CN118250853A

CN118250853A - Load identification circuit, load identification method and household appliance

Info

Publication number: CN118250853A
Application number: CN202211659075.1A
Authority: CN
Inventors: 曾锋; 张由之; 甘章泽; 王志锋; 曾宪光; 邵天永; 陈志强
Original assignee: Foshan Shunde Midea Electrical Heating Appliances Manufacturing Co Ltd
Current assignee: Foshan Shunde Midea Electrical Heating Appliances Manufacturing Co Ltd
Priority date: 2022-12-22
Filing date: 2022-12-22
Publication date: 2024-06-25

Abstract

The application discloses a load identification circuit, a load identification method and household equipment, wherein the circuit comprises the following components: the device comprises a rectifying unit, a control unit, a heating unit and a reversing unit, wherein the rectifying unit is used for rectifying high-level current or low-level current; the heating unit is electrically connected with the rectifying unit and comprises two independent resonant heating loops which are respectively connected with the control port of the control unit and receive the control signal of the control unit; the reversing unit is respectively and electrically connected with the heating unit and the receiving port of the control unit and transmits reversing signals to the control unit; the control unit is also used for acquiring the reversing time length and the frequency time length table according to the reversing signal, acquiring the material corresponding to the reversing time length and adjusting the heating power of the heating unit. Not only can the anti-interference performance of the load identification circuit be improved, but also the accuracy of the load identification circuit can be improved.

Description

Load identification circuit, load identification method and household appliance

Technical Field

The present application relates to the technical field of circuit control, and more particularly, to a load identification circuit, a load identification method, and a home appliance.

Background

The household induction heating equipment can judge the material of a heated appliance (such as a pot) before heating, detect the current turnover times by charging the coil panel and the capacitor, and then judge the material of the heated appliance according to the current turnover times, namely judge whether the material of the heated appliance is iron or medical stone and other materials. In the detection process, the coil panel is in a natural discharge state, so that the coil panel is very easy to be interfered by an external magnetic field, and the coil panel can absorb the interference energy and can influence the accuracy of identifying the material of the heated appliance.

Disclosure of Invention

In view of the above, the present invention proposes a load recognition circuit, a load recognition method, and a home appliance to improve the above.

In a first aspect, an embodiment of the present application provides a load identification circuit, including: the rectification unit is used for rectifying high-level current or low-level current; the control unit comprises an input port, a control port, a receiving port and an output port, wherein the input port is used for receiving a load identification instruction, and the output port is used for feeding back a load identification result; the heating unit is electrically connected with the rectifying unit and comprises two groups of independent resonant heating loops, the two groups of independent resonant heating loops are respectively connected with the control port of the control unit and receive control signals of the control unit, when the rectifying unit inputs rectified high-level current to the heating unit, the control signals control one group of resonant heating loops to be communicated, and when the rectifying unit inputs rectified low-level current to the heating unit, the control signals control the other group of resonant heating loops to be communicated; the reversing unit is respectively and electrically connected with the heating unit and the receiving port of the control unit and transmits reversing signals to the control unit; the control unit is further configured to obtain a commutation duration according to the commutation signal, search a frequency duration table according to the commutation duration, obtain a material corresponding to the commutation duration, and adjust heating power of the heating unit, where the frequency duration table includes heating frequencies and commutation durations corresponding to multiple load materials.

In a second aspect, an embodiment of the present application further provides a load identification method, where the method is used in the load identification circuit described in the first aspect, and the method includes: based on the load identification instruction, acquiring a reversing signal of a reversing unit; based on the reversing signal, acquiring a reversing time length corresponding to the reversing signal; searching a frequency duration table according to the reversing duration, and obtaining a material corresponding to the reversing duration; and if the commutation time length is smaller than or equal to the preset commutation time length, operating with the current circuit power.

In a third aspect, an embodiment of the present application further provides a home appliance, including: the device body and the load identification circuit according to the first aspect, wherein the load identification circuit is disposed on the device body.

The load identification circuit provided by the scheme of the application comprises: the control unit is used for controlling the communication of the heating unit, the heating unit can be prevented from being in a discharge state for a long time and being interfered by an external magnetic field, the control unit is used for receiving reversing signals of the reversing unit, the reversing unit is used for analyzing the reversing signals to obtain reversing time length, and the obtained reversing time length is compared with a pre-stored frequency time length table to obtain materials corresponding to the reversing time length, so that the anti-interference performance of the load identification circuit can be improved, and the accuracy of the load identification circuit can be improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required for the description of the embodiments will be briefly introduced below, and it is apparent that the drawings in the following description are only some embodiments of the present application, not all embodiments. All other embodiments and figures obtained by a person skilled in the art without any inventive effort are within the scope of protection of the present application based on the embodiments of the present application.

Fig. 1 is a schematic diagram of a load identification circuit according to an embodiment of the application.

Fig. 2 is a schematic diagram showing a structure of a load identification circuit according to an exemplary embodiment of the present application.

Fig. 3 is a schematic diagram of a load identification circuit according to another embodiment of the present application.

Fig. 4 is a schematic diagram showing a structure of a load identification circuit according to another exemplary embodiment of the present application.

Fig. 5 shows a flowchart of a load identification method according to an embodiment of the present application.

Fig. 6 shows a block diagram of a home appliance provided by an embodiment of the present application.

Detailed Description

In order to enable those skilled in the art to better understand the present application, the following description will make clear and complete descriptions of the technical solutions according to the embodiments of the present application with reference to the accompanying drawings.

The existing induction heating cooking utensil can carry out pot to have no detection before heating, and part adopts to turn on IGBT (insulated gate bipolar transistor) switch for a period of fixed time to charge wire coil and electric capacity, then turns off IGBT, through detecting current upset number of times to judge pot to have or have nothing. At this time, the wire coil is in a natural discharge state, is very easy to be interfered by an external magnetic field, absorbs the energy of the interference, and can cause failure in detecting the cookware or misjudgment of no cookware as the cookware. In addition, when a plurality of jambs work mutually, other jambs working need to be stopped, so that interference of jamb heating on jambs is avoided, user experience is influenced, and further on a hardware circuit, a current transformer is often required to collect a current detection circuit, and cost is increased.

The inventor proposes the load identification circuit, the load identification method and the household equipment provided by the application, wherein the load identification circuit comprises a rectifying unit, and the rectifying unit is used for rectifying high-level current or low-level current; the control unit comprises an input port, a control port, a receiving port and an output port, wherein the input port is used for receiving a load identification instruction, and the output port is used for feeding back a load identification result; the heating unit is electrically connected with the rectifying unit and comprises two groups of independent resonant heating loops, the two groups of independent resonant heating loops are respectively connected with the control port of the control unit and receive control signals of the control unit, when the rectifying unit inputs rectified high-level current to the heating unit, the control signals control one group of resonant heating loops to be communicated, and when the rectifying unit inputs rectified low-level current to the heating unit, the control signals control the other group of resonant heating loops to be communicated; the reversing unit is respectively and electrically connected with the heating unit and the receiving port of the control unit and transmits reversing signals to the control unit; the control unit is further configured to obtain a commutation duration according to the commutation signal, search a frequency duration table according to the commutation duration, obtain a material corresponding to the commutation duration, and adjust heating power of the heating unit, where the frequency duration table includes heating frequencies and commutation durations corresponding to multiple load materials. The control unit is used for controlling the communication of the heating unit, so that the heating unit can be prevented from being in a discharge state for a long time and being interfered by an external magnetic field, the control unit also receives a reversing signal of the reversing unit, the reversing unit analyzes the reversing signal to obtain reversing time length, and the reversing time length is compared with a pre-stored frequency time length table to obtain a material corresponding to the reversing time length, so that the anti-interference performance of the load identification circuit can be improved, and the accuracy of the load identification circuit can be improved.

The load identification circuit provided by the embodiment of the application will be described in detail through specific embodiments.

Referring to fig. 1, an embodiment of the present application provides a load identification circuit 100, where the load identification circuit 100 includes: a control unit 110, a heating unit 120, a commutation unit 130, and a rectification unit 140. The control unit 110 is electrically connected to the heating unit 120, the rectifying unit 140 is electrically connected to the heating unit, and the reversing unit 130 is electrically connected to the control unit 110 and the heating unit 120, respectively.

In the embodiment of the present application, the control unit 110 is used for controlling the communication of the heating unit 120 and for analyzing and processing the signal transmitted by the steering unit 130. The control unit 110 may include an input port (not shown in the drawing), which is used to receive a load identification instruction, a control port 110a, a receiving port 110b, and an output port (not shown in the drawing), which is used to feed back a load identification result.

In one embodiment, the control unit 110 may include an integrated circuit chip, which uses a single chip microcomputer as an example, and adopts a very large scale integrated circuit technology to integrate functions such as a central processing unit (central processing unit, abbreviated as CPU) with data processing capability, a random access memory, a read-only memory, various interrupt systems, a timer/counter, and a transmitter into a small and perfect microcomputer system formed by a single silicon chip. The input port of the control unit 110 receives a command signal from a user, and is electrically connected to the control port 110a through a transmitter, so as to transmit the control signal, so that the circuit operates according to the command signal from the user.

Alternatively, the integrated circuit chip may be an STM32 single chip microcomputer, or may be an integrated circuit chip such as a 51 single chip microcomputer, which may be specifically selected according to actual needs, which is not limited by the present application.

In another embodiment, the control unit 110 may also be a programmable logic controller (Programmable Logic Controller, abbreviated as PLC), which is a digital electronic device with a microprocessor, and is used for automatic control, and can load control instructions into the memory at any time for storage and execution. The programmable controller is composed of an internal CPU, an instruction and data memory, an input/output unit, a power module, a digital analog unit and the like. The user transmits an instruction signal through the PLC, and the instruction signal is transmitted to a control port of the control unit 110 at a transmission port of the PLC.

In an embodiment of the present application, as shown in fig. 1, the heating unit 120 includes at least two sets of resonant heating circuits, and the at least two sets of independent resonant heating circuits are respectively connected to the control port 110a of the control unit 110.

The heating unit 120 may include a coil disc having a large resistance value. The coil disk is heated by the action of the current, so that the object placed on the coil disk is heated. The heating unit 120 may further include a resonant heating unit composed of a capacitor and a coil. The scheme of the application is preferably a resonance heating unit consisting of a capacitor and a coil.

Referring specifically to fig. 1, the heating unit 120 may include a first IGBT tube 121, a second IGBT tube 122, a coil disc 123, a first capacitor 124, and a second capacitor 125.

The IGBT is a compound full-control voltage-driven power semiconductor device consisting of a bipolar triode and an insulated gate field effect transistor.

The first IGBT tube 121 includes a first port 121a, a second port 121b, and a third port 121c. The first port 121a of the first IGBT tube 121 is connected to the control port 110a of the control unit 110, and the second port 121b of the first IGBT tube 121 is connected to the rectifying unit 140.

The second IGBT tube 122 includes a first port 122a, a second port 122b, and a third port 122c. The first port 122a of the second IGBT tube 122 is connected to the control port 110a of the control unit 110. The third port 122c of the second IGBT tube 122 is connected to the rectifying unit 140.

The coil disk 123 includes a first port 123a and a second port 123b. The third port 121c of the first IGBT tube 121 is connected to the first port 123a of the coil disc 123. The first port 123a of the coil disc 123 is connected to the second port 122b of the second IGBT tube 122.

The first capacitor 124 includes a first port 124a and a second port 124b. The first port 124a of the first capacitor 124 is connected to the rectifying unit 140, and the second port 124b of the first capacitor 124 is connected to the second port 123b of the coil disc 123.

The second capacitor 125 includes a first port 125a and a second port 125b. The second port 123b of the coil disc 123 is connected to the first port 125a of the second capacitor 125, and the second port 125b of the second capacitor 125 is connected to the rectifying unit 140.

The first IGBT tube 121, the coil panel 123, and the first capacitor 124 are connected in series to form a first group of resonant heating circuit, and the second IGBT tube 122, the coil panel 123, and the second capacitor 125 form a second group of resonant heating circuit. The control unit 110 controls on or off of the IGBT tube of each resonant heating circuit by a control signal to independently control the plurality of resonant heating circuits to heat.

In an embodiment of the present application, the reversing unit 130 is configured to receive the voltage reversing signal in the heating unit 120 and transmit the voltage reversing signal to the control unit 110.

The reversing unit 130 is connected to the heating unit 120 and the receiving port 110b of the control unit 110, respectively. The commutation unit 130 transmits a commutation signal to the control unit 110, and the control unit 110 determines whether the load exists according to the commutation signal.

The commutation signal refers to a voltage commutation signal generated by the first capacitor 124 and the second capacitor 125 in the heating unit 120 under the action of alternating current.

In some embodiments, the reversing unit 130 may include: the first resistor 131 and the detection commutation unit 132.

The first resistor 131 may include a first port 131a and a second port 131b. The detection commutation unit 132 may include a first port 132a, a second port 132b, and a third port 132c. The first port 131a of the first resistor 131 is connected to the second port 124b of the first capacitor 124 and the first port 125a of the second capacitor 125, and the second port 131b of the first resistor 131 is connected to the second port 123b of the coil disc 123. The first port 132a of the detecting and reversing unit 132 is connected to the first port 131a of the first resistor 131, the second port 132b of the detecting and reversing unit 132 is connected to the second port 131b of the first resistor 131, the third port 132c of the detecting and reversing unit 132 is connected to the receiving port 110b of the control unit 110, and the detecting and reversing unit 132 is configured to detect the voltage directions at two ends of the first resistor 131.

The rectifying unit 140 may be a full bridge rectifier or an inverter. The rectifying unit 140 may rectify the ac power outputted from the ac power source and provide the rectified ac power to the heating unit 120.

The rectifying unit 140 may include a first port 140a and a second port 140b. In this embodiment, the first port 140a of the rectifying unit 140 is connected to the second port 121b of the first IGBT tube 121 and the first port 124a of the first capacitor 124, to supply current to the first set of independent resonant heating circuits and the second set of independent resonant heating circuits, and the second port 140b of the rectifying unit 140 is connected to the second port 125b of the second capacitor 125 and the third port 122c of the second IGBT tube 122, to form a complete current loop. The control signal controls the first set of independent resonant heating circuits to be communicated when the rectifying unit 140 inputs the rectified high-level current to the first set of independent resonant heating circuits, and controls the second set of independent resonant heating circuits to be communicated when the rectifying unit inputs the rectified low-level current to the second set of independent resonant heating circuits.

The detecting commutation unit 132 may be a voltage comparator or a device provided with ADC value software for detecting the voltage across the first resistor 131.

In the actual use process, when the control unit 110 controls the IGBT tubes in the first set of independent resonant heating circuits and the second set of independent resonant heating circuits to be alternately connected, alternating currents are generated on the coil disc 123 connected with the IGBT tubes, and the voltage direction of the first resistor 131 connected in series with the coil disc 123 is also alternately changed while the currents alternately flow.

After the control unit 110 processes the obtained voltage commutation signal of the first resistor 131, the voltage commutation signal is processed, and a commutation duration corresponding to the voltage commutation signal is obtained. The control unit 110 compares the commutation duration with a frequency duration table to obtain a load material corresponding to the commutation duration in the frequency duration table, where the frequency duration table includes heating frequencies and commutation durations corresponding to multiple load materials, so as to determine a material corresponding to a load on the coil panel 123, and outputs a determination result through an output port.

According to the load identification circuit provided by the embodiment, the control unit is used for controlling the communication of the heating unit, so that the heating unit is prevented from being in a discharge state for a long time and being interfered by an external magnetic field, the control unit is used for receiving a reversing signal of the reversing unit, the reversing unit is used for analyzing the reversing signal to obtain reversing time, and the obtained reversing time is compared with a pre-stored frequency time table to obtain a material corresponding to the reversing time, so that the anti-interference performance of the load identification circuit can be improved, and the accuracy of the load identification circuit can be improved.

Referring to fig. 2, fig. 2 is a schematic diagram of a load identification circuit according to an exemplary embodiment of the application.

The rectifying unit 140 further includes two input terminals, L1 and N1, respectively. In one ac cycle, when the high-level current is input to the input terminal L1, the rectifying unit 140 rectifies the high-level current, and flows the rectified current to the first IGBT tube 121 of the heating unit 120, the control unit 110 controls the first IGBT tube 121 to be connected in series, the first IGBT tube 121 is connected in series with the coil disc 123, the first resistor 131, and the second capacitor 125, and the high-level current sequentially flows through the first IGBT tube 121 and the coil disc 123, the first resistor 131, and the second capacitor 125, and returns to the rectifying unit 140.

When the low level current is input to the input terminal N1, the rectified current flows to the first capacitor 124, the first resistor 131 and the coil panel 123 in sequence, and when the current flows through the second IGBT tube 122, the control unit 110 controls the second IGBT tube 122 to communicate, and the second IGBT tube 122 is connected to the rectifying unit 140 to form a closed circuit.

The commutation detection unit 132 is connected to two ends of the first resistor 131, and is configured to detect whether the first resistor 131 generates a commutation voltage under the input of different levels, and transmit the detected commutation signal to the control unit 110, where the control unit 110 compares the commutation duration corresponding to the obtained commutation signal with the frequency duration table, so as to determine a material corresponding to the load on the coil disc 123. The inductance and resistance of the coupling between different cookware materials and the coil disc 123 are different, and the commutation duration of the capacitor voltage is also different during heating. If the material corresponding to the load present on the coil disc 123 is good, the resistance of the load coupled to the coil disc 123 becomes large at the same IGBT on time, and thus the voltage commutation time length becomes short.

Referring to fig. 3, fig. 3 illustrates a load identification circuit according to other embodiments of the application. The circuit comprises: the rectifying unit 140, the control unit 110, the heating unit 120, and the reversing unit 130. The rectifying unit 110 is electrically connected to the control unit 110, the control unit 110 is electrically connected to the heating unit 120, and the reversing unit 130 is respectively connected to the control unit 110 and the heating unit 120.

In an embodiment of the present application, the heating unit may include: a first IGBT tube 121, a second IGBT tube 122, a coil bobbin 123, a first capacitor 124, a third IGBT tube 126, and a fourth IGBT tube 127.

The second IGBT tube 122 includes a first port 122a, a second port 122b, and a third port 122c. The first port 122a of the second IGBT tube 122 is connected to the control port 110a of the control unit 110, and the second port 122b of the second IGBT tube 122 is connected to the rectifying unit 140.

The coil disk 123 includes a first port 123a and a second port 123b. The third port 121c of the first IGBT tube 121 is connected to the first port 123a of the coil disc 123.

The first capacitor 124 includes a first port 124a and a second port 124b. The second port 123b of the coil disc 123 is connected to the first port 124a of the first capacitor 124.

The third IGBT tube 126 includes a first port 126a, a second port 126b, and a third port 126c. The first port 126a of the third IGBT tube 126 is connected to the control port 110a of the control unit 110, the second port 126b of the third IGBT tube 126 is connected to the rectifying unit 140, and the third port 126c of the third IGBT tube 126 is connected to the second port 124b of the first capacitor 124.

The fourth IGBT tube 127 includes a first port 127a, a second port 127b, and a third port 127c. The second port 124b of the first capacitor 124 is connected to the second port 127b of the fourth IGBT tube 127. The third port 127c of the fourth IGBT tube 127 is connected to the rectifying unit 140. The first port 127a of the fourth IGBT tube 127 is connected to the control port 110a of the control unit 110.

The rectifying unit 140 may include a first port 140a and a second port 140b. In this embodiment, the first port 140a of the rectifying unit 140 is connected to the second port 121b of the first IGBT tube 121 and the second port 126b of the third IGBT tube 126, to supply current to the first set of independent resonant heating circuits and the second set of independent resonant heating circuits, and the second port 140b of the rectifying unit 140 is connected to the third port 122c of the second IGBT tube 122 and the third port 127c of the fourth IGBT tube 127, to form a complete current loop. The control signal controls the first set of independent resonant heating circuits to be communicated when the rectifying unit 140 inputs the rectified high-level current to the first set of independent resonant heating circuits, and controls the second set of independent resonant heating circuits to be communicated when the rectifying unit inputs the rectified low-level current to the second set of independent resonant heating circuits.

In an embodiment of the application, the reversing unit 130 may include: first resistor 131 and detection reversing unit 132

The first resistor 131 includes a first port 131a and a second port 131b. The first port 131a of the first resistor 131 is connected to the second port 123b of the coil disc 123, and the second port 131b of the first resistor 131 is connected to the first port 124a of the first capacitor 124.

The detection reversing unit 132 includes a first port 132a, a second port 132b, and a third port 132c. The first port 132a of the detecting and reversing unit 132 is connected to the first port 131a of the first resistor 131, the second port 132b of the detecting and reversing unit 132 is connected to the second port 131b of the first resistor 131, the third port 132c of the detecting and reversing unit 132 is connected to the receiving port 110b of the control unit 110, and the detecting and reversing unit 132 is configured to detect the voltage directions at two ends of the first resistor 131.

The embodiment of the application at least comprises 4 IGBT tubes, and each 2 IGBT tubes are respectively connected with the coil panel and the capacitor in series to form an independent resonant heating loop.

Specifically, the control unit in the present embodiment controls the plurality of resonance heating circuits to heat independently by controlling on or off of the IGBT tube of each resonance heating circuit. The plurality of resonant heating circuits may alternately heat or may heat simultaneously. When a plurality of resonant heating circuits alternately heat, the service life of the heating device in the resonant heating circuit can be improved. When a plurality of resonant heating circuits are simultaneously heated, a larger area can be heated at the same time or the time to heat to a predetermined temperature is less. When at least 4 IGBT tubes are arranged in the resonant heating loop, the working pressure of each IGBT tube can be reduced, and the service life of the IGBT tubes is prolonged.

Referring to fig. 4, fig. 4 is a schematic diagram of a load identification circuit according to an exemplary embodiment of the application.

In one ac cycle, when the high-level current is input to the input terminal L1, the rectifying unit 140 rectifies the high-level current, and flows the rectified current to the first IGBT tube 121 and the fourth IGBT tube 127 of the heating unit 120, the control unit 110 controls the first IGBT tube 121 and the fourth IGBT tube 127 to be connected in series, the first IGBT tube 121 is sequentially connected to the first capacitor 124, the first resistor 131, the coil disc 123, and the fourth IGBT tube 127, and the high-level current sequentially flows through the first IGBT tube 121, the first capacitor 124, the first resistor 131, the coil disc 123, and the fourth IGBT tube 127 and returns to the rectifying unit.

When the low-level current is input to the input terminal N1, the rectifying unit 140 rectifies the low-level current, and flows the rectified current to the second IGBT tube 122 and the third IGBT tube 126 of the heating unit 120, the control unit controls the second IGBT tube 122 and the third IGBT tube 126 to be communicated, the third IGBT tube 126 is connected in series with the first capacitor 124, the first resistor 131, the coil disc 123, and the second IGBT tube 122 in order, and the low-level current flows through the third IGBT tube 126, the first capacitor 124, the first resistor 131, the coil disc 123, and the second IGBT tube 122 in order and returns to the rectifying unit 140.

Referring to fig. 5, fig. 5 shows a flow chart of a load identification method according to an embodiment of the present application, which is applied to the load identification circuit, and the load identification method includes: step S210 to step S240.

Step S210: and acquiring a reversing signal of the reversing unit based on the load identification instruction.

The load identification instruction can be an identification instruction obtained through a computer, can be set by a developer in the development process, and can be a load identification instruction which is automatically started by circuit starting. The purpose is to judge whether a load exists on a coil panel or not at the beginning of the connection of a load identification circuit.

The control unit receives a load identification instruction, the heating unit is communicated based on the detection signal, and a capacitor in the heating unit is alternately communicated with the IGBT tube to generate reversing voltage, so that the reversing unit can be connected to the heating unit to acquire a voltage reversing signal of the heating unit.

Step S220: and acquiring the reversing time length corresponding to the reversing signal based on the reversing signal.

And acquiring the reversing time length of the first resistor in one alternating current period according to the reversing signal detected by the reversing unit. The commutation duration refers to a commutation duration obtained by the control unit according to the commutation signal parsing process, and the commutation duration may refer to a commutation duration from when the heating unit receives the high-level current until when the heating unit receives the low-level current, or may refer to a commutation duration when the heating unit switches from the high-level current to the low-level current and switches to the high-level current again, and the commutation duration is not specifically limited herein.

Step S230: and searching a frequency duration table according to the reversing duration, and obtaining a material corresponding to the reversing duration.

The frequency duration table is data pre-stored in a memory of the control unit, and is a corresponding table between heating frequencies and reversing durations established according to various typical materials of the heated appliance.

According to the reversing time length, the material corresponding to the heated appliance can be found in the frequency time length table.

Step S240: and if the commutation time length is smaller than or equal to the preset commutation time length, operating with the current circuit power.

When the circuit is communicated, the IGBT tube works at rated power, and the preset commutation duration refers to the commutation duration corresponding to the commutation signal under the rated power. When the commutation duration is less than or equal to the preset commutation duration, the heated device is heated, and the heated device is not damaged due to the fact that the IGBT current is too large.

In some embodiments, if the commutation period is longer than the preset commutation period, the current circuit power is adjusted until the commutation period is less than or equal to the preset commutation period.

When the commutation time length is longer than the preset commutation time length, the current of the IGBT is overlarge at the moment, and the current circuit power is regulated until the commutation time length is smaller than or equal to the preset commutation time length to protect the heated appliance so as to avoid the heated appliance from being damaged.

The material corresponding to the heated appliance is obtained by comparing the reversing time length and the frequency time length table obtained in the reversing unit, and the power output of the identification circuit can be controlled in real time through the reversing time length, so that the heated appliance is protected, the material of the cooker is identified in real time and the output power is limited in the heating process, and the cost is better.

Referring to fig. 6, the embodiment of the present application further provides a home appliance 200, where the home appliance 200 includes: the device body 210 and the load identification circuit 100 described above, wherein the load identification circuit 100 is disposed on the device body 210.

The household device may be a household device that needs load identification during operation, optionally the household device may include an induction cooker, a cooking machine, and a heating table.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and are not limiting; although the application has been described in detail with reference to the foregoing embodiments, it will be appreciated by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not drive the essence of the corresponding technical solutions to depart from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A load identification circuit, comprising:

the rectification unit is used for rectifying high-level current or low-level current;

the control unit comprises an input port, a control port, a receiving port and an output port, wherein the input port is used for receiving a load identification instruction, and the output port is used for feeding back a load identification result;

The heating unit is electrically connected with the rectifying unit and comprises two groups of independent resonant heating loops, the two groups of independent resonant heating loops are respectively connected with the control port of the control unit and receive control signals of the control unit, when the rectifying unit inputs rectified high-level current to the heating unit, the control signals control one group of resonant heating loops to be communicated, and when the rectifying unit inputs rectified low-level current to the heating unit, the control signals control the other group of resonant heating loops to be communicated; and

The reversing unit is electrically connected with the heating unit and the receiving port of the control unit respectively and transmits reversing signals to the control unit;

The control unit is further configured to obtain a commutation duration according to the commutation signal, search a frequency duration table according to the commutation duration, obtain a material corresponding to the commutation duration, and adjust heating power of the heating unit, where the frequency duration table includes heating frequencies and commutation durations corresponding to multiple load materials.

2. The circuit of claim 1, wherein the heating unit comprises:

the first IGBT tube comprises a first port, a second port and a third port;

the second IGBT tube comprises a first port, a second port and a third port;

the coil panel comprises a first port and a second port;

The first capacitor comprises a first port and a second port;

a second capacitor including a first port and a second port;

The first port of the first IGBT tube is connected with the control port of the control unit, the second port of the first IGBT tube is electrically connected with the rectifying unit, the third port of the first IGBT tube is connected with the first port of the coil panel, the second port of the coil panel is connected with the first port of the second capacitor, the second port of the second capacitor is electrically connected with the rectifying unit to form a first group of resonant heating loop circuits, and when the rectifying unit inputs rectified high-level current to the heating unit, the control signal controls the first group of resonant heating loop circuits to be communicated;

The first port of the second IGBT tube is connected with the control port of the control unit, the first port of the first capacitor is electrically connected with the rectifying unit, the second port of the first capacitor is connected with the second port of the coil panel, the first port of the coil panel is connected with the second port of the second IGBT tube, the third port of the second IGBT tube is electrically connected with the rectifying unit to form a second group of independent resonant heating circuits, and when the rectifying unit inputs rectified low-level current to the heating unit, the control signal controls the second group of resonant heating circuit to be communicated.

3. The circuit of claim 2, wherein the rectifying unit comprises:

The rectification unit comprises a first port and a second port, the first port of the rectification unit is connected with the second port of the first IGBT tube and the first port of the second capacitor, and the second port of the rectification unit is connected with the second port of the second capacitor and the third port of the second IGBT tube to form a complete current loop.

4. A circuit according to claim 2 or 3, wherein the commutation cell comprises:

a first resistor including a first port and a second port;

the detection reversing unit comprises a first port, a second port and a third port, wherein the first port of the first resistor is connected with the first port of the capacitor, the second port of the first resistor is connected with the first port of the coil panel, the first port of the detection reversing unit is connected with the first port of the first resistor, the second port of the detection reversing unit is connected with the second port of the first resistor, the third port of the detection reversing unit is connected with the second port of the control unit, and the detection reversing unit is used for detecting the voltage directions of two ends of the first resistor.

5. The circuit of claim 2, wherein the heating unit further comprises:

The third IGBT tube comprises a first port, a second port and a third port;

the fourth IGBT tube comprises a first port, a second port and a third port;

The first port of the first IGBT tube is connected with the control port of the control unit, the second port of the first IGBT tube is electrically connected with the rectifying unit, the third port of the first IGBT tube is connected with the first port of the coil panel, the second port of the coil panel is connected with the first port of the first capacitor, the second port of the first capacitor is connected with the second port of the fourth IGBT tube, the third port of the fourth IGBT tube is electrically connected with the rectifying unit, the first port of the fourth IGBT tube is connected with the control port of the control unit to form the first group of resonant heating loop circuits, and when the rectifying unit inputs rectified high-level current to the heating unit, the control signal controls the first group of resonant heating loop circuits to be communicated;

The first port of the second IGBT tube is connected with the control port of the control unit, the second port of the second IGBT tube is electrically connected with the rectifying unit, the third port of the second IGBT tube is connected with the second port of the first capacitor, the first port of the first capacitor is connected with the second port of the coil panel, the first port of the coil panel is connected with the second port of the third IGBT tube, the third port of the third IGBT tube is electrically connected with the rectifying unit, the first port of the third IGBT tube is connected with the control port of the control unit to form a second group of independent resonant heating circuits, and when the rectifying unit inputs rectified low-level current to the heating unit, the control signal controls the second group of resonant heating circuit circuits to be communicated.

6. The circuit of claim 5, wherein the rectifying unit comprises:

The rectification unit comprises a first port and a second port, the first port of the rectification unit is connected with the second port of the first IGBT tube and the second port of the second IGBT tube, and the second port of the rectification unit is connected with the third port of the fourth IGBT tube and the third port of the third IGBT tube to form a complete current loop.

7. A circuit according to claim 5 or 6, wherein the commutation cell comprises:

a first resistor including a first port and a second port;

The detection reversing unit comprises a first port, a second port and a third port, wherein the first port of the first resistor is connected with the second port of the capacitor, the second port of the first resistor is connected with the first port of the coil panel, the first port of the detection reversing unit is connected with the first port of the first resistor, the second port of the detection reversing unit is connected with the second port of the first resistor, the third port of the detection reversing unit is connected with the second port of the control unit, and the detection reversing unit is used for detecting the voltage directions of two ends of the first resistor.

8. A load identification method for a load identification circuit as claimed in any one of claims 1 to 7, the method comprising:

based on the load identification instruction, acquiring a reversing signal of a reversing unit;

based on the reversing signal, acquiring a reversing time length corresponding to the reversing signal;

searching a frequency duration table according to the reversing duration, and obtaining a material corresponding to the reversing duration;

And if the commutation time length is smaller than or equal to the preset commutation time length, operating with the current circuit power.

9. The method of claim 8, wherein the searching the frequency duration table according to the commutation duration, after determining the material corresponding to the load, further comprises:

and if the commutation time length is longer than the preset commutation time length, adjusting the current circuit power until the commutation time length is smaller than or equal to the preset commutation time length.

10. A household appliance, comprising:

An apparatus body, and the load identification circuit according to any one of claims 1 to 7, the load identification circuit being provided to the apparatus body.