Overcurrent detection circuit and laundry treating apparatus

Abstract

The application provides an overcurrent detection circuit and a clothes processing device, and belongs to the field of home appliance control. A sampling module is connected with an intelligent power module, collects three-phase current signals, and obtains bus detection signals. A signal processing module is connected with the sampling module, compares the bus detection signals with reference voltage signals, obtains a comparison result signal, converts the comparison result signal, and obtains an overcurrent detection signal. The signal processing module is connected with the intelligent power module, and sends the overcurrent detection signal to the intelligent power module. The overcurrent detection is indirectly realized through the circuit, the collected three-phase current signals and the overcurrent detection signal are fully signal-isolated, the isolation between different signal ports of the intelligent power module is realized, and the problem of low overcurrent detection accuracy of the traditional circuit is solved.

Description

Technical Field

[0001] This application belongs to the field of home appliance control technology, and in particular relates to an overcurrent detection circuit and a clothing processing device. Background Technology

[0002] Electronic commutation technology for direct-drive motors and brushless DC motors effectively solves the problems of short lifespan, high noise, and electromagnetic interference caused by carbon brush commutation in brushed motors, and is increasingly being used in clothing handling equipment (such as washing machines or dryers). Electronic commutation technology is implemented through Intelligent Power Modules (IPMs).

[0003] In traditional circuits, the three-phase current is directly sampled through resistors and then sent to the intelligent power module (IPM) for overcurrent detection. However, since the motor is an inductive load, directly sampling the current through resistors is prone to generating interference signals, resulting in low accuracy of overcurrent detection. This can cause the IPM to malfunction, affecting the normal operation of the motor. Utility Model Content

[0004] The purpose of this application is to provide an overcurrent detection circuit and a garment processing device, which aims to solve the problem of low accuracy of overcurrent detection in traditional circuits.

[0005] This application provides an overcurrent detection circuit, including:

[0006] The sampling module, connected to the intelligent power module, is used to collect the three-phase current signal provided by the intelligent power module and obtain the bus detection signal;

[0007] A signal processing module, connected to the sampling module, is used to compare the bus detection signal with the reference voltage signal to obtain a comparison result signal, and to convert the comparison result signal to obtain an overcurrent detection signal;

[0008] The signal processing module is also connected to the intelligent power module and is used to send the overcurrent detection signal to the intelligent power module.

[0009] In some embodiments of this application, the signal processing module includes:

[0010] The comparison module, connected to the sampling module, is used to output a first comparison result signal when the bus detection signal is less than the reference voltage signal;

[0011] Alternatively, the comparison module is further configured to output a second comparison result signal when the bus detection signal is greater than the reference voltage signal.

[0012] In some embodiments of this application, the signal processing module further includes:

[0013] A switching module, connected to the comparison module, is used to cut off the current detection signal based on the first comparison result signal or to turn on the current detection signal based on the second comparison result signal.

[0014] In some embodiments of this application, the overcurrent detection circuit further includes:

[0015] A filtering module, connected to the signal processing module, is used to filter the overcurrent detection signal to obtain a filtered overcurrent detection signal.

[0016] The filtering module is also connected to the intelligent power module, and sends the filtered overcurrent detection signal to the intelligent power module.

[0017] In some embodiments of this application, the comparison module includes:

[0018] The comparator has its inverting input connected to the sampling module to acquire the bus detection signal, and its non-inverting input to acquire the reference voltage signal.

[0019] The comparator is used to output the first comparison result signal when the bus detection signal is less than the reference voltage signal;

[0020] Alternatively, the comparator is further configured to output the second comparison result signal when the bus detection signal is greater than the reference voltage signal.

[0021] In some embodiments of this application, the comparison module further includes:

[0022] A reference conversion module, wherein the first terminal of the reference conversion module is used to acquire the control side voltage signal, the second terminal of the reference conversion module is used to acquire the first voltage signal, and the third terminal of the reference conversion module outputs the reference voltage signal to the non-inverting input terminal of the comparator;

[0023] The reference conversion module is used to perform voltage conversion on the control-side voltage signal to obtain the reference voltage signal.

[0024] In some embodiments of this application, the reference conversion module includes:

[0025] A first resistor, one end of which is used to acquire the control-side voltage signal, and the other end of which is connected to the non-inverting input of the comparator;

[0026] The second resistor has one end connected to the non-inverting input of the comparator and the other end grounded.

[0027] A third resistor, one end of which is used to acquire the first voltage signal, and the other end of which is connected to the non-inverting input of the comparator;

[0028] A first capacitor, one end of which is connected to the non-inverting input of the comparator, and the other end of which is grounded.

[0029] In some embodiments of this application, the switching module includes:

[0030] A P-type transistor, wherein the first terminal of the P-type transistor is connected to the output terminal of the comparison module for acquiring the first comparison result signal or the second comparison result signal, the second terminal of the P-type transistor is used to acquire the first voltage signal, and the third terminal of the P-type transistor is used to output the overcurrent detection signal;

[0031] The P-type transistor is either a P-type bipolar transistor or a P-type field-effect transistor.

[0032] In some embodiments of this application, the switch module further includes:

[0033] A fourth resistor, one end of which is connected to the third terminal of the P-type transistor, and the other end of which outputs the overcurrent detection signal;

[0034] The fifth resistor has one end connected to the other end of the fourth resistor, and the other end of the fifth resistor is grounded.

[0035] In some embodiments of this application, the filtering module includes:

[0036] A sixth resistor, one end of which is connected to the signal processing module to acquire the overcurrent detection signal, and the other end of which is connected to the detection pin of the intelligent power module;

[0037] The second capacitor has one end connected to the other end of the sixth resistor and the detection pin of the intelligent power module, and the other end of the second capacitor is grounded.

[0038] In some embodiments of this application, the sampling module includes:

[0039] The seventh resistor has one end connected to the negative terminal pin of the first phase current of the intelligent power module, and the other end grounded.

[0040] An eighth resistor, one end of which is connected to one end of the seventh resistor, and the other end of which is connected to the signal processing module;

[0041] The ninth resistor has one end connected to the negative terminal pin of the second phase current of the intelligent power module, and the other end grounded.

[0042] The tenth resistor has one end connected to one end of the ninth resistor and the other end connected to the other end of the eighth resistor.

[0043] The eleventh resistor has one end connected to the negative terminal pin of the third phase current of the intelligent power module, and the other end grounded.

[0044] The twelfth resistor has one end connected to one end of the eleventh resistor and the other end connected to the other end of the eighth resistor.

[0045] The third capacitor has one end connected to the other end of the eighth resistor, and the other end of the third capacitor is grounded.

[0046] In some embodiments of this application, the intelligent power module is connected to the load and is used to control the operating state of the load according to the overcurrent detection signal.

[0047] This application provides a garment processing device, including any of the overcurrent detection circuits described in the above embodiments.

[0048] The beneficial effects of this utility model embodiment compared with the prior art are:

[0049] The overcurrent detection circuit provided in this application includes a sampling module and a signal processing module. These modules can acquire three-phase current signals, obtain a bus detection signal, compare the bus detection signal with a reference voltage signal to obtain a comparison result signal, and convert the comparison result signal to obtain an overcurrent detection signal. This allows the intelligent power module to more accurately adjust its operating state based on the overcurrent detection signal. Furthermore, the overcurrent detection circuit provided in this application effectively isolates the acquired three-phase current signal from the overcurrent detection signal, achieving isolation between different signal ports of the intelligent power module. This avoids interference signals generated by direct sampling of three-phase current by resistors in traditional circuits, filters out noise interference, and improves the accuracy of overcurrent detection. Therefore, the overcurrent detection circuit provided in this application solves the problem of low overcurrent detection accuracy in traditional circuits. Attached Figure Description

[0050] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or exemplary technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0051] Figure 1 The structural block diagrams of the overcurrent detection circuits provided in some embodiments of this application are shown.

[0052] Figure 2 The connection structure block diagrams of the comparison module, the switching module, and the filtering module in some embodiments provided in this application are shown.

[0053] Figure 3 The diagram shows the specific circuit connection structure of the overcurrent detection circuit in some embodiments provided in this application.

[0054] Figure 4 The following is a schematic diagram of the specific circuit connection structure of the comparison module in some embodiments provided in this application.

[0055] Figure 5 The circuit connection structure diagram of the P-type bipolar transistor in some embodiments provided in this application is shown.

[0056] Figure 6 The circuit connection structure diagram of the P-type field-effect transistor in some embodiments provided in this application is shown.

[0057] Figure 7 The following are schematic diagrams illustrating the specific circuit connection structure of the filtering module in some embodiments provided in this application.

[0058] Figure 8 The following are schematic diagrams illustrating the specific circuit connection structure of the sampling module in some embodiments provided in this application.

[0059] Figure 9 A schematic diagram of the circuit structure of the fault signal output pin of the intelligent power module in some embodiments provided in this application. Detailed Implementation

[0060] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0061] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0062] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0063] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature. Additionally, in the embodiments of this application, the terms "first" and "second" are used to distinguish identical or similar items that have substantially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or order of execution, and that "first" and "second" do not necessarily imply difference.

[0064] In the description of this application, unless otherwise stated, " / " indicates that the objects before and after it are in an "or" relationship. For example, A / B can mean A or B. "And / or" in this application is merely a description of the relationship between the related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone, where A and B can be singular or plural. Furthermore, in the description of this application, unless otherwise stated, "multiple" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0065] Please see Figure 1 This application provides an overcurrent detection circuit 100. The overcurrent detection circuit 100 includes a sampling module 10 and a signal processing module 20. The sampling module 10 is connected to an intelligent power module 200 and is used to acquire the three-phase current signal provided by the intelligent power module 200 to obtain the bus detection signal.

[0066] The signal processing module 20 is connected to the sampling module 10 and is used to compare the bus detection signal with the reference voltage signal to obtain a comparison result signal. The comparison result signal is then converted to obtain an overcurrent detection signal. The signal processing module 20 is also connected to the intelligent power module 200 and is used to send the overcurrent detection signal to the intelligent power module 200.

[0067] In this embodiment, the intelligent power module 200 is a high-performance modular device integrating power semiconductor devices, drive circuits, protection circuits, and interface circuits, capable of motor drive and power electronic conversion. The sampling module 10 is connected to the intelligent power module 200 and can acquire three-phase current signals, such as U-phase, V-phase, and W-phase current signals. Furthermore, the three-phase current signals provided by the intelligent power module 200 are sampled by the sampling module 10, converged, and expressed as voltage signals to form a bus detection signal. The bus detection signal reflects changes in the bus current. Therefore, after acquiring the bus detection signal through the sampling module 10, it is sent to the signal processing module 20 for comparison with a reference voltage signal.

[0068] The reference voltage signal can be understood as a reference voltage signal for the bus detection signal, or as a threshold voltage for determining whether the bus detection signal is overcurrent. The signal processing module 20 uses the reference voltage signal as a reference point to compare the bus detection signal with the reference voltage signal to distinguish between them and obtain a comparison result signal. The comparison result signal reflects the comparison result between the bus detection signal and the reference voltage signal. Furthermore, the signal processing module 20 converts the comparison result signal, implementing a signal conversion function to adapt the obtained overcurrent detection signal to the driving requirements of the intelligent power module 200, thereby more accurately adjusting the operating state of the intelligent power module 200, such as normal operation or output shutdown, to avoid equipment damage or safety accidents.

[0069] Therefore, through the sampling module 10 and signal processing module 20 in the overcurrent detection circuit 100 provided in this application, the three-phase current signal can be acquired to obtain the bus detection signal. The bus detection signal is then compared with the reference voltage signal to obtain the comparison result signal. This comparison result signal is then converted to obtain the overcurrent detection signal, indirectly achieving overcurrent detection. Furthermore, the overcurrent detection circuit 100 provided in this application effectively isolates the acquired three-phase current signal from the overcurrent detection signal, achieving isolation between different signal ports of the intelligent power module 200. This avoids interference signals generated by the direct sampling of three-phase current by resistors in traditional circuits, filters out noise interference, and improves the accuracy of overcurrent detection. Thus, the overcurrent detection circuit 100 provided in this application solves the problem of low overcurrent detection accuracy in traditional circuits.

[0070] In some embodiments of this application, the sampling module 10 is connected to the negative phase current pins (e.g., NU pin, NV pin, and NW pin) of the intelligent power module 200, and can acquire the U-phase current signal, V-phase current signal, and W-phase current signal. The signal processing module 20 is connected to the detection pins (e.g., CSC pin) of the intelligent power module 200, and can send overcurrent detection signals to the detection pins (e.g., CSC pin) of the intelligent power module 200.

[0071] In some embodiments of this application, when the voltage detected by the detection pin (e.g., CSC pin) of the intelligent power module 200 is greater than a set threshold voltage, the intelligent power module 200 shuts down the three-phase outputs of U-phase, V-phase, and W-phase. This can also be understood as shutting down the outputs of the VSU pin, VSV pin, and VSW pin, preventing the load (e.g., a direct-drive motor, a brushless DC motor, etc.) from operating. Simultaneously, a fault signal is output to the microcontroller unit (MCU) via the fault signal output pin (e.g., FO pin) of the intelligent power module 200, triggering a corresponding alarm mechanism. When the voltage detected by the detection pin (e.g., CSC pin) of the intelligent power module 200 is less than a set threshold voltage, the intelligent power module 200 maintains the normal outputs of U-phase, V-phase, and W-phase, allowing the load (e.g., a direct-drive motor, a brushless DC motor, etc.) to operate normally.

[0072] In some embodiments of this application, the threshold voltage can be set to 0.3V to 0.6V, and the specific threshold voltage can also be adjusted according to the actual application scenario.

[0073] Please see Figure 2 In some embodiments of this application, the signal processing module 20 includes a comparison module 210. The comparison module 210 is connected to the sampling module 10 and is used to output a first comparison result signal when the bus detection signal is less than the reference voltage signal.

[0074] Alternatively, the comparison module 210 is also used to output a second comparison result signal when the bus detection signal is greater than the reference voltage signal.

[0075] In this embodiment, the comparison result signal includes a first comparison result signal and a second comparison result signal, which can reflect the comparison result between the bus detection signal and the reference voltage signal. The comparison module 210 is connected to the sampling module 10 to acquire the bus detection signal. By comparing the bus detection signal and the reference voltage signal through the comparison module 210, high-precision comparison can be achieved, and the output first comparison result signal or second comparison result signal is isolated from the bus detection signal, improving anti-interference capability and avoiding signal interference. Furthermore, the subsequent circuit of the comparison module 210 obtains the overcurrent detection signal based on the first comparison result signal or the second comparison result signal, solving the problem of low overcurrent detection accuracy in traditional circuits.

[0076] Furthermore, by adjusting the reference voltage signal, different reference points can be set to achieve different overcurrent points, thus addressing various application scenarios and enabling the monitoring of bus current overcurrent. This effectively solves the problem of false tripping of the overcurrent protection in the intelligent power module 200. Therefore, by adjusting the reference voltage signal of the signal processing module 20, different overcurrent points can be detected conveniently, safely, and reliably, improving applicability and flexibility. This allows for wider application in different scenarios, ensuring product quality.

[0077] In some embodiments of this application, the signal processing module 20 further includes a switching module 220. The switching module 220 is connected to the comparison module 210 and is used to output an overcurrent detection signal by cutting off the signal based on a first comparison result signal or by turning it on based on a second comparison result signal.

[0078] In this embodiment, when the bus detection signal is less than the reference voltage signal, the comparison module 210 outputs a first comparison result signal to the switch module 220. The switch module 220 is turned off according to the first comparison result signal and does not conduct, and the output overcurrent detection signal has the opposite level to the first comparison result signal.

[0079] When the bus detection signal is greater than the reference voltage signal, the comparison module 210 outputs a second comparison result signal to the switch module 220. The switch module 220 is activated based on the second comparison result signal, and the output overcurrent detection signal has the opposite level to the second comparison result signal. Furthermore, by converting the first or second comparison result signal through the switch module 220, the bus detection signal and the overcurrent detection signal can be further isolated based on the comparison module 210, thereby achieving signal isolation between the acquired three-phase current signal and the overcurrent detection signal, improving the accuracy of overcurrent detection. Simultaneously, by converting the voltage of the first or second comparison result signal through the switch module 220, the output overcurrent detection signal can be better adapted to the driving requirements of the intelligent power module 200, effectively solving the problem of false tripping of the overcurrent protection of the intelligent power module 200.

[0080] In some embodiments of this application, the overcurrent detection circuit 100 further includes a filtering module 30. The filtering module 30 is connected to the signal processing module 20 and is used to filter the overcurrent detection signal to obtain a filtered overcurrent detection signal. The filtering module 30 is also used to connect to the intelligent power module 200 and send the filtered overcurrent detection signal to the intelligent power module 200.

[0081] In this embodiment, the overcurrent detection signal is filtered by the filtering module 30, ensuring that the filtered signal is free of noise and improving signal quality. This allows the filtered overcurrent detection signal to be transmitted to the intelligent power module 200 more stably and accurately. Furthermore, the intelligent power module 200 can more accurately adjust its operating state based on the filtered overcurrent detection signal, such as operating normally or shutting down the output, to prevent equipment damage or safety accidents, effectively solving the problem of malfunctioning overcurrent protection in the intelligent power module 200.

[0082] Please see Figure 3 and Figure 4 In some embodiments of this application, the comparison module 210 includes a comparator 211. The inverting input of the comparator 211 is connected to the sampling module 10 and is used to acquire the bus detection signal Vb, while the non-inverting input of the comparator 211 is used to acquire the reference voltage signal Va.

[0083] Comparator 211 is used to output a first comparison result signal when the bus detection signal Vb is less than the reference voltage signal Va. Alternatively, comparator 211 is also used to output a second comparison result signal when the bus detection signal Vb is greater than the reference voltage signal Va.

[0084] In this embodiment, comparator 211 compares the bus detection signal Vb at the inverting input terminal with the reference voltage signal Va at the non-inverting input terminal, and outputs a first comparison result signal or a second comparison result signal. When the bus detection signal Vb is less than the reference voltage signal Va, the first comparison result signal output by comparator 211 is a high-level signal. When the bus detection signal Vb is greater than the reference voltage signal Va, the second comparison result signal output by comparator 211 is a low-level signal. Comparator 211 can quickly and accurately compare the bus detection signal Vb at the inverting input terminal with the reference voltage signal Va at the non-inverting input terminal, avoiding output jitter caused by small fluctuations in the input signal, enhancing anti-interference capability, and avoiding inter-signal interference.

[0085] Please see Figure 4 In some embodiments of this application, the comparison module 210 further includes a reference conversion module 212. A first terminal of the reference conversion module 212 is used to acquire the control-side voltage signal ITRIP_TEST. A second terminal of the reference conversion module 212 is used to acquire a first voltage signal VCC. A third terminal of the reference conversion module 212 outputs a reference voltage signal Va to the non-inverting input of the comparator 211. The reference conversion module 212 is used to perform voltage conversion on the control-side voltage signal ITRIP_TEST to obtain the reference voltage signal Va.

[0086] In this embodiment, the reference voltage signal Va serves as the input signal to the non-inverting input of comparator 211 and also as the reference point. The control-side voltage signal ITRIP_TEST can be set by the MCU and converted by the reference conversion module 212 to be set into different reference voltage signals Va, thereby setting different overcurrent points. The reference conversion module 212 converts the control-side voltage signal ITRIP_TEST to match the non-inverting input of comparator 211, ensuring that comparator 211 can accurately and reliably complete the comparison judgment. Furthermore, the reference conversion module 212 isolates the control-side voltage signal ITRIP_TEST from the reference voltage signal Va input to the non-inverting input of comparator 211, providing safety protection and interference suppression, thereby preventing MCU-side noise from interfering with the non-inverting input signal of comparator 211.

[0087] In some embodiments of this application, the reference conversion module 212 includes a first resistor 2121, a second resistor 2122, a third resistor 2123, and a first capacitor 2124. One end of the first resistor 2121 is used to acquire the control-side voltage signal ITRIP_TEST, and the other end of the first resistor 2121 is connected to the non-inverting input of the comparator 211.

[0088] One end of the second resistor 2122 is connected to the non-inverting input of the comparator 211, and the other end of the second resistor 2122 is grounded. One end of the third resistor 2123 is used to acquire the first voltage signal, and the other end of the third resistor 2123 is connected to the non-inverting input of the comparator 211. One end of the first capacitor 2124 is connected to the non-inverting input of the comparator 211, and the other end of the first capacitor 2124 is grounded.

[0089] In this embodiment, the three-phase currents drawn from the negative phase current pins (e.g., NU, NV, and NW pins) of the intelligent power module 200 are sampled by the sampling module 10 and converged to form a bus detection signal Vb, which is then input to the inverting input of comparator 211. The reference voltage signal Va at the non-inverting input of comparator 211 serves as the reference voltage. Through the first resistor 2121, the second resistor 2122, and the third resistor 2123, the control-side voltage signal ITRIP_TEST can be voltage-converted to obtain the reference voltage signal Va, which is then input to the non-inverting input of comparator 211 and compared with the bus detection signal Vb.

[0090] The voltage of the control-side voltage signal ITRIP_TEST is V. TEST The reference voltage signal Va, after being converted by the first resistor 2121, the second resistor 2122, and the third resistor 2123, is input to the non-inverting input of comparator 211. According to Kirchhoff's current law: (V TEST -Va) / R 2121 +(VCC-Va) / R 2123 =Va / R 2122 .

[0091] When the control-side voltage signal ITRIP_TEST is high, i.e., V TEST The voltage is equal to the VCC voltage. Substituting this into the above formula, we can obtain the voltage of the reference voltage signal as:

[0092] Va=(R 2122 *VCC) / (R 2122 +(R 2123 *R 2121 / (R 2123 +R 2121 ))).

[0093] When the control-side voltage signal ITRIP_TEST is low, i.e., V TEST The voltage is equal to 0V. Substituting this into the above formula, we can obtain the voltage of the reference voltage signal as:

[0094] Va=((R 2121 *R 2122 / (R 2121 +R 2122))*VCC) / ((R 2121 *R 2122 / (R 2121 +R 2122 ))+R 2123 ).

[0095] Furthermore, by setting the resistance values ​​of the first resistor 2121, the second resistor 2122, and the third resistor 2123 in the reference conversion module 212, the reference voltage signal Va can be adjusted according to the control-side voltage signal ITRIP_TEST to set different overcurrent points, adapt to different application scenarios, and accommodate different reference voltage signals. Furthermore, the first capacitor 2124 filters out noise, stabilizes the reference voltage signal at the non-inverting input of the comparator 211, suppresses output signal jitter of the comparator 211, achieves signal isolation, and enhances safety protection and interference suppression.

[0096] Please see Figure 5 and Figure 6 In some embodiments of this application, the switching module 220 includes a P-type transistor. The first terminal of the P-type transistor is connected to the output terminal of the comparison module 210, and is used to acquire a first comparison result signal or a second comparison result signal. The second terminal of the P-type transistor is used to acquire a first voltage signal VCC. The third terminal of the P-type transistor is used to output an overcurrent detection signal ITRIP. The P-type transistor is either a P-type bipolar transistor 2211 or a P-type field-effect transistor 2222.

[0097] In this embodiment, the P-type transistor is used as a switching transistor. It can be a P-type bipolar transistor 2211, or it can be understood as a PNP transistor, such as... Figure 5 As shown. A P-type transistor can be a P-type field-effect transistor 2222, or it can be understood as a P-type MOSFET, such as... Figure 6 As shown.

[0098] The first terminal of the P-type transistor is connected to the output terminal of the comparator module 210, i.e., to the output terminal of the comparator 211, to obtain either the first comparison result signal or the second comparison result signal. When the bus detection signal Vb is less than the reference voltage signal Va, the first comparison result signal output by the comparator 211 is a high-level signal, causing the P-type transistor to not conduct. The overcurrent detection signal ITRIP output by the third terminal of the P-type transistor is a low-level signal and is transmitted to the detection pin (e.g., the CSC pin) of the intelligent power module 200. At this time, the overcurrent detection signal ITRIP detected by the detection pin (e.g., the CSC pin) of the intelligent power module 200 is a low-level signal less than the set threshold voltage, allowing the intelligent power module 200 to operate normally, thereby maintaining the normal output of the U-phase, V-phase, and W-phase of the intelligent power module 200.

[0099] When the bus detection signal Vb is greater than the reference voltage signal Va, the second comparison result signal output by comparator 211 is a low-level signal, causing the P-type transistor to conduct. Since the second terminal of the P-type transistor receives the first voltage signal VCC, when the P-type transistor is conducting, the overcurrent detection signal ITRIP output by the third terminal of the P-type transistor is a high-level signal and is transmitted to the detection pin (e.g., CSC pin) of the intelligent power module 200. At this time, the overcurrent detection signal ITRIP detected by the detection pin (e.g., CSC pin) of the intelligent power module 200 is a high-level signal greater than the set threshold voltage, causing the overcurrent protection function inside the intelligent power module 200 to be triggered, shutting down the three-phase output of U-phase, V-phase, and W-phase, and simultaneously outputting a fault signal to the MCU through the fault signal output pin (e.g., FO pin) of the intelligent power module 200 to perform the corresponding alarm mechanism.

[0100] Therefore, through the comparator 211 and the P-type transistor in the comparison module 210, overcurrent detection is indirectly achieved. This effectively isolates the acquired three-phase current signal from the overcurrent detection signal, achieving isolation between different signal ports of the intelligent power module 200. It avoids interference signals generated by direct sampling of the three-phase current by resistors in traditional circuits, filters out noise interference, and improves the accuracy of overcurrent detection. Thus, the overcurrent detection circuit 100 provided in this application solves the problem of low overcurrent detection accuracy in traditional circuits and effectively prevents malfunctions of the overcurrent protection in the intelligent power module 200.

[0101] In some embodiments of this application, when the P-type transistor is a P-type bipolar transistor 2211, the base terminal of the P-type bipolar transistor 2211 is connected to the output terminal of the comparator 211 to obtain a first comparison result signal or a second comparison result signal. The emitter terminal of the P-type bipolar transistor 2211 obtains a first voltage signal VCC. The collector terminal of the P-type bipolar transistor 2211 outputs an overcurrent detection signal ITRIP.

[0102] In some embodiments of this application, when the P-type transistor is a P-type field-effect transistor 2222, the gate terminal of the P-type field-effect transistor 2222 is connected to the output terminal of the comparator 211 to obtain a first comparison result signal or a second comparison result signal. The source terminal of the P-type field-effect transistor 2222 obtains a first voltage signal VCC. The drain terminal of the P-type field-effect transistor 2222 outputs an overcurrent detection signal ITRIP.

[0103] In some embodiments of this application, the switch module 220 further includes a fourth resistor 222 and a fifth resistor 223. One end of the fourth resistor 222 is connected to the third terminal of the P-type transistor, and the other end of the fourth resistor 222 outputs an overcurrent detection signal. One end of the fifth resistor 223 is connected to the other end of the fourth resistor 222, and the other end of the fifth resistor 223 is grounded.

[0104] In this embodiment, one end of the fourth resistor 222 is connected to the third end of the P-type transistor. Alternatively, one end of the fourth resistor 222 can be understood as being connected to the collector end of the P-type bipolar transistor 2211, or one end of the fourth resistor 222 can be connected to the drain end of the P-type field-effect transistor 2222.

[0105] When the P-type bipolar transistor 2211 or the P-type field-effect transistor 2222 is not conducting, the common terminal of the fourth resistor 222 and the fifth resistor 223 is grounded through the fifth resistor 223. Therefore, the overcurrent detection signal ITRIP is a low-level signal, which can also be understood as 0 voltage.

[0106] When the P-type bipolar transistor 2211 or the P-type field-effect transistor 2222 is turned on, the first voltage signal VCC is grounded through the P-type bipolar transistor 2211 or the P-type field-effect transistor 2222, the fourth resistor 222, and the fifth resistor 223. Therefore, the overcurrent detection signal ITRIP is a high-level signal, which can also be understood as the voltage across the fifth resistor 223 after the first voltage signal VCC is divided by the fourth resistor 222 and the fifth resistor 223.

[0107] The fourth resistor 222 and the fifth resistor 223 convert the current flowing through the P-type bipolar transistor 2211 or the P-type field-effect transistor 2222 into a voltage signal, limiting the current magnitude and protecting the P-type bipolar transistor 2211 or the P-type field-effect transistor 2222, as well as the downstream intelligent power module 200, from damage due to excessive current. Furthermore, the fourth resistor 222 and the fifth resistor 223 can also convert the current flowing through the P-type bipolar transistor 2211 or the P-type field-effect transistor 2222 into a voltage signal matching the detection pin of the intelligent power module 200, achieving more accurate overcurrent detection.

[0108] Please see Figure 7 In some embodiments of this application, the filtering module 30 includes a sixth resistor 310 and a second capacitor 320. One end of the sixth resistor 310 is connected to the signal processing module 20 for acquiring an overcurrent detection signal, and the other end of the sixth resistor 310 is connected to the detection pin of the intelligent power module 200. One end of the second capacitor 320 is connected to the other end of the sixth resistor 310 and the detection pin of the intelligent power module 200, and the other end of the second capacitor 320 is grounded.

[0109] In this embodiment, the sixth resistor 310 and the second capacitor 320 form an RC filter circuit, which filters the overcurrent detection signal ITRIP and outputs it to the detection pin of the intelligent power module 200, such as the CSC pin. Furthermore, the signal filtered by the RC filter circuit formed by the sixth resistor 310 and the second capacitor 320 is free of noise and is more stable and continuous, which facilitates more accurate detection by the detection pin of the intelligent power module 200. This allows the intelligent power module 200 to more accurately adjust its operating state, such as normal operation or output shutdown, to avoid equipment damage or safety accidents, effectively solving the problem of false overcurrent protection of the intelligent power module 200.

[0110] Please see Figure 8 In some embodiments of this application, the sampling module 10 includes a seventh resistor 111, an eighth resistor 112, a ninth resistor 121, a tenth resistor 122, an eleventh resistor 131, a twelfth resistor 132, and a third capacitor 140. One end of the seventh resistor 111 is connected to the first phase current negative terminal pin of the intelligent power module 200 (e.g., ...). Figure 8 The seventh resistor 111 is connected to the NU pin, and the other end of the seventh resistor 111 is grounded. One end of the eighth resistor 112 is connected to one end of the seventh resistor 111, and the other end of the eighth resistor 112 is connected to the signal processing module 20.

[0111] One end of the ninth resistor 121 is connected to the negative pin of the second phase current of the intelligent power module 200 (e.g., Figure 8 One end of the ninth resistor 121 is connected to the NV pin of the intelligent power module 200, and the other end of the ninth resistor 121 is grounded. One end of the tenth resistor 122 is connected to one end of the ninth resistor 121, and the other end of the tenth resistor 122 is connected to the other end of the eighth resistor 112. One end of the eleventh resistor 131 is connected to the third phase current negative pin of the intelligent power module 200 (e.g., the NV pin). Figure 8 Connect the NW pin to the eleventh resistor 131, and ground the other end of the eleventh resistor 131.

[0112] One end of the twelfth resistor 132 is connected to one end of the eleventh resistor 131, and the other end of the twelfth resistor 132 is connected to the other end of the eighth resistor 112. One end of the third capacitor 140 is connected to the other end of the eighth resistor 112, and the other end of the third capacitor 140 is grounded.

[0113] In this embodiment, the first phase current is acquired by connecting the seventh resistor 111 in series between the NU pin of the intelligent power module 200 and ground. Figure 8 The U-phase current corresponds to the NU pin. The first-phase current flows through the seventh resistor 111, generating a voltage drop. The second-phase current is sampled by connecting the ninth resistor 121 in series between the NV pin of the intelligent power module 200 and ground. Figure 8The V-phase current corresponds to the NV pin. The second-phase current flows through the ninth resistor 121, generating a voltage drop. The third-phase current is sampled by connecting the eleventh resistor 131 in series between the NW pin of the intelligent power module 200 and ground. Figure 8 The W-phase current corresponds to the NW pin. The third-phase current flows through the eleventh resistor 131, generating a voltage drop. A three-resistor sampling structure is formed by the seventh resistor 111, the ninth resistor 121, and the eleventh resistor 131.

[0114] One end of the eighth resistor 112, the tenth resistor 122, and the twelfth resistor 132 are connected to one end of the sampling resistor for the three-phase current, and the other end of the eighth resistor 112, the tenth resistor 122, and the twelfth resistor 132 are connected to the third capacitor 140 and grounded. The eighth resistor 112, the tenth resistor 122, the twelfth resistor 132, and the third capacitor 140 form a filter circuit to filter the signal entering the inverting input of the comparator 211.

[0115] Furthermore, based on Ohm's law, the three-phase current of the load is sampled through sampling resistors 111 (seventh resistor), 112 (eighth resistor), 121 (ninth resistor), 122 (tenth resistor), 131 (eleventh resistor), 132 (twelfth resistor), and 140 (third capacitor), and then converged and superimposed to form the bus detection signal Vb, which can reflect the changes in the bus current. Thus, the three-phase current signal is converted into the bus detection signal Vb and connected to the inverting input of comparator 211. In other words, the three-phase current of the load is converted into a voltage signal and connected to the inverting input of comparator 211 to be compared with the reference voltage signal Va at the non-inverting input of comparator 211.

[0116] Therefore, by using the seventh resistor 111, the eighth resistor 112, the ninth resistor 121, the tenth resistor 122, the eleventh resistor 131, the twelfth resistor 132, and the third capacitor 140, the three-phase current of the load during actual operation is aggregated and fed back to the inverting input of comparator 211 in the form of a voltage signal. The principle is simple and the cost is low. Thus, by setting the reference voltage signal Va at the non-inverting input of comparator 211, the bus detection signal Vb is compared with the reference voltage signal Va. Combined with the P-type bipolar transistor 2211 or the P-type field-effect transistor 2222, the purpose of monitoring whether the three-phase current is overcurrent is achieved.

[0117] Please see Figure 9In some embodiments of this application, the fault signal output pin (e.g., the FO pin) of the intelligent power module 200 outputs a fault signal V-FO and sends it to the MCU to trigger a corresponding alarm mechanism. Simultaneously, the fault signal output pin (e.g., the FO pin) of the intelligent power module 200 can also serve as a temperature monitoring pin to monitor the temperature of the intelligent power module 200. The FO pin of the intelligent power module 200 is connected to one end of the thirteenth resistor 300, and the other end of the thirteenth resistor 300 is connected to a +3.3V voltage. The FO pin of the intelligent power module 200 is connected to one end of the fourth capacitor 400, and the other end of the fourth capacitor 400 is grounded. The FO pin of the intelligent power module 200 is connected to one end of the fourteenth resistor 500, and the other end of the fourteenth resistor 500 outputs an IPM-TEMP signal to the MCU to monitor the temperature of the intelligent power module 200, ensuring the stable and safe operation of the intelligent power module 200.

[0118] This application provides a garment processing device, including any of the overcurrent detection circuits 100 described in the above embodiments.

[0119] In this embodiment, the clothing processing equipment can be a washing machine, a drying machine, or a washer-dryer combo that can wash and dry clothes. The clothing processing equipment can be installed directly on the floor or a tabletop, or it can be wall-mounted or countertop.

[0120] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0121] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0122] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0123] In the embodiments provided in this application, it should be understood that the disclosed devices / terminal equipment and methods can be implemented in other ways. For example, the device / terminal equipment embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling or direct coupling or communication connection may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0124] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0125] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0126] If the integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.

[0127] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. An overcurrent detection circuit, characterized in that, include: The sampling module (10) is connected to the intelligent power module (200) and is used to collect the three-phase current signal provided by the intelligent power module (200) to obtain the bus detection signal; The signal processing module (20) is connected to the sampling module (10) and is used to compare the bus detection signal with the reference voltage signal to obtain a comparison result signal, and to convert the comparison result signal to obtain an overcurrent detection signal. The signal processing module (20) is also connected to the intelligent power module (200) and is used to send the overcurrent detection signal to the intelligent power module (200).

2. The overcurrent detection circuit as described in claim 1, characterized in that, The signal processing module (20) includes: The comparison module (210) is connected to the sampling module (10) and is used to output a first comparison result signal when the bus detection signal is less than the reference voltage signal; Alternatively, the comparison module (210) is also used to output a second comparison result signal when the bus detection signal is greater than the reference voltage signal.

3. The overcurrent detection circuit as described in claim 2, characterized in that, The signal processing module (20) further includes: The switch module (220), connected to the comparison module (210), is used to cut off the signal based on the first comparison result signal or to turn on the signal based on the second comparison result signal, and output the overcurrent detection signal.

4. The overcurrent detection circuit as described in claim 1, characterized in that, The overcurrent detection circuit further includes: The filtering module (30) is connected to the signal processing module (20) and is used to filter the overcurrent detection signal to obtain the filtered overcurrent detection signal. The filtering module (30) is also connected to the intelligent power module (200) and sends the filtered overcurrent detection signal to the intelligent power module (200).

5. The overcurrent detection circuit as described in claim 2, characterized in that, The comparison module (210) includes: Comparator (211), the inverting input terminal of the comparator (211) is connected to the sampling module (10) for acquiring the bus detection signal, and the non-inverting input terminal of the comparator (211) is used to acquire the reference voltage signal; The comparator (211) is used to output the first comparison result signal when the bus detection signal is less than the reference voltage signal; Alternatively, the comparator (211) may also be used to output the second comparison result signal when the bus detection signal is greater than the reference voltage signal.

6. The overcurrent detection circuit as described in claim 5, characterized in that, The comparison module (210) further includes: A reference conversion module (212) is provided, wherein the first terminal of the reference conversion module (212) is used to acquire the control side voltage signal, the second terminal of the reference conversion module (212) is used to acquire the first voltage signal, and the third terminal of the reference conversion module (212) outputs the reference voltage signal to the non-inverting input terminal of the comparator (211). The reference conversion module (212) is used to perform voltage conversion on the control side voltage signal to obtain the reference voltage signal.

7. The overcurrent detection circuit as described in claim 6, characterized in that, The reference conversion module (212) includes: A first resistor (2121) is used to acquire the control side voltage signal at one end, and the other end of the first resistor (2121) is connected to the non-inverting input terminal of the comparator (211). The second resistor (2122) has one end connected to the non-inverting input of the comparator (211), and the other end grounded. A third resistor (2123) is used to acquire the first voltage signal at one end, and the other end of the third resistor (2123) is connected to the non-inverting input terminal of the comparator (211). The first capacitor (2124) has one end connected to the non-inverting input of the comparator (211), and the other end grounded.

8. The overcurrent detection circuit as described in claim 3, characterized in that, The switching module (220) includes: The P-type transistor has a first terminal connected to the output terminal of the comparison module (210) for acquiring the first comparison result signal or the second comparison result signal, a second terminal for acquiring the first voltage signal, and a third terminal for outputting the overcurrent detection signal. The P-type transistor is either a P-type bipolar transistor (2211) or a P-type field-effect transistor (2222).

9. The overcurrent detection circuit as described in claim 8, characterized in that, The switching module (220) also includes: A fourth resistor (222) is provided, one end of which is connected to the third terminal of the P-type transistor, and the other end of which outputs the overcurrent detection signal. The fifth resistor (223) has one end connected to the other end of the fourth resistor (222), and the other end of the fifth resistor (223) is grounded.

10. The overcurrent detection circuit as described in claim 4, characterized in that, The filtering module (30) includes: A sixth resistor (310) is provided, one end of which is connected to the signal processing module (20) to acquire the overcurrent detection signal, and the other end of which is connected to the detection pin of the intelligent power module (200). The second capacitor (320) has one end connected to the other end of the sixth resistor (310) and the detection pin of the intelligent power module (200), and the other end of the second capacitor (320) is grounded.

11. The overcurrent detection circuit as described in any one of claims 1 to 10, characterized in that, The sampling module (10) includes: The seventh resistor (111) has one end connected to the negative terminal pin of the first phase current of the intelligent power module (200), and the other end of the seventh resistor (111) is grounded. The eighth resistor (112) is connected at one end to one end of the seventh resistor (111) and at the other end to the signal processing module (20). The ninth resistor (121) has one end connected to the negative terminal pin of the second phase current of the intelligent power module (200), and the other end of the ninth resistor (121) is grounded. The tenth resistor (122) has one end connected to one end of the ninth resistor (121) and the other end connected to the other end of the eighth resistor (112). The eleventh resistor (131) has one end connected to the negative terminal pin of the third phase current of the intelligent power module (200), and the other end of the eleventh resistor (131) is grounded. The twelfth resistor (132) has one end connected to one end of the eleventh resistor (131) and the other end connected to the other end of the eighth resistor (112). A third capacitor (140) is connected at one end to the other end of the eighth resistor (112), and the other end of the third capacitor (140) is grounded.

12. The overcurrent detection circuit as described in claim 1, characterized in that, The intelligent power module (200) is connected to the load and is used to control the operating state of the load according to the overcurrent detection signal.

13. A garment processing device, characterized in that, Includes the overcurrent detection circuit according to any one of claims 1 to 12.

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