of all, it should be noted that the application does not make too many limitations on the first conversion circuit. For example, if the first conversion circuit is a three-phase PFC, the bus capacitor impedance value can be extracted and the output power can be calculated according to the application if the bus capacitor voltage is fluctuated at a certain low frequency. For example, the application is also applicable to the bus capacitor heating in the constant voltage output mode of the charger.

[0054] Secondly, in order to facilitate the understanding of the application, the step S200 is specifically described as follows:

[0055] In the first embodiment, the maximum allowable output power of the charger can be obtained according to the real-time impedance of the bus capacitor and the real-time voltage of the bus capacitor. Therefore, the application has better control accuracy. The embodiment will be described in detail below, which is not expanded here.

[0056] In the second embodiment, the maximum allowed output power of the charger can be obtained according to the real-time impedance of the bus capacitor and a pre-obtained corresponding relationship between the bus capacitor impedance and the maximum output power. In this way, the logic of the present application can be made simpler. It should be understood by those skilled in the art that the present application does not make any limitation on the specific obtaining method of the corresponding relationship between the bus capacitor impedance and the maximum output power. Preferably, the corresponding relationship between the bus capacitor impedance and the maximum output power can be obtained through calibration. It should be further understood that the present application does not make any limitation on the specific expression of the corresponding relationship between the bus capacitor impedance and the maximum output power. For example, in some embodiments, the corresponding relationship between the bus capacitor impedance and the maximum output power can be a corresponding relationship table, in which case, the maximum allowed output power of the charger can be obtained by looking up the corresponding relationship table according to the real-time impedance of the bus capacitor; in other embodiments, the corresponding relationship between the bus capacitor impedance and the maximum output power can be a function relationship, in which case, the maximum allowed output power of the charger can be obtained by substituting the real-time impedance of the bus capacitor into the function relationship.

[0057] In the third embodiment, the first maximum allowed output power of the charger can be obtained according to the real-time impedance of the bus capacitor and the real-time voltage of the bus capacitor, the second maximum allowed output power of the charger can be obtained according to the real-time impedance of the bus capacitor and the pre-obtained corresponding relationship between the bus capacitor impedance and the maximum output power, and the final maximum allowed output power for controlling the output power of the charger can be obtained according to the first maximum allowed output power and the second maximum allowed output power. For example, in some embodiments, the larger of the first maximum allowed output power and the second maximum allowed output power can be taken as the final maximum allowed output power; in other embodiments, the smaller of the first maximum allowed output power and the second maximum allowed output power can be taken as the final maximum allowed output power; in yet other embodiments, the average of the first maximum allowed output power and the second maximum allowed output power can be taken as the final maximum allowed output power.

[0058] Finally, it should be understood that the present application does not make any limitation on the specific implementation of step S300 of controlling the charger to output the maximum allowed output power as its output power. For more details on how to control the output power of the charger according to the target output power (i.e. the maximum allowed output power), please refer to the related technologies known to those skilled in the art, which will not be described in detail herein due to the limited space.

[0059] Next, the first embodiment described above will be described in detail.

[0060] Preferably, in some exemplary embodiments, the step S100 of obtaining the real-time impedance of the bus capacitor according to the AC current input to the first conversion circuit, the real-time duty cycle of the first conversion circuit, and the real-time voltage of the bus capacitor comprises:

[0061] S110: obtaining the ripple current effective value of the bus capacitor according to the AC current and the real-time duty cycle of the first conversion circuit;

[0062] S120: obtaining the ripple voltage effective value of the bus capacitor according to the real-time voltage of the bus capacitor;

[0063] S130: obtaining the impedance estimation value of the bus capacitor according to the ripple voltage effective value and the ripple current effective value.

[0064] Therefore, the present application lays a solid foundation for obtaining the impedance value of the bus capacitor by obtaining the ripple current effective value of the bus capacitor according to the AC current and the real-time duty cycle of the first conversion circuit, and obtaining the ripple voltage effective value of the bus capacitor according to the real-time voltage of the bus capacitor; and lays a good foundation for obtaining the maximum allowable output power of the charger by obtaining the impedance estimation value of the bus capacitor according to the ripple voltage effective value and the ripple current effective value.

[0065] It should be noted that the skilled in the art should understand that the present application does not make any limitation on the order of the steps S110 and S120. In some embodiments, the step S110 of obtaining the ripple current effective value of the bus capacitor can be performed first, and then the step S120 of obtaining the ripple voltage effective value of the bus capacitor can be performed; in other embodiments, the step S120 of obtaining the ripple voltage effective value of the bus capacitor can be performed first, and then the step S110 of obtaining the ripple current effective value of the bus capacitor can be performed; in still other embodiments, the steps S110 and S120 can be performed simultaneously to obtain the ripple current effective value and the ripple voltage effective value of the bus capacitor, respectively.

[0066] Further, the step S130 of obtaining the impedance estimation value of the bus capacitor according to the ripple voltage effective value and the ripple current effective value specifically comprises: dividing the ripple voltage effective value by the ripple current effective value to obtain the impedance estimation value of the bus capacitor.

[0067] Preferably, in some exemplary embodiments, the step S110 of obtaining the ripple current effective value of the bus capacitor according to the AC current and the real-time duty cycle of the first conversion circuit comprises:

[0068] S111: obtaining a current estimation value of the bus capacitor according to the alternating current and a real-time duty cycle of the first conversion circuit.

[0069] Specifically, the product of the alternating current and the real-time duty cycle of the first conversion circuit can be taken as the current estimation value of the bus capacitor.

[0070] S112: performing 2 times frequency band-pass filtering of the alternating voltage on the current estimation value and obtaining a ripple current effective value of the bus capacitor according to the filtered current estimation value.

[0071] Therefore, by performing 2 times frequency band-pass filtering of the alternating voltage on the current estimation value and obtaining a ripple current effective value of the bus capacitor according to the filtered current estimation value, the reliability of the ripple current effective value can be effectively improved.

[0072] It should be understood by those skilled in the art that the specific implementation of the 2 times frequency band-pass filtering of the alternating voltage on the current estimation value is not limited. For example, the existing band-pass filter of the charger can be used to perform 2 times frequency band-pass filtering of the alternating voltage on the current estimation value.

[0073] It should be understood by those skilled in the art that the specific implementation of the ripple current effective value of the bus capacitor is also not limited. The above is only an exemplary description of the preferred embodiment. For example, in other embodiments, the ripple current calculation method based on the current waveform can also be used. For more details, please refer to the content related to the calculation of the effective value of the capacitor ripple current, which is well known to those skilled in the art.

[0074] Preferably, in some exemplary embodiments, step S120 obtains a ripple voltage effective value of the bus capacitor according to a real-time voltage of the bus capacitor, specifically comprising:

[0075] performing 2 times frequency band-pass filtering of the alternating voltage on the real-time voltage of the bus capacitor and obtaining a ripple voltage effective value of the bus capacitor according to the filtered real-time voltage.

[0076] Therefore, by performing 2 times frequency band-pass filtering of the alternating voltage on the real-time voltage of the bus capacitor and obtaining a ripple voltage effective value of the bus capacitor according to the filtered real-time voltage, the reliability of the ripple voltage effective value can be effectively improved.

[0077] It should be noted that the skilled in the art should understand that the specific implementation of the present application for the 2 times frequency band-pass filtering of the real-time voltage of the AC voltage is not limited. Exemplarily, the existing band-pass filter of the charger can be used to perform the 2 times frequency band-pass filtering of the real-time voltage of the AC voltage.

[0078] It should be further noted that the skilled in the art should understand that the specific implementation of the present application for the ripple voltage effective value of the bus capacitor is also not limited. The above is only an exemplary description of the preferred embodiment. For more details, please refer to the content related to the calculation of the ripple voltage effective value which is well known to the skilled in the art.

[0079] Exemplarily, please refer to Figure 3 , Figure 3 the principle diagram of a specific example for obtaining the real-time impedance of the bus capacitor of the present application. Figure 3 In the example, the frequency of the AC voltage is 50 Hz, from Figure 3 it can be seen that, on the one hand, the AC current I AC is first multiplied by the real-time duty cycle Duty of the first conversion circuit to obtain the current estimation value I Bus of the bus capacitor, then the current estimation value I Bus is band-pass filtered by a 100 Hz (2 times of the 50 Hz AC voltage) band-pass filter to obtain the filtered current estimation value I Bus_100Hz , and finally the 100 Hz (2 times of the 50 Hz AC voltage) current effective value calculation is performed according to the filtered current estimation value I Bus_100Hz to obtain the ripple current effective value I Bus_100Hz_RMS of the bus capacitor; on the other hand, the real-time voltage U Bus is first band-pass filtered by a 100 Hz (2 times of the 50 Hz AC voltage) band-pass filter to obtain the filtered real-time voltage U Bus_100Hz , then the 100 Hz (2 times of the 50 Hz AC voltage) voltage effective value calculation is performed on the filtered real-time voltage U Bus_100Hz to obtain the ripple voltage effective value U Bus_100Hz_RMS of the bus capacitor; finally, the real-time impedance (i.e. impedance estimation value) Z Bus_100Hz of the bus capacitor is obtained by dividing the ripple voltage effective value U Bus_100Hz_RMS by the ripple current effective value I Bus_100Hz_RMS .

[0080] Preferably, in some exemplary embodiments, the step S200 obtains the maximum allowed output power of the charger according to the real-time impedance of the bus capacitor and the real-time voltage of the bus capacitor, including:

[0081] S210: performing 2 times frequency notch filtering on the real-time voltage of the bus capacitor with alternating current voltage, and obtaining a direct current voltage component of the bus capacitor according to the direct current voltage component;

[0082] S220: obtaining the maximum allowed output power of the charger according to the real-time impedance of the bus capacitor, the direct current voltage component, and a preset peak value of the maximum allowed ripple voltage of the bus capacitor.

[0083] Therefore, the maximum allowed output power of the charger is obtained according to the real-time impedance of the bus capacitor, the direct current voltage component, and the preset peak value of the maximum allowed ripple voltage of the bus capacitor, which lays a good foundation for heating the bus capacitor with the maximum safe ripple, can significantly reduce the risk of damage to the bus capacitor caused by the over-high output power of the charger due to the calibration error, and can accelerate the low-temperature starting time and improve the user experience.

[0084] Preferably, in some exemplary embodiments, the step S220 of obtaining the maximum allowed output power of the charger according to the real-time impedance of the bus capacitor, the direct current voltage component, and the preset peak value of the maximum allowed ripple voltage of the bus capacitor comprises:

[0085] S221: taking the smaller one of the real-time impedance and the real-time impedance of the bus capacitor at the last time as the effective impedance of the bus capacitor; wherein the initial value of the real-time impedance at the last time is greater than or equal to 10Ω and less than or equal to 99Ω.

[0086] S222: obtaining the maximum allowed output power of the charger according to the effective impedance, the direct current voltage component, and the preset peak value of the maximum allowed ripple voltage of the bus capacitor.

[0087] Therefore, based on the basic rule that the temperature of the bus capacitor will only increase and will not decrease after the output power of the charger (that is, the impedance of the bus capacitor will only decrease and will not increase) under normal circumstances, by taking the smaller one of the real-time impedance and the real-time impedance of the bus capacitor at the last time as the effective impedance of the bus capacitor, the dithering of the calculated effective impedance can be effectively avoided, so that the output power of the charger is more stable.

[0088] Exemplarily, in some preferred embodiments, the initial value of the real-time impedance is 25Ω. It should be noted that those skilled in the art should understand that the initial value of the real-time impedance greater than or equal to 10Ω and less than or equal to 99Ω herein is only an exemplary description of the preferred embodiments, but not a limitation of the present application. The present application does not make any limitation on the specific value of the initial value of the real-time impedance, which should be reasonably set according to the actual needs when implementing the present application.

[0089] It can be understood that, when the minimum calculation is performed at the starting moment, since the real-time impedance of the bus capacitor at the previous moment has not been obtained, in this case, the initial value of the real-time impedance is used as the real-time impedance of the bus capacitor at the previous moment; then, the smaller one of the real-time impedance at the current moment and the real-time impedance of the bus capacitor at the previous moment is taken as the effective impedance of the bus capacitor.

[0090] Exemplarily, the maximum allowed output power of the charger can be calculated by the following formula (1) :

[0091]

[0092] In formula (1), MaxPower is the maximum allowed output power of the charger, U Bus_Dc is the DC voltage component, U Bus_MaxRipple is the maximum allowed ripple voltage preset peak value of the bus capacitor, Z Bus_100Hz_min is the smaller one of the real-time impedance and the real-time impedance of the bus capacitor at the previous moment.

[0093] Preferably, in some exemplary embodiments, the maximum allowed ripple voltage preset peak value is greater than or equal to 40V and less than or equal to 60V. Preferably, the maximum allowed ripple voltage preset peak value is 40V.

[0094] It should be understood by those skilled in the art that the maximum allowed ripple voltage preset peak value greater than or equal to 40V and less than or equal to 60V is only an exemplary description of a preferred embodiment, and is not a limitation of the present application. The present application does not make any limitation on the specific value of the maximum allowed ripple voltage preset peak value, which should be reasonably set according to actual needs when implementing the present application.

[0095] Exemplarily, please refer to Figure 4 , Figure 4 is a schematic diagram of a specific example for obtaining the maximum allowed output power of the present application. Figure 4 In the example, the frequency of the alternating voltage is 50Hz, from Figure 4 It can be seen that, in this example, on the one hand, the smaller one of the real-time impedance Z Bus_100Hz and the real-time impedance of the bus capacitor at the previous moment (the initial value is 25Ω, and the subsequent value is Z Bus_100Hz_min at the previous moment) is taken as the effective impedance Z Bus_100Hz_min of the bus capacitor; on the other hand, the real-time voltage U Bus is first subjected to notch filtering to obtain the DC voltage component U Bus_DCFinally, the peak value U is preset according to the maximum allowable ripple voltage Bus_MaxRipple , effective impedance Z Bus_100Hz_min And the DC voltage component U Bus_DC Get the maximum allowable output power MaxPower.

[0096] Another embodiment of the present invention provides a vehicle controller, for example, see Figure 5 , Figure 5 This is a block diagram of the vehicle controller provided in this embodiment. Figure 5 As shown, the vehicle controller provided in this embodiment includes a processor 210 and a memory 220. The memory 220 stores a computer program. When executed by the processor 210, the computer program implements the low-temperature startup control method for the charger charging mode provided in any of the above embodiments. Because the vehicle controller provided in this embodiment and the low-temperature startup control method for the charger charging mode provided in the present invention are based on the same inventive concept, the vehicle controller provided in this embodiment at least has all the advantages of the low-temperature startup control method for the charger charging mode provided in the present invention. For details, please refer to the above description of the beneficial effects of the low-temperature startup control method for the charger charging mode, and will not be repeated here.

[0097] For example, Figure 5 As shown, the vehicle controller may further include a communication interface 230 and a communication bus 240, wherein the processor 210, the communication interface 230, and the memory 220 communicate with each other via the communication bus 240. The communication bus 240 includes, but is not limited to, a CAN bus. For ease of illustration, the figure shows only one thick line, but this does not mean that there is only one bus or one type of bus. The communication interface 230 is used for communication between the vehicle controller (such as the charger controller) and other controllers (such as the vehicle controller, the autonomous driving domain controller, the battery management system, etc., not shown in the figure). The communication bus 240 connects the various dispersed nodes of the vehicle controller (such as the charger controller) and other controllers (such as the battery management system, etc., not shown in the figure) into a closed-loop system, enabling each controller to communicate and transmit data in multiple working states (parking state, charging state, starting state, running state, vehicle forward and reverse state, regenerative braking state, mechanical braking state, general fault state, major fault state), thereby realizing the vehicle control function.

[0098] The processor 210 in the present application can be a microcontroller unit (MCU), and can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or can also be any conventional processor, etc. The processor 210 is the control center of the vehicle controller, and connects various parts of the vehicle controller through various interfaces and lines.

[0099] The memory 220 can be used to store the computer program, and the processor 210 realizes various functions of the vehicle controller by running or executing the computer program stored in the memory 220 and calling the data stored in the memory 220.

[0100] The memory 220 can include non-volatile and / or volatile memory. The non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. The volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0101] Another embodiment of the present application provides a readable storage medium, wherein a computer program is stored in the readable storage medium, and the computer program can realize the low-temperature starting control method in the charger charging mode when executed by a processor. Since the readable storage medium provided by the present application and the low-temperature starting control method in the charger charging mode provided by the present application belong to the same inventive concept, the readable storage medium provided by the present application has at least all the advantages of the low-temperature starting control method in the charger charging mode provided by the present application. For the details of the beneficial effects of the readable storage medium provided by the present application, please refer to the related description of the beneficial effects of the low-temperature starting control method in the charger charging mode provided by the present application, which will not be repeated here.

[0102] The readable storage medium of the embodiments of the present application can adopt any combination of one or more computer-readable media. The readable medium can be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium may, for example, but is not limited to, an electrical, magnetic, optical, electromagnetic, infrared or semiconductor system, device or component, or any combination thereof. More specific examples (non-exhaustive list) of the computer-readable storage medium include an electrical connection having one or more wires, a portable computer hard disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this paper, the computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, device or component.

[0103] The computer-readable signal medium can include a data signal propagating in a baseband or as a part of a carrier wave propagating in a baseband, wherein the computer-readable program code is carried. Such a propagating data signal can take various forms, including but not limited to electromagnetic signals, optical signals or any suitable combination thereof. The computer-readable signal medium can also be any computer-readable medium other than the computer-readable storage medium, which can send, propagate or transmit a program for use by or in combination with an instruction execution system, device or component.

[0104] Computer program code for carrying out operations of the present application can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0105] Compared with the prior art, the low-temperature starting control method, the controller and the medium provided by the application have the following advantages:

[0106] The low-temperature starting control method of the charger provided by the application obtains the real-time impedance of the bus capacitor according to the alternating current input to the first conversion circuit, the real-time duty cycle of the first conversion circuit and the real-time voltage of the bus capacitor, and obtains the maximum allowable output power of the charger according to the real-time impedance of the bus capacitor, and the corresponding relationship between the real-time voltage of the bus capacitor and / or the pre-acquired impedance of the bus capacitor and the maximum output power, and finally controls the charger to take the maximum allowable output power as the output power of the charger. As can be seen, the application does not need to be calibrated, and only needs to obtain the maximum output power under the safe voltage of the bus capacitor according to the real-time state of the bus capacitor through the real-time impedance of the bus capacitor, so as to limit the output power of the charger. In this way, the application can heat the bus capacitor with the maximum safe ripple, which not only can significantly reduce the risk of damage to the bus capacitor caused by the over-high output power of the charger due to the calibration error, but also can speed up the low-temperature starting time and improve the user experience. At the same time, the logic of the application is simple and easy to implement.

[0107] It should be noted that the apparatus and method disclosed in the embodiments herein can also be implemented in other ways. The apparatus embodiments described above are merely exemplary, and the schematic flow chart and block diagram of the flow chart and block diagram show the possible architectural, functional and operational scenarios of the apparatus, method and computer program product according to the embodiments herein. In this regard, each block in the flow chart or block diagram can represent a module, a segment or a portion of code, which comprises one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions noted in the blocks can occur out of the order noted in the flow chart. For example, two blocks shown in succession can in fact be executed substantially concurrently or the blocks can sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block and combination of blocks in the flow chart and / or block diagram can be implemented by a dedicated hardware-based system that carries out the specified function or action, or a combination of dedicated hardware and computer instructions.

[0108] In addition, each functional module in the various embodiments herein can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0109] The above description is merely a description of the preferred embodiments of the low-temperature starting control method, controller and medium in the charging mode of the charging machine according to the present application, and is not intended to limit the scope of the present application. Any modification or modification made by a person skilled in the art based on the above disclosure is within the scope of the present application. Obviously, those skilled in the art can make various modifications and changes to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and changes are within the scope of the present application and its equivalent technology, the present application also intends to include these modifications and changes.

Claims

1. A low temperature start control method for a charger in charging mode, characterized in that: The charger includes a first conversion circuit for converting an AC voltage into a DC voltage, a bus capacitor, and a second conversion circuit for converting the DC voltage into a voltage range required by a load. The method includes: Obtaining a real-time impedance of the bus capacitor according to the AC current input to the first conversion circuit, the real-time duty cycle of the first conversion circuit, and the real-time voltage of the bus capacitor; Obtaining the maximum allowable output power of the charger according to the real-time impedance of the bus capacitor, the real-time voltage of the bus capacitor, and / or a pre-acquired correspondence between the bus capacitor impedance and the maximum output power; The charger is controlled to use the maximum allowable output power as its output power.

2. The low-temperature startup control method in the charger charging mode according to claim 1, characterized in that: The obtaining of the real-time impedance of the bus capacitor according to the AC current input to the first conversion circuit, the real-time duty cycle of the first conversion circuit, and the real-time voltage of the bus capacitor includes: Obtaining an effective value of a ripple current of the bus capacitor according to the AC current and a real-time duty cycle of the first conversion circuit; Obtaining an effective value of the ripple voltage of the bus capacitor according to the real-time voltage of the bus capacitor; An impedance estimation value of the bus capacitor is obtained according to the ripple voltage effective value and the ripple current effective value.

3. The low temperature start control method in the charger charging mode according to claim 2, characterized in that: Obtaining the effective value of the ripple current of the bus capacitor according to the AC current and the real-time duty cycle of the first conversion circuit includes: Obtaining an estimated current value of the bus capacitor according to the AC current and the real-time duty cycle of the first conversion circuit; The current estimation value is subjected to a band-pass filter at a frequency twice that of the AC voltage, and the effective value of the ripple current of the bus capacitor is obtained according to the filtered current estimation value.

4. The low temperature start control method in the charger charging mode according to claim 2, characterized in that: Obtaining the effective value of the ripple voltage of the bus capacitor according to the real-time voltage of the bus capacitor includes: The real-time voltage of the bus capacitor is subjected to a band-pass filter at a frequency twice that of the AC voltage, and the effective value of the ripple voltage of the bus capacitor is obtained according to the filtered real-time voltage.

5. The low temperature start control method in the charger charging mode according to claim 1, characterized in that: Obtaining the maximum allowable output power of the charger according to the real-time impedance of the bus capacitor and the real-time voltage of the bus capacitor includes: Performing a notch filter with a frequency twice that of the AC voltage on the real-time voltage of the bus capacitor and obtaining a DC voltage component of the bus capacitor according to the DC voltage component; The maximum allowable output power of the charger is obtained according to the real-time impedance of the bus capacitor, the DC voltage component, and a preset peak value of the maximum allowable ripple voltage of the bus capacitor.

6. The low temperature start control method in the charger charging mode according to claim 5, characterized in that: Obtaining the maximum allowable output power of the charger according to the real-time impedance of the bus capacitor, the DC voltage component, and a preset peak value of the maximum allowable ripple voltage of the bus capacitor includes: The smaller of the real-time impedance and the real-time impedance of the bus capacitor at the previous moment is used as the effective impedance of the bus capacitor; wherein the initial value of the real-time impedance at the previous moment is greater than or equal to 10Ω and less than or equal to 99Ω; The maximum allowable output power of the charger is obtained according to the effective impedance, the DC voltage component and the preset peak value of the maximum allowable ripple voltage of the bus capacitor.

7. The low temperature start control method in the charger charging mode according to claim 5, characterized in that: The maximum allowable ripple voltage preset peak value is greater than or equal to 40V and less than or equal to 60V.

8. The low temperature start control method in the charger charging mode according to claim 1, characterized in that: The corresponding relationship between the bus capacitance impedance and the maximum output power is obtained through calibration.

9. A vehicle controller, characterized in that: The device comprises a processor and a memory, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the low-temperature starting control method in the charger charging mode according to any one of claims 1 to 8 is implemented.

10. A readable storage medium, characterized in that: The readable storage medium stores a computer program, and when the computer program is executed by the processor, the low-temperature starting control method in the charging mode of the charger according to any one of claims 1 to 8 is implemented.

Images