Anti-condensation control method, controller and power converter

Abstract

The invention provides an anti-condensation control method, a controller and a power converter, and is applied to the technical field of power electronics. If it is determined that the target power device meets the preset condensation condition based on the current device temperature of the target power device and the current internal environment temperature, the temperature difference between the device temperature of the target power device and the internal environment temperature of the power converter is reduced, so that condensation at the target power device is avoided; the insulation performance of the target power device is ensured, and the safety of the power converter is improved.

Description

Technical Field

[0001] This application relates to the field of power electronics technology, specifically to an anti-condensation control method, controller, and power converter. Background Technology

[0002] Power converters typically contain multiple power devices. Taking an inverter as an example, an inverter internally includes an inverter circuit and multiple boost circuits. The input side of each boost circuit is connected to a DC power source such as a photovoltaic module, while its output side is connected to the DC side of the inverter circuit. The AC side of the inverter circuit is connected to the power grid. Each boost circuit contains a power device. In practical applications, due to the varying actual output power of photovoltaic modules, some boost circuits may operate in a non-operating or low-load state for extended periods. This can lead to condensation at the power devices, reducing their insulation performance and potentially causing short circuits, device failure, and even affecting the overall safe operation of the power converter. Summary of the Invention

[0003] In view of this, this application aims to provide an anti-condensation control method, controller and power converter to solve the problem in the related art that power devices are prone to condensation, which reduces the insulation performance of power devices and affects the safe operation of power converters.

[0004] In a first aspect, this application provides a method for preventing condensation control, comprising: The current device temperature of the target power device in the power converter and the current internal ambient temperature of the power converter are obtained, wherein the power converter includes multiple power devices, and the target power device is any one of the multiple power devices; If the target power device is determined to meet the preset condensation conditions based on the current device temperature and the current internal ambient temperature, then the temperature difference between the device temperature of the target power device and the internal ambient temperature of the power converter is reduced.

[0005] In a second aspect, this application provides a controller, including a memory, a processor, and a computer program stored in the memory and executed by the processor, wherein the processor executes the computer program to implement the steps of the anti-condensation control method provided in any embodiment of the first aspect of this application.

[0006] Thirdly, this application provides a power converter, comprising: a plurality of power devices, a first temperature detector, a second temperature detector, and a controller, wherein, The first temperature detector is configured to detect the device temperature of the power device; The second temperature detector is configured to detect the internal ambient temperature of the power converter; The controller is connected to the first temperature detector and the second temperature detector respectively, and the controller is configured to perform the steps of the anti-condensation control method as described in any embodiment of the first aspect of this application to perform anti-condensation control on the power device.

[0007] Based on the above, the anti-condensation control method provided in this application is applied to a power converter. After obtaining the current device temperature of the target power device and the current internal ambient temperature of the power converter, if it is determined that the target power device meets the preset condensation conditions based on the current device temperature and the current internal ambient temperature, the temperature difference between the device temperature of the target power device and the internal ambient temperature of the power converter is reduced, thereby avoiding condensation at the target power device, ensuring the insulation performance of the target power device, and improving the safety of the power converter. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0009] Figure 1 This is a flowchart of the first anti-condensation control method provided in the embodiments of this application.

[0010] Figure 2 This is a flowchart of the second anti-condensation control method provided in the embodiments of this application.

[0011] Figure 3 This is a flowchart of the third anti-condensation control method provided in the embodiments of this application.

[0012] Figure 4 This is a flowchart of the fourth anti-condensation control method provided in the embodiments of this application.

[0013] Figure 5 This is a flowchart of the fifth anti-condensation control method provided in the embodiments of this application.

[0014] Figure 6 This is a flowchart of the sixth anti-condensation control method provided in the embodiments of this application.

[0015] Figure 7 This is a flowchart of the seventh anti-condensation control method provided in the embodiments of this application.

[0016] Figure 8 This is a schematic diagram showing the location of the heater inside the power converter in related technologies.

[0017] Figure 9 This is a flowchart of the eighth anti-condensation control method provided in the embodiments of this application.

[0018] Figure 10 This is a flowchart of the ninth anti-condensation control method provided in the embodiments of this application.

[0019] Figure 11 This is a flowchart of the tenth anti-condensation control method provided in the embodiments of this application.

[0020] Figure 12 This is a flowchart of the eleventh anti-condensation control method provided in the embodiments of this application.

[0021] Figure 13 This is a structural block diagram of a controller provided in an embodiment of this application. Detailed Implementation

[0022] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0023] To address the problem of condensation occurring when power devices in power converters are inactive or operating at low load for extended periods in practical applications, leading to reduced insulation performance and impacting the safe operation of the power converter, this application provides an anti-condensation control method. Based on the current device temperature and the current internal ambient temperature of the power converter, if the power device meets preset condensation conditions, the method reduces the temperature difference between the device temperature and the internal ambient temperature of the power converter. This prevents condensation at the power device, ensures its insulation performance, and improves the safety of the power converter.

[0024] The anti-condensation control methods provided in the various embodiments of this application can be executed by a controller. The controller can be a controller in a power converter used to control the operation of the original circuit, or it can be a newly added controller specifically for executing the anti-condensation control methods provided in this application. Of course, in some cases, a network-side controller can also be selected. No specific restrictions are made here.

[0025] See Figure 1 As shown in the embodiments of this application, the anti-condensation control method includes the following steps.

[0026] S100: Obtain the current device temperature of the target power device in the power converter and the current internal ambient temperature of the power converter.

[0027] In practical applications, a power converter is equipped with a device housing and multiple power devices disposed inside the device housing. These power devices may belong to the same power circuit or different power circuits. The internal space of the device housing is the internal environment of the power converter. This definition is used in the embodiments of this application and subsequent embodiments, and will not be repeated in the following content.

[0028] It is understandable that power devices in a power converter will generate losses during operation, and these losses will be dissipated in the form of heat. This will not only cause the temperature of the power devices themselves to rise, i.e., the device temperature, but also cause the temperature of the internal environment of the power converter to rise. For the sake of describing the anti-condensation control method provided in the various embodiments of this application, the temperature of the internal space of the power converter is defined as the internal environment temperature.

[0029] As mentioned earlier, in the actual application of power converters, some power devices may not work or operate under low load, which may lead to condensation on the power devices. The inventors have found that the excessive temperature difference between the power device temperature and the internal ambient temperature of the power converter, and the device temperature being lower than the condensation point temperature, is the key reason for condensation on the power devices. Based on this, it is first necessary to obtain the current device temperature of the power devices in the power converter and the current internal ambient temperature of the power converter.

[0030] In one alternative implementation, a temperature sensor can be installed inside the device housing to collect the device temperature and the internal ambient temperature. It is understood that, in practical applications, while meeting safety regulations, the temperature sensor used to collect the device temperature should be as close as possible to the power device to improve the accuracy of the temperature sampling results. As for collecting the internal ambient temperature, temperature sensors can be placed at different locations within the power converter's internal space, and the average value of the collected values ​​can be used as the internal ambient temperature. Of course, other methods can also be used to determine the internal ambient temperature, which will not be detailed here.

[0031] S110. Determine whether the target power device meets the preset condensation conditions based on the current device temperature and the current internal ambient temperature. If so, execute S120.

[0032] As mentioned earlier, a large temperature difference between the power device's temperature and the power converter's internal ambient temperature is a key cause of condensation on the power device. Therefore, it's possible to determine whether a power device meets preset condensation conditions based on the temperature difference between its current device temperature and the current internal ambient temperature. Specifically, anti-condensation measures can be implemented for one or more power devices. Taking one power device as an example, referred to as the target power device, the temperature difference between its current device temperature and the current internal ambient temperature can be calculated. If this temperature difference is greater than a first preset temperature threshold, the target power device is considered to meet the preset condensation conditions. The first preset temperature threshold can be set based on historical data of the power converter's internal ambient temperature and device temperature, safety requirements for condensation control, and other relevant factors. This application does not limit the specific value of the first preset temperature threshold. It is understood that in practical applications, the target power device's temperature may be lower than the internal ambient temperature, while condensation is unlikely to occur if the device temperature is higher than the internal ambient temperature.

[0033] In another optional implementation, the power converter is also equipped with a humidity sensor, which can collect the humidity value of the internal environment of the power converter. Based on this, in addition to obtaining the current device temperature and the current internal ambient temperature, the current internal ambient humidity of the power converter collected by the humidity sensor is further obtained. Based on the obtained current internal ambient humidity and current internal ambient temperature, the dew point temperature is determined. It can be understood that this dew point temperature is the temperature at which condensation occurs on the power device. Specifically, the dew point temperature can be calculated with reference to the following formula: (1) Where T1 represents the dew point temperature; T2 represents the current internal ambient temperature; A1 represents the current internal humidity.

[0034] After determining the dew point temperature, the temperature difference between the current device temperature and the dew point temperature of the target power device can be calculated. If the obtained temperature difference is less than or equal to a second preset temperature threshold, it can be determined that the target power device meets the preset condensation condition. The second preset temperature threshold can be set based on historical data of device temperatures and dew point temperatures in the power converter, and this application does not limit the specific value of the second preset temperature threshold. It is understood that in practical applications, condensation will occur on the target power device when the current device temperature is less than or equal to the dew point temperature. In other words, condensation can be avoided only when the current device temperature of the target power device is greater than the dew point temperature. Therefore, as an implementation method, the result of subtracting the dew point temperature from the current device temperature of the target power device should be used as the temperature difference between the current device temperature and the dew point temperature.

[0035] It should be noted that if the target power device is determined not to meet the preset condensation conditions after the aforementioned steps, the current control cycle can be exited and subsequent steps will not be executed.

[0036] S120, reduce the temperature difference between the target power device temperature and the internal ambient temperature of the power converter.

[0037] If the target power device meets the preset condensation conditions, condensation can be prevented by reducing the temperature difference between the target power device's temperature and the internal ambient temperature of the power converter. Specifically, at least one of the following control measures can be used for condensation control: increasing the target power device's temperature or decreasing the power converter's internal ambient temperature. This means either increasing the device temperature alone or decreasing the internal ambient temperature alone, or increasing the device temperature while simultaneously decreasing the internal ambient temperature. All three control measures provided in this embodiment can achieve the goal of reducing the temperature difference between the device temperature and the internal ambient temperature.

[0038] In practical applications, at least one of the following heating measures can be used to raise the device temperature: increasing the loss of the target power device, reducing the heat dissipation efficiency of the target power device, and activating the heater to heat the target power device. Correspondingly, at least one of the following cooling measures can be used to lower the internal ambient temperature: improving the heat dissipation efficiency of the power converter's internal environment, reducing the overall power of the power converter, and reducing the rate of increase of the overall power. The specific execution processes of each heating and cooling measure will be detailed later and will not be elaborated here. It should be noted that both heating and cooling measures can be used independently or in combination as needed; any combination that achieves the goal of reducing the temperature difference between the device and the internal ambient temperature is acceptable.

[0039] In summary, the anti-condensation control method provided in this application, when determining that the target power device meets the preset condensation conditions based on the current device temperature of the target power device and the current internal ambient temperature of the power converter, reduces the temperature difference between the device temperature of the target power device and the internal ambient temperature of the power converter, ensuring that the device temperature is above the condensation point temperature, thereby avoiding condensation at the target power device, ensuring the insulation performance of the target power device, and improving the safety of the power converter.

[0040] As the foregoing has shown, raising the device temperature and lowering the internal ambient temperature may affect the normal operation of the power converter. To minimize the impact of condensation control, a corresponding exit mechanism should be provided. Therefore, this application provides another anti-condensation control method, see [link to relevant documentation]. Figure 2 As shown, the anti-condensation control method provided in this embodiment also includes the following steps.

[0041] S130. Determine whether the preset exit conditions are met. If yes, execute S140. If no, return to execute S120.

[0042] While reducing the temperature difference between the target power device and the internal ambient temperature of the power converter according to S120, it monitors whether the power converter meets the preset exit conditions. If the preset exit conditions are met, proceed to S140. Conversely, if the power converter does not meet the preset exit conditions, continue executing S120 to continuously shorten the temperature difference between the device temperature and the internal ambient temperature. The specific content of the preset exit conditions will be described in detail in subsequent sections with reference to specific embodiments, and will not be elaborated here.

[0043] S140. Control the power converter to operate according to the initial operating parameters.

[0044] In this embodiment, the initial operating parameters include the operating parameters of the power converter before reducing the temperature difference between the target power device temperature and the internal ambient temperature of the power converter according to S120. Of course, the initial operating parameters can also be understood as the operating parameters of the power converter before executing the anti-condensation control method provided in this application.

[0045] If the preset exit conditions are met, the power converter will be controlled to operate according to the initial operating parameters, thereby exiting the anti-condensation control process and restoring the normal operation of the power converter.

[0046] In summary, the anti-condensation control method provided in this embodiment, based on the aforementioned embodiments, provides an exit mechanism for the anti-condensation control process. Under the condition of meeting the preset exit conditions, the normal operation of the power converter is restored in a timely manner, minimizing the impact of the anti-condensation control process on the operation of the power converter, while also ensuring the operational safety of the power converter.

[0047] As mentioned above, the various heating and cooling measures provided in this application can be used independently or in combination. The following are some typical methods for preventing condensation control, in conjunction with specific embodiments.

[0048] First, the anti-condensation control method, which increases the device temperature by increasing the loss of the target power device, may include the following specific execution process: Figure 3 The following steps are shown. It should be noted that the anti-condensation control method provided in this embodiment is applicable to situations where the power converter does not have a humidity sensor. Of course, even if the power converter has a humidity sensor, but the humidity information it provides does not participate in condensation control, the anti-condensation control method provided in this embodiment can still be used.

[0049] S200: Obtain the current device temperature of the target power device and the current internal ambient temperature of the power converter.

[0050] In one optional implementation, the specific execution process of S200 can be referred to Figure 1 The details of S100 in the illustrated embodiment will not be repeated here.

[0051] S210. Determine whether the temperature difference between the current internal ambient temperature and the current device temperature of the target power device is greater than the first preset temperature threshold. If so, execute S220.

[0052] As mentioned earlier, a large temperature difference between the device temperature of the power device and the internal ambient temperature of the power converter is a key cause of condensation on the power device. Based on this, this step calculates the temperature difference between the current device temperature and the current internal ambient temperature of the target power device. If the temperature difference between the current device temperature and the current internal ambient temperature is greater than the first preset temperature threshold, it can be determined that the target power device meets the preset condensation condition, and then the subsequent S220 is executed. Conversely, if the temperature difference between the current device temperature and the current internal ambient temperature is less than or equal to the first preset temperature threshold, it is determined that the target power device does not meet the preset condensation condition, and the current control flow can be exited.

[0053] S220, Increase the loss of the target power device.

[0054] Given that the target power device meets the preset condensation conditions, this embodiment increases the device temperature of the target power device by increasing the heating measures that increase the loss of the target power device.

[0055] It is understandable that current flows through a power device only when it is in the conducting state, and losses are generated based on its own impedance. Moreover, the losses of a power device increase with the increase of the conduction time. Based on this, when the impedance of the target power device remains stable, the losses of the target power device can be increased by at least one of the following two methods: increasing the duty cycle of the control signal of the target power device and increasing the signal frequency of the control signal of the target power device.

[0056] Understandably, in practical applications, the conduction state of the target power device in the power converter is controlled by a control signal. For example, the control signal is a pulse signal. During the high-level phase of the pulse signal, the target power device is turned on, and correspondingly, during the low-level phase of the pulse signal, the target power device is turned off. In this case, the conduction time of the target power device can be increased by increasing the duty cycle of the control signal, thereby increasing the loss of the target power device and raising the device temperature.

[0057] As another alternative implementation, the signal frequency of the control signal can be increased while keeping the duty cycle of the control signal constant. It is understood that, under the same duration and duty cycle, the higher the signal frequency of the control signal, the longer the target power device will be in the conducting state within that duration. Therefore, the loss of the target power device can be increased by increasing the signal frequency of the control signal, thereby increasing the device temperature of the target power device.

[0058] S230. Determine whether the preset exit conditions are met. If yes, execute S240. If no, return to execute S220.

[0059] As the power device's losses increase, it generates more and more heat, and the device temperature will rise accordingly. If the temperature difference between the device and the internal ambient temperature is small enough, the possibility of condensation on the power device is extremely low. Based on this, as an optional preset exit condition, if the temperature difference between the target power device and the internal ambient temperature is less than a seventh preset temperature threshold, the preset exit condition is determined to be met, and S240 continues to be executed. Conversely, if the temperature difference between the target power device and the internal ambient temperature is greater than or equal to the seventh preset temperature threshold, the preset exit condition is determined not to be met, and S220 is returned to be executed to continuously reduce the temperature difference between the device and the internal ambient temperature. It should be emphasized that the anti-condensation control method provided in the various embodiments of this application addresses the problem of condensation caused by the power device's temperature being lower than the internal ambient temperature due to the device not working or operating under low load. The situation where the power device's temperature is higher than the internal ambient temperature is not considered in this application. As for the specific value of the seventh preset temperature threshold, in practical applications, it can be set in combination with specific control requirements, historical temperature difference data that causes condensation in power devices, design parameters of power converters, application scenarios, and other factors. This application does not limit the specific value of the seventh preset temperature threshold.

[0060] It should be noted that the aforementioned first preset temperature threshold is used to determine whether to increase the loss of the target power device, that is, to start raising the device temperature. The seventh preset temperature threshold mentioned in this embodiment is used to determine whether the preset exit condition is met and to restore the normal operation of the power converter. It can be seen that the first preset temperature threshold and the seventh preset temperature threshold can be equal or unequal. Considering that if the first preset temperature threshold and the seventh preset temperature threshold are equal, it is easy to cause frequent switching between the anti-condensation control process and the control process during normal operation of the power converter. Generally, the first preset temperature threshold will be greater than the seventh preset temperature threshold, and both the first preset temperature threshold and the seventh preset temperature threshold are greater than zero.

[0061] Furthermore, it is understandable that as the losses of power devices increase, their temperatures will rise, potentially reaching their maximum operating temperature. This triggers the power converter's preset protection mechanism, reducing its output power and causing overall power loss. To avoid this, while increasing the losses of the target power device as described above, the temperature difference between the device and the maximum operating temperature can be detected. When the temperature difference is less than a preset device temperature difference threshold, the preset exit condition is met, and subsequent steps are executed. To prevent the power converter from reducing its output power, the preset device temperature difference threshold should be greater than zero. The specific value of the preset device temperature difference threshold can be determined by considering factors such as the maximum operating temperature of the target power device, the relationship between the power converter's output power and operating temperature, and specific control requirements. This application does not limit the specific value of the preset device temperature difference threshold.

[0062] It should be noted that the above content provides two optional preset exit conditions. In practical applications, the two are related by OR, that is, as long as either one is met, it can be determined that the preset exit condition is met, and then the subsequent S240 is executed.

[0063] S240. Control the power converter to operate according to the initial operating parameters.

[0064] In an optional implementation, the specific execution process of S240 can be referred to Figure 2 The details of S140 in the illustrated embodiment will not be repeated here.

[0065] In summary, the anti-condensation control method provided in this embodiment utilizes the self-loss of the target power device during operation to increase the device temperature. This not only reduces the temperature difference between the device temperature and the internal ambient temperature, ensuring that the device temperature is above the condensation point temperature and preventing condensation at the target power device, thus guaranteeing the insulation performance of the target power device, but also features a simple control process that is easy to implement.

[0066] This application provides another method for preventing condensation control, applied to a power converter equipped with a humidity sensor. See [link to relevant documentation]. Figure 4 As shown, the anti-condensation control method provided in this embodiment includes the following steps.

[0067] S300: Obtain the current device temperature of the target power device, the current internal ambient temperature of the power converter, and the current internal ambient humidity.

[0068] In this embodiment, the power converter is also equipped with a humidity sensor, which can collect the current internal humidity of the power converter. Based on this, in addition to obtaining the current device temperature and the current internal ambient temperature, the current internal humidity of the power converter's internal space collected by the humidity sensor is further obtained. Of course, in practical applications, other methods can also be used to obtain the current internal humidity of the power converter's internal space, which will not be detailed here. The current device temperature and the current internal ambient temperature can be referred to... Figure 1 The details of S100 in the illustrated embodiment will not be repeated here.

[0069] S310. Determine the condensation point temperature based on the current internal ambient temperature and humidity.

[0070] In one alternative implementation, the dew point temperature can be calculated with reference to the aforementioned formula (1), which will not be repeated here.

[0071] S320. Determine whether the temperature difference between the current device temperature and the dew point temperature of the target power device is less than or equal to the second preset temperature threshold. If so, execute S330.

[0072] Calculate the temperature difference between the current device temperature and the dew point temperature of the target power device. If the resulting temperature difference is less than or equal to a second preset temperature threshold, then the target power device meets the preset condensation condition. It is understood that in practical applications, condensation will occur on the target power device when its current device temperature is less than or equal to the dew point temperature. In other words, condensation can only be avoided if the current device temperature is greater than the dew point temperature. Therefore, the temperature difference between the current device temperature and the dew point temperature should be calculated as the difference between the current device temperature and the dew point temperature.

[0073] If the temperature difference between the current device temperature and the dew point temperature of the target power device is less than or equal to the second preset temperature threshold, then S330 is executed. Conversely, if the temperature difference between the current device temperature and the dew point temperature of the target power device is greater than the second preset temperature threshold, it indicates that the target power device does not currently meet the preset condensation conditions, and the current control flow can be exited without executing subsequent steps.

[0074] S330, Increase the loss of the target power device.

[0075] In an optional implementation, the specific execution process of S330 can be referred to Figure 3 The details of S220 in the illustrated embodiment will not be repeated here.

[0076] S340. Determine whether the preset exit conditions are met. If yes, execute S350. If no, return to execute S330.

[0077] Based on the fundamental principle of condensation, condensation will occur on power devices when the device temperature is below the condensation point temperature, and conversely, condensation will not occur when the device temperature is above the condensation point temperature. Therefore, in one optional implementation, if the device temperature of the target power device is higher than the condensation point temperature obtained in the preceding steps, and the temperature difference between the target power device temperature and the condensation point temperature is greater than an eighth preset temperature threshold, then the preset exit condition can be determined to be met. As for the specific value of the eighth preset temperature threshold, in practical applications, it can be set based on specific control requirements, historical temperature difference data that leads to condensation on the target power device, as well as the design parameters of the power converter and the application scenario, among other factors. This application does not limit the specific value of the eighth preset temperature threshold.

[0078] It should be noted that the aforementioned second preset temperature threshold is used to determine whether to increase the loss of the target power device, that is, to start raising the device temperature. The eighth preset temperature threshold mentioned in this embodiment is used to determine whether the preset exit condition is met and to restore the normal operation of the power converter. It can be seen that the second preset temperature threshold and the eighth preset temperature threshold can be equal or unequal. Considering that if the second preset temperature threshold and the eighth preset temperature threshold are equal, it is easy to cause frequent switching between the anti-condensation control process and the control process during normal operation of the power converter. Generally, the second preset temperature threshold will be less than the eighth preset temperature threshold, and both the second preset temperature threshold and the eighth preset temperature threshold are greater than zero.

[0079] As mentioned earlier, as the power device's losses increase, its temperature will rise, potentially reaching its maximum operating temperature. This triggers the power converter's preset protection mechanism, reducing its output power. To avoid this, while increasing the target power device's losses according to the aforementioned steps, the temperature difference between the device temperature and the maximum operating temperature can be monitored. When the following conditions are met simultaneously, the preset exit condition is confirmed: Condition 1: The temperature difference between the device temperature and the maximum operating temperature is less than the preset device temperature difference threshold; Condition 2: The device temperature is higher than the dew point temperature, and the temperature difference between the device temperature and the dew point temperature is greater than the ninth preset temperature threshold. In case one, the device temperature is close to its maximum operating temperature. Further increasing the loss of the target power device could cause it to reach its maximum operating temperature, triggering the power converter's preset protection mechanism and resulting in power loss. In case two, the device temperature is not only higher than the dew point temperature but also has a certain difference between them. This condition indicates that the target power device will not experience condensation. When all the above conditions are met, it means the target power device will not experience condensation and its temperature is close to its maximum operating temperature. Further increasing the temperature will lead to power loss. Therefore, it is necessary to stop increasing the loss of the target power device and restore the power converter's normal operation, i.e., execute the subsequent step S350. The specific value of the preset device temperature difference threshold can be found in the relevant content of the aforementioned embodiments and will not be detailed here.

[0080] It should be noted that in actual use, there may be scenarios where both Situation 1 and Situation 2 cannot be met simultaneously. When Situation 1 is met but Situation 2 is not, this scenario does not meet the preset exit condition, and the losses of the target power device continue to increase. This may cause the device temperature to reach or even exceed the maximum operating temperature, thereby triggering the preset protection mechanism. It is understandable that compared to the loss caused by condensation leading to a complete machine failure, the loss caused by continuously increasing the device temperature and thus reducing the output power of the power converter is much smaller. Accordingly, when Situation 2 is met but Situation 1 is not, the device temperature is continuously increased until both Situation 1 and Situation 2 are met simultaneously. In this way, the temperature of the target power device is increased as much as possible without triggering the preset protection mechanism, thereby reducing the risk of condensation.

[0081] It should be noted that the above content provides two optional preset exit conditions. In practical applications, the two are related by OR, that is, as long as either one is met, it can be determined that the preset exit condition is met, and then the subsequent S350 is executed.

[0082] S350: Control the power converter to operate according to the initial operating parameters.

[0083] In an optional implementation, the specific execution process of S350 can be referred to Figure 2 The details of S140 in the illustrated embodiment will not be repeated here.

[0084] In summary, the anti-condensation control method provided in this embodiment utilizes the self-loss of the target power device during operation to increase the device temperature, thereby reducing the temperature difference between the device temperature and the internal ambient temperature. This ensures that the device temperature is above the condensation point temperature, preventing condensation at the target power device and guaranteeing its insulation performance. Furthermore, a robust exit mechanism is provided. By setting preset exit conditions, the reliable execution of the anti-condensation control process can be effectively ensured, improving the safety of the power converter.

[0085] This application also provides another anti-condensation control method, which reduces the temperature difference between the device temperature and the internal ambient temperature by reducing the heat dissipation efficiency of the target power device and improving the heat dissipation efficiency of the internal space of the power converter. The specific execution process may include, for example: Figure 5 The following steps are shown.

[0086] S400: Obtain the current device temperature of the target power device and the current internal ambient temperature of the power converter.

[0087] In an optional implementation, the specific execution process of S400 can be referred to Figure 1 The details of S100 in the illustrated embodiment will not be repeated here.

[0088] S410. Determine whether the temperature difference between the current internal ambient temperature and the current device temperature of the target power device is greater than the first preset temperature threshold. If so, execute S420.

[0089] In an optional implementation, the specific execution process of S410 can be referred to Figure 3 The details of S210 in the illustrated embodiment will not be repeated here.

[0090] S420 reduces the heat dissipation efficiency of the target power device and improves the heat dissipation efficiency of the internal space of the power converter.

[0091] In practical applications, power converters are equipped with heat dissipation devices at different locations within their internal space to regulate the internal temperature. Correspondingly, for power devices that generate a large amount of heat, separate heat dissipation devices are also configured for the power devices, provided that safety requirements are met, in order to more effectively regulate the device temperature.

[0092] Understandably, under constant load, the specific values ​​of device temperature and internal ambient temperature are directly related to the heat dissipation efficiency of the heat dissipation equipment. Reducing heat dissipation efficiency will increase device temperature and internal ambient temperature, while increasing heat dissipation efficiency will decrease device temperature and internal ambient temperature.

[0093] Based on the above, in one optional embodiment, the aforementioned heat dissipation device includes air-cooled heat dissipation devices, such as fans. In this case, the airflow speed of the air-cooled heat dissipation device corresponding to the target power device can be reduced until the air-cooled heat dissipation device is shut down. Alternatively, the airflow direction of the air-cooled heat dissipation device corresponding to the target power device can be adjusted to a direction away from the target power device, that is, the airflow of the air-cooled heat dissipation device is controlled to no longer blow towards the target power device. This can also reduce the heat dissipation efficiency of the air-cooled heat dissipation device for the target power device. In another optional embodiment, the aforementioned heat dissipation device includes liquid-cooled heat dissipation devices. In this case, the coolant flow rate of the liquid-cooled heat dissipation device corresponding to the target power device can be reduced until the liquid-cooled heat dissipation device is shut down. Of course, when the heat dissipation device corresponding to the target power device includes both air-cooled heat dissipation devices and liquid-cooled heat dissipation devices, the airflow speed (or airflow direction) of the air-cooled heat dissipation device and the coolant flow rate of the liquid-cooled heat dissipation device can be reduced simultaneously to reduce the heat dissipation efficiency of the target power device as quickly as possible. It is understood that as the heat dissipation efficiency decreases, the device temperature of the target power device will continue to rise.

[0094] Furthermore, to improve the heat dissipation efficiency of the power converter's internal space, as mentioned earlier, heat dissipation devices are installed at different locations within the power converter. Based on this, the heat dissipation efficiency of other heat dissipation devices besides those corresponding to the target power device can be improved, thereby increasing the heat dissipation efficiency of the power converter's internal space. In practical applications, the other heat dissipation devices mentioned here include not only those arranged within the power converter's internal space but also those arranged outside the power converter. This is because improving the heat dissipation efficiency of the external heat dissipation devices can improve the heat dissipation effect of the device casing, thus helping to reduce the heat dissipation effect of the internal space and consequently lowering the internal ambient temperature. Referring to the heat dissipation device configuration of the power device, the heat dissipation devices used to improve the heat dissipation efficiency of the power converter's internal space include at least one of air-cooled and liquid-cooled heat dissipation devices. In practical applications, increasing the airflow rate of the air-cooled heat dissipation device and the coolant flow rate of the liquid-cooled heat dissipation device is sufficient, and will not be elaborated further here.

[0095] It should be noted that simply reducing the heat dissipation efficiency of power devices or simply increasing the heat dissipation efficiency of the internal space of the power converter can also achieve the purpose of reducing the temperature difference between the device temperature and the internal ambient temperature. This is also within the scope of protection of this application. In practical applications, different control schemes can be selected according to the actual condensation control requirements.

[0096] S430. Determine whether the preset exit conditions are met. If yes, execute S440. If no, return to execute S420.

[0097] It is understandable that reducing the heat dissipation efficiency of power devices can increase their device temperature, and improving the heat dissipation efficiency of the internal space of the power converter can reduce the internal ambient temperature. Based on this, as an optional implementation method, the specific execution process of S430 can be referred to Figure 3 The details of S230 in the illustrated embodiment will not be repeated here.

[0098] S440: Control the power converter to operate according to the initial operating parameters.

[0099] In an optional implementation, the specific execution process of S440 can be referred to Figure 2 The details of S140 in the illustrated embodiment will not be repeated here. It should be noted that the anti-condensation control method provided in this embodiment, which reduces the temperature difference between the device and the internal environment, mainly relies on the control of the operation of the heat dissipation equipment. Therefore, controlling the power converter to run according to the initial operating parameters mainly refers to restoring the operating parameters of the heat dissipation equipment before the execution of S420.

[0100] In summary, the anti-condensation control method provided in this embodiment increases the device temperature of the target power device by reducing its heat dissipation efficiency, and decreases the internal ambient temperature by increasing the heat dissipation efficiency of the internal space of the power converter. This effectively reduces the temperature difference between the device temperature of the target power device and the internal ambient temperature, thereby preventing condensation at the target power device, ensuring the insulation performance of the target power device, and improving the safety of the power converter.

[0101] This application provides another anti-condensation control method applied to a power converter equipped with a humidity sensor. It similarly prevents condensation on the target power device by adjusting the heat dissipation efficiency of the target power device and the internal space of the power converter. See [link to relevant documentation]. Figure 6 As shown, the anti-condensation control method provided in this embodiment includes the following steps.

[0102] S500: Obtain the current device temperature of the target power device, the current internal ambient temperature of the power converter, and the current internal ambient humidity.

[0103] In an optional implementation, the specific execution process of S500 can be referred to Figure 4 The details of S300 in the illustrated embodiment will not be repeated here.

[0104] S510. Determine the condensation point temperature based on the current internal ambient temperature and humidity.

[0105] In one alternative implementation, the dew point temperature can be calculated with reference to the aforementioned formula (1), which will not be repeated here.

[0106] S520. Determine whether the temperature difference between the current device temperature and the dew point temperature of the target power device is less than or equal to the second preset temperature threshold. If so, execute S530.

[0107] Calculate the temperature difference between the current device temperature and the dew point temperature of the target power device. If the temperature difference is less than or equal to a second preset temperature threshold, the target power device is deemed to meet the preset condensation condition. It is understood that in practical applications, condensation will occur on the target power device when its current device temperature is less than or equal to the dew point temperature. In other words, condensation can only be avoided if the current device temperature is greater than the dew point temperature. Therefore, the temperature difference between the current device temperature and the dew point temperature should be calculated as the difference between the current device temperature and the dew point temperature.

[0108] If the temperature difference between the current device temperature and the dew point temperature is less than or equal to the second preset temperature threshold, then S530 is executed. Conversely, if the temperature difference between the current device temperature and the dew point temperature is greater than the second preset temperature threshold, it indicates that the target power device does not currently meet the preset condensation conditions, and the current control flow can be exited without executing subsequent steps.

[0109] S530 reduces the heat dissipation efficiency of the target power device and improves the heat dissipation efficiency of the internal space of the power converter.

[0110] In an optional implementation, the specific execution process of S530 can be referred to Figure 5 The details of S420 in the illustrated embodiment will not be repeated here.

[0111] S540. Determine whether the preset exit conditions are met. If yes, execute S550. If no, return to execute S530.

[0112] It is understandable that reducing the heat dissipation efficiency of power devices can increase their device temperature. Improving the heat dissipation efficiency of the internal space of the power converter can reduce the internal ambient temperature. Therefore, in one optional implementation, if the device temperature of the target power device is higher than the dew point temperature obtained in the aforementioned steps, and the temperature difference between the device temperature and the dew point temperature is greater than an eighth preset temperature threshold, then the preset exit condition can be determined to be met. In another optional implementation, when the device temperature of the target power device meets the target condition, the preset exit condition can also be determined to be met. The target condition includes: the temperature difference between the device temperature of the target power device and the maximum operating temperature is less than a preset device temperature difference threshold; and the temperature difference between the device temperature of the target power device and the dew point temperature is greater than a ninth preset temperature threshold, which is less than the eighth preset temperature threshold.

[0113] For the specific implementation process of the two judgments provided above regarding whether the preset exit conditions are met, please refer to... Figure 4 The details of S340 in the illustrated embodiment will not be repeated here.

[0114] S550 controls the power converter to operate according to the initial operating parameters.

[0115] In an optional implementation, the specific execution process of S550 can be referred to Figure 2 The details of S140 in the illustrated embodiment will not be repeated here. It should be noted that the anti-condensation control method provided in this embodiment, which reduces the temperature difference between the device and the internal environment, mainly relies on the control of the operation of the heat dissipation equipment. Therefore, controlling the power converter to run according to the initial operating parameters mainly refers to restoring the operating parameters of the heat dissipation equipment before the execution of S530.

[0116] In summary, the anti-condensation control method provided in this embodiment determines the condensation point temperature of the internal space of the power converter by collecting the current internal ambient humidity through a humidity sensor. It increases the device temperature of the target power device by reducing its heat dissipation efficiency, and further reduces the internal ambient temperature by increasing the heat dissipation efficiency of the internal space of the power converter. This effectively reduces the temperature difference between the device temperature and the internal ambient temperature. By monitoring the temperature difference between the device temperature and the condensation point temperature, it ensures that the device temperature remains above the condensation point temperature, preventing condensation at the target power device and ensuring its insulation performance, thereby improving the safety of the power converter.

[0117] Furthermore, a heater is provided in the power converter. This heater can regulate the internal ambient temperature of the power converter and the temperature of the corresponding power devices, improving the power converter's adaptability to different ambient temperatures. In practical applications, the heater can be composed of an auxiliary power supply and heating resistors, etc. Of course, other types of heaters can also be used. This application does not limit the specific selection of the heater. Based on the premise that the heater can heat the power devices and thus change their temperature, this application provides another anti-condensation control method, see [link to relevant documentation]. Figure 7 As shown, the anti-condensation control method provided in this embodiment includes the following steps.

[0118] S600: Obtain the current device temperature of the target power device and the current internal ambient temperature of the power converter.

[0119] In an optional implementation, the specific execution process of S600 can be referred to Figure 1 The details of S100 in the illustrated embodiment will not be repeated here.

[0120] S610. Determine whether the temperature difference between the current internal ambient temperature and the current device temperature is greater than the first preset temperature threshold. If so, execute S620.

[0121] Calculate the temperature difference between the current internal ambient temperature and the current device temperature of the target power device. If the temperature difference between the current internal ambient temperature and the current device temperature of the target power device is greater than the first preset temperature threshold, it can be determined that the target power device meets the preset condensation condition, and then the subsequent S620 is executed. Conversely, if the temperature difference between the current internal ambient temperature and the current device temperature of the target power device is less than or equal to the first preset temperature threshold, it is determined that the target power device does not meet the preset condensation condition, and the current control flow can be exited.

[0122] S620, Start the heater to heat the target power device.

[0123] The arrangement of the heater within the power converter (which can be an inverter or an energy storage converter) can be found in [reference needed]. Figure 8 As shown, the power converter includes an inverter circuit (or rectifier circuit) and three boost circuits, namely boost circuit 1, boost circuit 2, and boost circuit 3. The output terminals of each boost circuit are connected to the DC side of the inverter circuit. Assuming that any boost circuit includes three power devices (shown in dashed boxes in the figure), under the premise of meeting safety requirements, the heater (shown in circles in the figure) should be placed as close as possible to the power devices. When a power device is used independently, a heater can be set for that power device alone. When two power devices are close to each other, such as when they are used in parallel, a heater can be placed in the middle of the two power devices. In addition, a heater can be set for each power device separately, which is also feasible. Of course, heaters can also be set for power devices in other ways, which will not be described in detail here. This application does not make specific limitations on the setting method of the heater.

[0124] In addition, Figure 8 In the scenario shown, the power devices in boost circuit 2 and boost circuit 3, as well as the two power devices in the inverter circuit, have relatively low device temperatures. Figure 8 The circuit marked "cold" indicates that the temperature of the boost circuit 1 and another power device in the inverter circuit is relatively high. Figure 8 The term "heat" is used in the text. Based on the relevant content of the foregoing embodiments, it is clear that... Figure 8 Power devices marked as "cold" are those that require condensation control.

[0125] Based on the above, if the temperature difference between the current internal ambient temperature and the current device temperature is greater than the first preset temperature threshold, it indicates that the target power device meets the preset condensation conditions. In this case, the heater corresponding to the target power device can be activated to heat the target power device and thus increase the device temperature.

[0126] It is understandable that the efficiency of raising the device temperature by a heater is directly related to the heating power of the heater. The general principle for controlling the operation of the heater is: the greater the temperature difference between the current internal ambient temperature and the current device temperature, the more urgent the need to raise the device temperature, and correspondingly, the greater the heating power of the heater should be.

[0127] Based on the above principles, the anti-condensation control method provided in this embodiment takes the current internal ambient temperature as the reference temperature, first calculates the temperature difference between the current device temperature of the target power device and the reference temperature, uses the obtained result as the auxiliary heating temperature difference, and then determines the target heating power based on the auxiliary heating temperature difference.

[0128] Specifically, this embodiment provides a third preset temperature threshold and a fourth preset temperature threshold, wherein the third preset temperature threshold is greater than the fourth preset temperature threshold. If the obtained auxiliary heating temperature difference is greater than or equal to the third preset temperature threshold, it indicates that the device temperature of the target power device needs to be rapidly increased in a short period of time to avoid condensation as much as possible. In this case, the maximum heating power of the heater can be used as the target heating power. If the obtained auxiliary heating temperature difference is less than the third preset temperature threshold but greater than or equal to the fourth preset temperature threshold, the target heating power can be determined based on the preset conversion factor and the obtained auxiliary heating temperature difference. The preset conversion factor is used to characterize the linear relationship between the auxiliary heating temperature difference and the heater heating power. Based on this, after obtaining the auxiliary heating temperature difference, the product of the auxiliary heating temperature difference and the preset conversion factor is calculated, and the result is the target heating power. Furthermore, if the auxiliary heating temperature difference is less than the fourth temperature threshold, it indicates that the temperature difference between the device temperature and the internal ambient temperature is small, and the possibility of condensation in the target power device is low. In this case, the minimum heating power of the heater can be determined as the target heating power.

[0129] Once the target heating power is determined, the heater of the target power device can be controlled to operate according to the target heating power, thereby increasing the device temperature of the target power device.

[0130] As can be seen from the aforementioned control process, the fourth preset temperature threshold and the first preset temperature threshold can be equal or different. Generally, the fourth preset temperature threshold is greater than the first preset temperature threshold. That is to say, when the auxiliary heating temperature difference is greater than the first preset temperature threshold and less than the fourth preset temperature threshold, the heater is controlled to operate according to the minimum heating power of the heater. This setting can effectively avoid the frequent start of the condensation control process.

[0131] S630. Determine whether the preset exit conditions are met. If yes, execute S640. If no, return to execute S620.

[0132] In one optional implementation, if the temperature difference between the target power device and the internal ambient temperature is less than the seventh preset temperature threshold, it is determined that the preset exit condition is met, and S640 is continued. Conversely, if the temperature difference between the device temperature and the internal ambient temperature is greater than or equal to the seventh preset temperature threshold, it is determined that the preset exit condition is not met, and S620 is returned to be executed to continuously reduce the temperature difference between the device temperature and the internal ambient temperature.

[0133] In another optional implementation, the temperature difference between the device temperature and the maximum operating temperature corresponding to the target power device can also be detected. When the temperature difference between the device temperature and the maximum operating temperature is less than a preset device temperature difference threshold, it is determined that the preset exit condition is met, and then subsequent steps are executed.

[0134] It should be noted that the above provides two optional preset exit conditions. In practical applications, the two are related by OR, meaning that as long as either one is met, the preset exit condition is determined to be satisfied. For the specific implementation process of the aforementioned two methods, please refer to... Figure 3 The details of S230 in the illustrated embodiment will not be described in detail here.

[0135] S640: Control the power converter to operate according to the initial operating parameters.

[0136] In an optional implementation, the specific execution process of S640 can be referred to Figure 2 The details of S140 in the illustrated embodiment will not be repeated here.

[0137] In summary, the anti-condensation control method provided in this embodiment utilizes the heater of the target power device to increase the device temperature, thereby reducing the temperature difference between the device temperature and the internal ambient temperature. This ensures that the device temperature is above the condensation point temperature, preventing condensation at the target power device and guaranteeing its insulation performance. Furthermore, different heating powers can be selected based on the relationship between the auxiliary heating temperature difference and the third and fourth preset temperature thresholds to meet the device temperature regulation requirements in different scenarios. In particular, when the auxiliary heating temperature difference is greater than the third preset temperature threshold, controlling the heater to operate at maximum heating power can quickly increase the device temperature and prevent condensation.

[0138] When a humidity sensor is installed in the power converter, the condensation problem on the power devices can also be solved by heating the power devices with a heater. See also Figure 9 As shown, the anti-condensation control method provided in this embodiment includes the following steps.

[0139] S700: Obtain the current device temperature of the target power device, the current internal ambient temperature of the power converter, and the current internal ambient humidity.

[0140] In an optional implementation, the specific execution process of S700 can be referred to Figure 4 The details of S300 in the illustrated embodiment will not be repeated here.

[0141] S710. Determine the condensation point temperature based on the current internal ambient temperature and humidity.

[0142] In one alternative implementation, the dew point temperature can be calculated with reference to the aforementioned formula (1), which will not be repeated here.

[0143] S720. Determine whether the temperature difference between the current device temperature and the dew point temperature is less than or equal to the second preset temperature threshold. If so, execute S730.

[0144] Calculate the temperature difference between the current device temperature and the dew point temperature of the target power device. If the temperature difference is less than or equal to the second preset temperature threshold, it can be determined that the target power device meets the preset condensation condition, and further execute S730. Conversely, if the temperature difference between the current device temperature and the dew point temperature is greater than the second preset temperature threshold, it indicates that the target power device does not currently meet the preset condensation condition, and the current control flow can be exited without executing subsequent steps.

[0145] S730, start the heater to heat the target power device.

[0146] If the temperature difference between the current device temperature and the dew point temperature is less than or equal to the second preset temperature threshold, it indicates that the target power device meets the preset dew conditions. In this case, the heater corresponding to the target power device can be activated to heat the target power device and thus increase the device temperature.

[0147] Based on the foregoing, the dew point temperature calculated in S710 is used as the reference temperature. First, the temperature difference between the current device temperature and the reference temperature is calculated, and the result is used as the auxiliary heating temperature difference. Then, the target heating power is determined based on the auxiliary heating temperature difference.

[0148] Specifically, this embodiment provides a fifth preset temperature threshold and a sixth preset temperature threshold, wherein the fifth preset temperature threshold is greater than the sixth preset temperature threshold. If the obtained auxiliary heating temperature difference is less than the sixth preset temperature threshold, it indicates that the device temperature of the target power device needs to be rapidly increased in a short period of time to avoid condensation as much as possible. In this case, the maximum heating power of the heater can be used as the target heating power. If the obtained auxiliary heating temperature difference is greater than or equal to the sixth preset temperature threshold and less than the fifth preset temperature threshold, the target heating power can be determined based on the preset conversion factor and the obtained auxiliary heating temperature difference. The preset conversion factor is used to characterize the linear relationship between the auxiliary heating temperature difference and the heater heating power. Based on this, after obtaining the auxiliary heating temperature difference, the product of the auxiliary heating temperature difference and the preset conversion factor is calculated, and the result is the target heating power. Furthermore, if the auxiliary heating temperature difference is greater than or equal to the fifth preset temperature threshold, it indicates that the temperature difference between the device temperature and the condensation point temperature is large, and the possibility of condensation in the target power device is low. In this case, the minimum heating power of the heater can be determined as the target heating power.

[0149] Once the target heating power is determined, the heater of the target power device can be controlled to operate according to the target heating power, thereby increasing the device temperature of the target power device.

[0150] Based on the aforementioned control process, it can be seen that the fifth preset temperature threshold is less than the second preset temperature threshold. In other words, when the auxiliary heating temperature difference is greater than or equal to the fifth preset temperature threshold and less than the second preset temperature threshold, the heater is controlled to operate according to the heater's minimum heating power.

[0151] S740. Determine whether the preset exit conditions are met. If yes, execute S750. If no, return to execute S730.

[0152] It is understood that heating the power device with a heater can increase its temperature. Therefore, in one optional implementation, if the device temperature of the target power device is higher than the dew point temperature obtained in the aforementioned steps, and the temperature difference between the device temperature and the dew point temperature is greater than an eighth preset temperature threshold, then the preset exit condition can be determined to be met. In another optional implementation, when the device temperature of the target power device meets the target condition, the preset exit condition can also be determined to be met. The target condition includes: the temperature difference between the device temperature of the target power device and the maximum operating temperature is less than a preset device temperature difference threshold; and the temperature difference between the device temperature of the target power device and the dew point temperature is greater than a ninth preset temperature threshold, which is less than the eighth preset temperature threshold.

[0153] For the specific implementation process of the two judgments provided above regarding whether the preset exit conditions are met, please refer to... Figure 4The details of S340 in the illustrated embodiment will not be repeated here.

[0154] S750 controls the power converter to operate according to the initial operating parameters.

[0155] In an optional implementation, the specific execution process of S750 can be referred to Figure 2 The details of S140 in the illustrated embodiment will not be repeated here. It should be noted that the anti-condensation control method provided in this embodiment, which reduces the temperature difference between the device and the internal ambient temperature, mainly relies on the control of the heater operation process. Therefore, controlling the power converter to run according to the initial operating parameters mainly refers to restoring the heater's operating parameters before executing S730.

[0156] In summary, the anti-condensation control method provided in this embodiment utilizes the heater of the target power device to increase the device temperature, thereby increasing the temperature difference between the device temperature and the condensation point temperature. This ensures that the device temperature remains above the condensation point temperature, preventing condensation at the target power device and guaranteeing its insulation performance. Furthermore, different heating powers can be selected based on the relationship between the auxiliary heating temperature difference and the fifth and sixth preset temperature thresholds to meet the device temperature regulation requirements in different scenarios. In particular, when the auxiliary heating temperature difference is less than the sixth preset temperature threshold, controlling the heater to operate at maximum heating power can quickly raise the device temperature and prevent condensation.

[0157] The inventors further discovered that during the operation of the power converter, its internal ambient temperature is directly related to the overall power of the power converter and the rate of change of the overall power. Specifically, the higher the overall power, the higher the internal ambient temperature; the higher the rate of increase of the overall power, the higher the internal ambient temperature. By adjusting the overall power of the power converter and the rate of increase of the overall power, the internal ambient temperature can be regulated. Based on this, this application provides another anti-condensation control method, see [link to relevant documentation]. Figure 10 As shown, the anti-condensation control method provided in this embodiment includes the following steps.

[0158] S800: Obtain the current device temperature of the target power device and the current internal ambient temperature of the power converter.

[0159] In an optional implementation, the specific execution process of S800 can be referred to Figure 1 The details of S100 in the illustrated embodiment will not be repeated here.

[0160] S810. Determine whether the temperature difference between the current internal ambient temperature and the current device temperature is greater than the first preset temperature threshold. If so, execute S820.

[0161] As mentioned earlier, the excessive temperature difference between the power device temperature and the internal ambient temperature of the power converter is a key cause of condensation on the power device. Based on this, the temperature difference between the current internal ambient temperature and the current device temperature of the target power device is calculated. If the obtained temperature difference is greater than the first preset temperature threshold, it can be determined that the target power device meets the preset condensation condition, and then the subsequent S820 is executed. Conversely, if the obtained temperature difference is less than or equal to the first preset temperature threshold, it is determined that the target power device does not meet the preset condensation condition, and the current control flow can be exited.

[0162] S820, reduce the overall power of the power converter or reduce the rate of rise of the overall power.

[0163] As mentioned earlier, the higher the overall power, the higher the internal ambient temperature. The higher the rate of increase of the overall power, the higher the internal ambient temperature. Based on this, if the temperature difference between the current internal ambient temperature and the current device temperature is greater than the first preset temperature threshold, it indicates that the target power device meets the preset condensation condition. By reducing the overall power of the power converter or reducing the rate of increase of the overall power, the internal ambient temperature can be reduced, thereby reducing the temperature difference between the device temperature and the internal ambient temperature.

[0164] Understandably, if the power converter is in a stable operating state with a constant overall power, the overall power of the power converter can be reduced. If the overall power of the power converter is increasing, the rate of increase can be reduced to slow down the change in internal ambient temperature, ultimately reducing the temperature difference between the ambient temperature and the device temperature. In practical applications, the specific adjustment method can be selected based on the current state of the power converter. The specific control process for reducing the overall power and the rate of increase of the overall power can be found in relevant technical documents on power converter control processes, and will not be detailed here.

[0165] S830: Determine whether the temperature difference between the device temperature and the internal ambient temperature is less than the seventh preset temperature threshold. If yes, execute S840; otherwise, return to execute S820.

[0166] As mentioned above, if the temperature difference between the device temperature and the internal ambient temperature is small enough, the possibility of condensation on the power device is extremely low. Based on this, as an optional preset exit condition, if the temperature difference between the device temperature and the internal ambient temperature is less than the seventh preset temperature threshold, it is determined that the preset exit condition is met and S840 is executed. Conversely, if the temperature difference between the device temperature and the internal ambient temperature is greater than or equal to the seventh preset temperature threshold, it is determined that the preset exit condition is not met and S820 is executed again to continuously reduce the temperature difference between the device temperature and the internal ambient temperature.

[0167] It should be noted that the aforementioned first preset temperature threshold is used to determine whether to reduce the internal ambient temperature. The seventh preset temperature threshold mentioned in this embodiment is used to determine whether the preset exit condition is met and the normal operation of the power converter is restored. It can be seen that the first preset temperature threshold and the seventh preset temperature threshold can be equal or unequal. Considering that if the first preset temperature threshold and the seventh preset temperature threshold are equal, it is easy to cause frequent switching between the condensation control process and the control process during normal operation of the power converter. Generally, the first preset temperature threshold is made to be greater than the seventh preset temperature threshold, and both the first preset temperature threshold and the seventh preset temperature threshold are greater than zero.

[0168] S840 controls the power converter to operate according to the initial operating parameters.

[0169] In an optional implementation, the specific execution process of S840 can be referred to Figure 2 The details of S140 in the illustrated embodiment will not be repeated here.

[0170] In summary, the anti-condensation control method provided in this embodiment reduces the internal ambient temperature by reducing the overall power or the rate of increase of the overall power, thereby reducing the condensation point temperature, increasing the temperature difference between the device temperature and the condensation point temperature, and thus reducing the temperature difference between the device temperature and the internal ambient temperature. This prevents condensation from occurring at the target power device, ensures the insulation performance of the target power device, and improves the safety of the power converter.

[0171] When a humidity sensor is installed in the power converter, the condensation problem on the target power device can also be solved by adjusting the overall power and the rate of increase of the overall power. See also Figure 11 As shown, the anti-condensation control method provided in this embodiment includes the following steps.

[0172] S900: Obtain the current device temperature of the target power device, the current internal ambient temperature of the power converter, and the current internal ambient humidity.

[0173] In an optional implementation, the specific execution process of S900 can be referred to Figure 4 The details of S300 in the illustrated embodiment will not be repeated here.

[0174] S910. Determine the condensation point temperature based on the current internal ambient temperature and humidity.

[0175] In one alternative implementation, the dew point temperature can be calculated with reference to the aforementioned formula (1), which will not be repeated here.

[0176] S920. Determine whether the temperature difference between the current device temperature and the dew point temperature is less than or equal to the second preset temperature threshold. If so, execute S930.

[0177] Calculate the temperature difference between the current device temperature and the dew point temperature of the target power device. If the temperature difference is less than or equal to the second preset temperature threshold, it can be determined that the target power device meets the preset condensation condition, and further execute S930. Conversely, if the temperature difference between the current device temperature and the dew point temperature of the target power device is greater than the second preset temperature threshold, it indicates that the target power device does not currently meet the preset condensation condition, and the current control flow can be exited without executing subsequent steps.

[0178] S930, reduce the overall power of the power converter or reduce the rate of rise of the overall power.

[0179] In an optional implementation, the specific execution process of S930 can be referred to Figure 10 The details of S820 in the illustrated embodiment will not be repeated here.

[0180] S940. Determine whether the preset exit conditions are met. If yes, execute S950. If no, return to execute S930.

[0181] Based on the foregoing, the greater the temperature difference between the device temperature and the dew point temperature, the lower the probability of condensation occurring on the power device. Therefore, in an optional implementation, if the device temperature of the target power device is higher than the dew point temperature obtained in the aforementioned steps, and the temperature difference between the device temperature and the dew point temperature is greater than the eighth preset temperature threshold, then the preset exit condition can be determined to be met.

[0182] It is understandable that by reducing the overall power of the power converter or reducing the rate of increase of the overall power, the internal ambient temperature of the internal space of the power converter can be reduced. As the internal ambient temperature decreases, the corresponding dew point temperature of the internal space will also decrease. Based on this, in another optional implementation, the dew point temperature can be calculated again in this step using the aforementioned formula (1). If the device temperature of the target power device is higher than the dew point temperature calculated at this time, and the temperature difference between the device temperature and the dew point temperature is greater than the tenth preset temperature threshold, then the preset exit condition can be determined to be met. Since the dew point temperature decreases, the tenth preset temperature threshold is greater than the aforementioned eighth preset temperature threshold.

[0183] S950 controls the power converter to operate according to the initial operating parameters.

[0184] In an optional implementation, the specific execution process of S950 can be referred to Figure 2 The details of S140 in the illustrated embodiment will not be repeated here.

[0185] In summary, the anti-condensation control method provided in this embodiment reduces the internal ambient temperature by reducing the overall power or the rate of increase of the overall power, thereby lowering the condensation point temperature, increasing the temperature difference between the device temperature and the condensation point temperature, preventing condensation from occurring at the target power device, ensuring the insulation performance of the target power device, and improving the safety of the power converter.

[0186] As mentioned earlier, condensation can be controlled by increasing the device temperature and / or decreasing the internal ambient temperature. Specifically, the device temperature can be increased by at least one of the following methods: increasing the loss of the target power device, reducing the heat dissipation efficiency of the target power device, and activating the heater to heat the target power device. Conversely, the internal ambient temperature can be decreased by at least one of the following methods: improving the heat dissipation efficiency of the internal space of the power converter, reducing the overall power of the power converter, and reducing the rate of increase of the overall power. Therefore, in practical applications, different control methods can be combined to obtain different anti-condensation control methods. The following describes the condensation control process using the example of increasing the loss of the target power device and activating the heater corresponding to the target power device simultaneously, without installing a humidity sensor in the power converter. Other possible combinations can be implemented with reference to the relevant content of this embodiment and the foregoing embodiments, and will not be listed here. Other anti-condensation control methods obtained by combining these methods without exceeding the core concept of this application also fall within the scope of protection of this application.

[0187] See Figure 12 As shown, the anti-condensation control method provided in this embodiment includes the following steps.

[0188] S1000: Obtain the current device temperature of the target power device and the current internal ambient temperature of the power converter.

[0189] In one optional implementation, the specific execution process of S1000 can be referred to Figure 1 The details of S100 in the illustrated embodiment will not be repeated here.

[0190] S1010: Determine whether the temperature difference between the current internal ambient temperature and the current device temperature is greater than the first preset temperature threshold. If so, execute S1020.

[0191] Calculate the temperature difference between the current internal ambient temperature and the current device temperature of the target power device. If the temperature difference between the current internal ambient temperature and the current device temperature is greater than the first preset temperature threshold, it can be determined that the target power device meets the preset condensation condition, and then the subsequent S1020 is executed. Conversely, if the temperature difference between the current internal ambient temperature and the current device temperature of the target power device is less than or equal to the first preset temperature threshold, it is determined that the target power device does not meet the preset condensation condition, and the current control flow can be exited.

[0192] S1020, Increase the loss of the target power device and start the heater to heat the target power device.

[0193] The specific implementation process for increasing the loss of the target power device, in conjunction with the foregoing embodiments, can be referred to... Figure 3 The implementation details of S220 in the illustrated embodiment will not be repeated here. For the specific implementation process of activating the heater corresponding to the target power device, please refer to [link / reference needed]. Figure 7 The implementation details of S620 in the illustrated embodiment will not be repeated here.

[0194] S1030. Determine whether the preset exit conditions are met. If yes, execute S1040. If no, return to execute S1020.

[0195] Increasing the losses of the target power device and activating the heater of the target power device can both raise the device temperature. If the temperature difference between the device temperature and the internal ambient temperature is small enough, the possibility of condensation on the target power device is extremely low. Based on this, as an optional preset exit condition, if the temperature difference between the device temperature and the internal ambient temperature is less than the seventh preset temperature threshold, it is determined that the preset exit condition is met and S1040 is continued. Conversely, if the temperature difference between the device temperature and the internal ambient temperature is greater than or equal to the seventh preset temperature threshold, it is determined that the preset exit condition is not met and S1020 is returned to be executed to continuously reduce the temperature difference between the device temperature and the internal ambient temperature.

[0196] In another optional implementation, the temperature difference between the device temperature and the maximum operating temperature of the target power device can also be detected. When the temperature difference between the device temperature and the maximum operating temperature is less than a preset device temperature difference threshold, it is determined that the preset exit condition is met, and then subsequent steps are executed.

[0197] The specific implementation of the above judgment process can be referred to the foregoing. Figure 3 The details of S230 in the illustrated embodiment will not be repeated here.

[0198] S1040: Control the power converter to operate according to the initial operating parameters.

[0199] In an optional implementation, the specific execution process of S1040 can be referred to Figure 2 The details of S140 in the illustrated embodiment will not be repeated here.

[0200] In summary, the anti-condensation control method provided in this embodiment increases the loss of the target power device while simultaneously activating the heater to heat the target power device. This two-pronged approach significantly increases the rate of temperature rise, reduces the temperature difference between the device and the internal environment in a short time, effectively prevents condensation on the target power device, and improves the safety of the power converter.

[0201] As can be seen from the execution process of the anti-condensation control methods provided in the above embodiments, the anti-condensation control methods provided in the embodiments of this application only require adjustments to the device temperature and the internal ambient temperature to prevent condensation on power devices. This approach is low-cost, with simple control logic that is easy to implement. By preventing condensation on power devices, critical components in the power converter can be protected, thereby extending the lifespan of the power converter. Especially in photovoltaic systems, energy storage systems, or industrial power systems, the inverter is one of the core devices. The anti-condensation control methods provided in the embodiments of this application prevent condensation from damaging the insulation of power devices and causing inverter failure, thus ensuring the stable operation of the entire system. Simultaneously, it also improves the safety of the power converter and the system to which it belongs.

[0202] Below, for reference Figure 13 The controller provided in this embodiment of the invention may include at least one processor 100, at least one communication interface 200, at least one memory 300, and at least one communication bus 400. In this embodiment of the invention, the number of processor 100, communication interface 200, memory 300, and communication bus 400 is at least one, and the processor 100, communication interface 200, and memory 300 communicate with each other through communication bus 400; obviously, Figure 13 The communication connections shown for the processor 100, communication interface 200, memory 300, and communication bus 400 are optional. Optionally, the communication interface 200 can be an interface of a communication module, such as the interface of a GSM module; the processor 100 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention.

[0203] The memory 300 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0204] Specifically, the processor 100 is used to execute the application program in the memory to implement the steps of the anti-condensation control method described above.

[0205] This application embodiment also provides a power converter, including: multiple power devices, a first temperature detector, a second temperature detector, and a controller, wherein, The first temperature detector is configured to detect the device temperature of the power device; The second temperature detector is configured to detect the internal ambient temperature of the power converter; The controller is connected to the first temperature detector and the second temperature detector respectively, and the controller is configured to perform the steps of the anti-condensation control method provided in any of the foregoing embodiments to perform anti-condensation control on the power devices.

[0206] In some embodiments, this embodiment also provides a computer-readable storage medium, such as a floppy disk, optical disk, hard disk, flash memory, USB flash drive, SD (Secure Digital Memory Card), MMC (Multimedia Card), etc., in which one or more instructions for implementing the above steps are stored. When these one or more instructions are executed by one or more processors, the processors perform the anti-condensation control method described above. For specific implementation details, please refer to the foregoing description; further elaboration is not provided here.

[0207] In addition to the methods and devices described above, embodiments of this application may also be computer program products, which include computer program instructions that, when executed by a processor, cause the processor to perform the steps in the anti-condensation control methods according to various embodiments of this application as described above.

[0208] Computer program products can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments of this application. The programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or controller.

[0209] Those skilled in the art will understand that the contents disclosed herein can be varied and modified in many ways. For example, the various devices or components described above can be implemented in hardware, or in software, firmware, or a combination of some or all of the three.

[0210] Furthermore, while this disclosure makes various references to certain units in systems according to embodiments of this disclosure, any number of different units may be used and operated on clients and / or controllers. The units are merely illustrative, and different aspects of the system and method may use different units.

[0211] This disclosure uses flowcharts to illustrate the steps of a method according to embodiments of this disclosure. It should be understood that the preceding or following steps are not necessarily performed in exact order. Instead, the steps can be processed in reverse order or simultaneously. Furthermore, other operations can be added to these processes.

[0212] Those skilled in the art will understand that all or part of the steps in the above methods can be implemented by a computer program instructing related hardware, and the program can be stored in a computer-readable storage medium, such as a read-only memory. Optionally, all or part of the steps in the above embodiments can also be implemented using one or more integrated circuits. Accordingly, each module / unit in the above embodiments can be implemented in hardware or as a software functional module. This disclosure is not limited to any particular combination of hardware and software.

[0213] Unless otherwise defined, all terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It should also be understood that terms such as those defined in a common dictionary should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and not as having an idealized or highly formalized meaning, unless expressly defined herein.

[0214] The foregoing description is intended to illustrate the present disclosure and should not be construed as limiting it. While several exemplary embodiments of the present disclosure have been described, those skilled in the art will readily understand that many modifications may be made to the exemplary embodiments without departing from the novel teachings and advantages of the present disclosure. Therefore, all such modifications are intended to be included within the scope of the present disclosure as defined by the claims. It should be understood that the foregoing description is intended to illustrate the present disclosure and should not be construed as limiting it to the specific embodiments disclosed, and modifications to the disclosed embodiments and other embodiments are intended to be included within the scope of the appended claims. The present disclosure is defined by the claims and their equivalents.

Claims

1. A method for preventing condensation control, characterized in that, The method includes: The current device temperature of the target power device in the power converter and the current internal ambient temperature of the power converter are obtained, wherein the power converter includes multiple power devices, and the target power device is any one of the multiple power devices; If the target power device is determined to meet the preset condensation conditions based on the current device temperature and the current internal ambient temperature, then the temperature difference between the device temperature of the target power device and the internal ambient temperature of the power converter is reduced.

2. The method according to claim 1, characterized in that, The step of determining whether the target power device meets the preset condensation conditions based on the current device temperature and the current internal ambient temperature includes: If the temperature difference between the current internal ambient temperature and the current device temperature is greater than a first preset temperature threshold, it is determined that the target power device meets the preset condensation condition. or, If the temperature difference between the current device temperature and the dew point temperature is less than or equal to the second preset temperature threshold, it is determined that the target power device meets the preset condensation condition. The dew point temperature is determined based on the internal ambient temperature and is the temperature at which condensation occurs on the power device.

3. The method according to claim 2, characterized in that, The process of determining the dew point temperature includes: Obtain the current internal humidity of the power converter; The condensation point temperature is determined based on the current internal humidity and the current internal temperature.

4. The method according to claim 1, characterized in that, The reduction of the temperature difference between the target power device temperature and the internal ambient temperature of the power converter includes: Increase the device temperature of the target power device; And / or, Reduce the internal ambient temperature of the power converter.

5. The method according to claim 4, characterized in that, The process of raising the device temperature of the target power device includes: The device temperature of the target power device is increased by at least one of the following heating methods: Increase the loss of the target power device, reduce the heat dissipation efficiency of the target power device, and start the heater to heat the target power device.

6. The method according to claim 5, characterized in that, The increase in the loss of the target power device includes: Increase the duty cycle of the control signal of the target power device, and / or increase the signal frequency of the control signal of the target power device.

7. The method according to claim 5, characterized in that, The power converter is equipped with a wind-cooled heat dissipation device corresponding to the target power device. The reduction of the heat dissipation efficiency of the target power device includes: Reduce the airflow speed of the air-cooled heat dissipation device corresponding to the target power device, or adjust the airflow direction of the air-cooled heat dissipation device corresponding to the target power device to a direction away from the target power device.

8. The method according to claim 5, characterized in that, The power converter is equipped with a liquid cooling heat dissipation device corresponding to the target power device. The reduction of the heat dissipation efficiency of the target power device includes: Reduce the flow rate of the coolant in the liquid cooling device corresponding to the target power device.

9. The method according to claim 5, characterized in that, The power converter is equipped with a heater corresponding to the target power device; Starting the heater to heat the target power device includes: The temperature difference between the current device temperature and the reference temperature is defined as the auxiliary heating temperature difference. The reference temperature includes the current internal ambient temperature or the dew point temperature. The dew point temperature is determined based on the internal ambient temperature and is the temperature at which condensation occurs on the power device. The target heating power is determined based on the auxiliary heating temperature difference, and the heater corresponding to the target power device is controlled to operate according to the target heating power.

10. The method according to claim 9, characterized in that, The reference temperature is the current internal ambient temperature, and the step of determining the target heating power based on the auxiliary heating temperature difference includes: If the auxiliary heating temperature difference is greater than or equal to the third preset temperature threshold, the maximum heating power of the heater is determined to be the target heating power; If the auxiliary heating temperature difference is less than the third preset temperature threshold and the auxiliary heating temperature difference is greater than or equal to the fourth preset temperature threshold, the target heating power is determined based on the preset conversion factor and the auxiliary heating temperature difference. The preset conversion factor is used to characterize the linear relationship between the auxiliary heating temperature difference and the heater heating power. If the auxiliary heating temperature difference is less than the fourth preset temperature threshold, the minimum heating power of the heater is determined to be the target heating power, and the third preset temperature threshold is greater than the fourth preset temperature threshold.

11. The method according to claim 9, characterized in that, The reference temperature is the dew point temperature, and the step of determining the target heating power based on the auxiliary heating temperature difference includes: If the auxiliary heating temperature difference is greater than or equal to the fifth preset temperature threshold, the minimum heating power of the heater is determined to be the target heating power; If the auxiliary heating temperature difference is less than the fifth preset temperature threshold and the auxiliary heating temperature difference is greater than or equal to the sixth preset temperature threshold, the target heating power is determined based on the preset conversion factor and the auxiliary heating temperature difference. The preset conversion factor is used to characterize the linear relationship between the auxiliary heating temperature difference and the heater heating power. If the auxiliary heating temperature difference is less than the sixth preset temperature threshold, the maximum heating power of the heater is determined to be the target heating power, and the fifth preset temperature threshold is greater than the sixth preset temperature threshold.

12. The method according to claim 4, characterized in that, The reduction of the internal ambient temperature of the power converter includes: The internal ambient temperature of the power converter shall be reduced by at least one of the following cooling measures: Improve the heat dissipation efficiency of the internal environment of the power converter, reduce the overall power of the power converter, and reduce the rate of increase of the overall power.

13. The method according to claim 12, characterized in that, The power converter is equipped with heat dissipation devices corresponding to each of the power devices. Improving the heat dissipation efficiency of the internal environment of the power converter includes: Improve the heat dissipation efficiency of heat dissipation devices other than the heat dissipation device corresponding to the target power device.

14. The method according to any one of claims 1 to 13, characterized in that, Also includes: If the preset exit conditions are met, the power converter is controlled to operate according to the initial operating parameters, which include the operating parameters of the power converter before reducing the temperature difference between the target power device temperature and the internal ambient temperature of the power converter.

15. The method according to claim 14, characterized in that, The preset exit conditions include: The temperature difference between the target power device temperature and the internal ambient temperature of the power converter is less than a seventh preset temperature threshold, or the temperature difference between the target power device temperature and the maximum operating temperature corresponding to the target power device is less than a preset device temperature difference threshold.

16. The method according to claim 14, characterized in that, The preset exit conditions include: The temperature difference between the device temperature and the dew point temperature of the target power device is greater than the eighth preset temperature threshold, or the device temperature of the target power device meets the target condition. The target conditions include: the temperature difference between the device temperature of the target power device and the maximum operating temperature of the target power device is less than a preset device temperature difference threshold, and the temperature difference between the device temperature of the target power device and the dew point temperature is greater than a ninth preset temperature threshold. The dew point temperature is determined based on the internal ambient temperature and is the temperature at which condensation occurs on the power device. The ninth preset temperature threshold is less than the eighth preset temperature threshold.

17. A controller, characterized in that, The method includes a memory, a processor, and a computer program stored in the memory and executed by the processor, characterized in that the processor executes the computer program to implement the steps of the anti-condensation control method as described in any one of claims 1 to 16.

18. A power converter, characterized in that, include: Multiple power devices, a first temperature detector, a second temperature detector, and a controller, wherein, The first temperature detector is configured to detect the device temperature of the power device; The second temperature detector is configured to detect the internal ambient temperature of the power converter; The controller is connected to the first temperature detector and the second temperature detector respectively, and the controller is configured to perform the steps of the anti-condensation control method as described in any one of claims 1 to 16 to perform anti-condensation control on the power device.

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