Cooking equipment
By introducing multiple heating devices and high-frequency AC power conversion technology into the cooking equipment, combined with switching control, the problem of insufficient power in the initial stage of heating is solved, improving cooking efficiency and equipment applicability, and reducing safety risks.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-20
- Publication Date
- 2026-03-10
AI Technical Summary
When heating liquid or solid-liquid mixtures with electricity, the initial heating power is low, which affects cooking efficiency.
It employs multiple heating devices, including electric heating, induction heating, and resistance heating, and converts the input power into high-frequency AC power through a bridge inverter circuit. Combined with a switching device, it controls the heating mode and selects the appropriate heating method for different foods and scenarios.
It improves the applicability and efficiency of cooking equipment, solves the problem of insufficient power in the initial stage of heating, and reduces safety risks and the possibility of corrosion and oxidation of heating electrodes.
Smart Images
Figure CN223979673U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of cooking control, and more particularly to a cooking device. Background Technology
[0002] Electric heating (also known as ohmic heating) is a heating method that directly applies electricity to the object being heated, generating heat based on the object's own resistance. Cooking equipment using electric heating to cook food offers higher heating efficiency compared to traditional methods such as bottom-mounted resistance heating. Furthermore, because there is no heat exchange surface, it prevents food from becoming locally burnt or sticky.
[0003] However, electric heating requires the food itself to generate heat through electrical resistance. If the food being cooked is liquid or a mixture of solid and liquid, the food's low conductivity in the initial heating stage prevents the cooking equipment from using high-power electric heating, thus affecting cooking efficiency. Utility Model Content
[0004] In view of this, embodiments of this application provide a cooking device aimed at improving the cooking efficiency and applicability of cooking devices equipped with an electric heating function.
[0005] The technical solution of this application embodiment is implemented as follows:
[0006] This application embodiment provides a cooking device, the cooking device comprising:
[0007] Pot body;
[0008] A power conversion device for converting the input power of the cooking equipment into a working electrical signal;
[0009] Various heating devices, any type of which, after being supplied with a working electrical signal, are used to heat the food in the pot;
[0010] A switching device, connected to the output terminal of the power conversion device, is used to control one or more of the heating devices to receive a working electrical signal;
[0011] Among them, the multiple heating devices include at least an electrically powered heating device, which includes two sets of heating electrodes. After the heating electrodes are supplied with a working electrical signal, they are used to electrically heat the food in contact with the pot.
[0012] In some embodiments, the heating electrode is disposed on the inner wall of the pot body.
[0013] In some embodiments, the plurality of heating devices further include:
[0014] An induction heating device includes a heating coil, which generates an alternating magnetic field when a working electrical signal is applied to the heating coil, and the pot body is heated under the action of the alternating magnetic field.
[0015] In some embodiments, the plurality of heating devices further include:
[0016] A resistance heating device that generates heat after being supplied with a working electrical signal, comprising at least one of the following: a heating plate, a heating tube, and a heating wire.
[0017] In some embodiments, the cooking apparatus further includes:
[0018] A control device is connected to the power conversion device and the switching device respectively, and is used to control the operation of the power conversion device and the switching device.
[0019] In some implementations, the switching device includes multiple switching modules, each of which is connected to a heating device in a one-to-one correspondence; the switching modules are used to control the power-on state of the corresponding heating devices.
[0020] In some implementations, the operating electrical signal is high-frequency alternating current, and the power conversion device includes a bridge inverter circuit for converting the incoming direct current into high-frequency alternating current. The bridge inverter circuit includes:
[0021] The first bridge arm includes a first upper switch transistor and a first lower switch transistor;
[0022] The second bridge arm includes a second upper switch and a second lower switch;
[0023] The switching device and the various heating devices are connected and positioned between the contacts of the first bridge arm and the second bridge arm, with the contacts positioned between the switching transistors of the bridge arms. The control device includes a drive circuit, which is connected to the drive terminals of each switching transistor of the bridge inverter circuit.
[0024] In some implementations, the bridge inverter circuit further includes:
[0025] The first capacitor is disposed at both ends of the first upper switching transistor;
[0026] The second capacitor is disposed at both ends of the first lower switching transistor;
[0027] The third capacitor is located at both ends of the second upper switching transistor;
[0028] The fourth capacitor is located across the two ends of the second lower switching transistor;
[0029] The fifth capacitor is located at the input terminal of the bridge inverter circuit.
[0030] In some embodiments, the cooking apparatus further includes:
[0031] A first current detection device is installed at the output terminal of the bridge inverter circuit and connected to the control device, used to collect the current of the high-frequency AC power output by the bridge inverter circuit.
[0032] In some embodiments, the cooking apparatus further includes:
[0033] The second current detection device is located at the input end of the bridge inverter circuit and connected to the control device, and is used to collect the current of the DC power supplied to the bridge inverter circuit.
[0034] The cooking device provided in this application includes: a pot body, a power conversion device, a switching device, and multiple heating devices. The power conversion device converts the input power of the cooking device into a working electrical signal. Any type of heating device, after receiving the working electrical signal, heats the food in the pot body. The switching device is connected to the output of the power conversion device and controls one or more heating devices to receive the working electrical signal. The multiple heating devices include at least one electrically operated heating device, which includes two sets of heating electrodes. After receiving the working electrical signal, the heating electrodes electrically heat the food in contact with the pot body. Thus, the cooking device in this application provides multiple heating devices and a switching device to control the power supply of each heating device. For different foods and cooking scenarios, different heating modes can be selected to heat the food, solving the problem of low heating power in the initial stage of electrically operated heating and improving the applicability of the cooking device. Attached Figure Description
[0035] Figure 1 This is a schematic diagram of the structure of a cooking device according to an embodiment of this application;
[0036] Figure 2 This is a schematic diagram of the structure of the heating electrode of a cooking device according to an embodiment of this application;
[0037] Figure 3 This is a schematic diagram of the first direction of the heating electrode of a cooking device according to another embodiment of this application;
[0038] Figure 4 This is a schematic diagram of the second direction of the heating electrode of a cooking device according to another embodiment of this application;
[0039] Figure 5 This is a schematic diagram of the structure of the heating device of a cooking apparatus according to an embodiment of this application;
[0040] Figure 6 This is a schematic diagram of the heating device of a cooking apparatus according to another embodiment of this application;
[0041] Figure 7 This is a schematic diagram of the heating device of a cooking apparatus according to another embodiment of this application;
[0042] Figure 8 This is a schematic diagram of the structure of a cooking device according to another embodiment of this application;
[0043] Figure 9 This is a timing diagram of the turn-on of each switch in a bridge inverter circuit according to another embodiment of this application;
[0044] Figure 10 This is a schematic diagram of the current waveform passed through the induction heating device in one application example of this application;
[0045] Figure 11 This application provides a schematic diagram of the current waveform of an electric heating device and / or a resistance heating device in one application example.
[0046] Explanation of reference numerals in the attached figures
[0047] 100. Power conversion device; 101. First bridge arm; 102. Second bridge arm; 200. Switching device;
[0048] 201. Switch module; 300. Heating device; 301. Electrically powered heating device;
[0049] 3011, First heating electrode; 3012, Second heating electrode; 302, Induction heating device;
[0050] 3021, Heating coil; 303, Resistance heating device; 3031, Resistance heating component;
[0051] 400, Pot body; 500, First current detection device; 600, Second current detection device. Detailed Implementation
[0052] The present application will now be described in further detail with reference to the accompanying drawings and embodiments.
[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
[0054] This application discloses a cooking device, such as... Figure 1As shown, the cooking device includes: a pot body (not shown), a power conversion device 100, a switching device 200, and various heating devices 300. The power conversion device 100 converts the input power of the cooking device into a working electrical signal. The switching device 200 is connected to the output terminal of the power conversion device 100 and controls one or more heating devices 300 to receive working electrical signals. Once any type of heating device 300 receives a working electrical signal, it heats the food in the pot body.
[0055] Among them, the multiple heating devices 300 include at least an electrically powered heating device 301, which includes two sets of heating electrodes. After the heating electrodes are supplied with a working electrical signal, they are used to electrically heat the food in contact with the pot.
[0056] For example, such as Figure 2 As shown, heating electrodes are disposed on the inner wall of the pot body 400. The two sets of heating electrodes include a first heating electrode group and a second heating electrode group. The first heating electrode group includes at least one first heating electrode 3011, and the second heating electrode group includes at least one second heating electrode 3012. The heating electrodes are electrically isolated from each other. The polarities of the first heating electrode 3011 and the second heating electrode 3012 are opposite. The number of first heating electrodes 3011 and the number of second heating electrodes 3012 can be the same or different.
[0057] It should be noted that in related technologies, the input power of cooking equipment is usually DC power or low-frequency AC power (such as mains power). In related technologies, when the heating electrodes are powered on to heat food based on DC or low-frequency AC power, the food to be cooked usually contains moisture, which can easily trigger the electrolysis of water, producing flammable and explosive hydrogen gas, posing a safety hazard.
[0058] In some embodiments, the operating electrical signal is high-frequency alternating current. The power conversion device 100 is used to convert the input power of the cooking device into high-frequency alternating current.
[0059] Here, after the two sets of heating electrodes are supplied with high-frequency current output from the power conversion device 100, the food in the pot body 400 that is in contact with the two sets of heating electrodes is supplied with high-frequency alternating current, and heat is generated based on the resistance of the food itself, thus realizing electric heating.
[0060] It is understood that in some embodiments of this application, the cooking device does not directly use the input power to heat the food in the pot 400. Instead, it uses the power conversion device 100 to convert the input power into high-frequency alternating current before heating. Since the food is less likely to undergo water electrolysis after high-frequency alternating current is applied, the potential safety risks of the heating process are reduced.
[0061] It should be noted that cooking equipment uses electric heating to heat food. Since the heating electrodes need to be in direct contact with the food during heating, if the food is heated by direct current, there is a problem that the heating electrodes will be corroded and oxidized after the cooking equipment has been working for a long time, which will affect the service life of the cooking equipment and contaminate the food. The embodiments of this application heat the food in contact with the heating electrodes by passing high-frequency alternating current through them, which can effectively suppress the problem of corrosion and oxidation of the heating electrodes.
[0062] It should be noted that the embodiments of this application do not specifically limit the form of the heating electrode of the cooking device. In some embodiments, the heating electrode can be, for example, Figure 2 The electrode form shown; in other embodiments, such as Figure 3 and Figure 4 As shown, the heating electrode can also be in the form of a spiral electrode.
[0063] Here, the cooking equipment in this application embodiment includes not only an electrically powered heating device, but also other types and forms of heating devices.
[0064] In some embodiments, the various heating devices 300 further include an induction heating device, including a heating coil. When a working electrical signal is applied to the heating coil, an alternating magnetic field is generated, and the pot body 400 is heated under the action of the alternating magnetic field.
[0065] Here, if the cooking equipment includes an induction heating device, then the pot body 400 is made of metal.
[0066] Here, the induction heating device can be a device that is separate from the pot body 400, for example, it can be installed on the main body of the cooking device.
[0067] Here, as Figure 5 As shown, the cooking device includes heating electrodes and a heating coil 3021. When a working electrical signal is applied to the heating coil 3021, an alternating magnetic field is generated. Under the action of the alternating magnetic field, eddy currents are induced in the pot body. Under the action of the eddy currents, the pot body 400 is heated, thereby heating the food inside.
[0068] Here, as Figure 5 When the cooking equipment shown is in operation, under the control of the switching device 200, the heating electrode or heating coil 3021 is energized to heat the food in the pot 400.
[0069] In some embodiments, the plurality of heating devices 300 further include a resistance heating device, which generates heat after being supplied with an operating electrical signal; the resistance heating device includes at least one of the following: a heating plate, a heating tube, and a heating wire.
[0070] Here, after the resistance heating device is powered on, heat is generated based on the resistance of the resistance heating device itself, and the heat is transferred to the inside of the pot body 400 to heat the food.
[0071] Here, the resistance heating device can be directly installed on the pot body 400, or it can be installed separately from the pot body 400.
[0072] In some embodiments, such as Figure 6 As shown, the resistance heating device includes a resistance heating element 3031, and the cooking device includes a heating electrode and a resistance heating element 3031. The resistance heating element 3031 is a heating plate or a heating tube. The resistance heating device is separately set from the pot body 400. During cooking, the pot body 400 is placed on top of the resistance heating device. After the resistance heating element 3031 is connected to a working electrical signal, it generates heat. The heat is transferred to the inside of the pot body 400 through the bottom of the pot body 400, which is in direct contact with the resistance heating element 3031, to heat the food in the pot body 400.
[0073] Here, as Figure 6 When the cooking device shown is in operation, under the control of the switching device 200, one or more of the heating electrodes and resistance heating components 3031 are energized to heat the food in the pot body 400.
[0074] In some embodiments, the cooking apparatus includes an electrically heated device 301, an induction heating device, and a resistance heating device, such as... Figure 7 As shown, the resistance heating element 3031 is a heating wire, which is disposed on the pot body 400. The cooking device also includes a heating coil 3021. When the cooking device is running, under the control of the switching device 200, one or more of the heating electrode, heating coil 3021 and resistance heating element 3031 are energized to heat the food in the pot body 400.
[0075] It is understood that the cooking equipment in this application embodiment is equipped with multiple heating devices and a switching device for controlling the power supply of each heating device. Based on a heating mode that primarily uses electric heating and multiple heating methods work together, different heating modes can be selected to heat the food for different foods to be cooked and cooking scenarios. This solves the problem of low heating power in the early stages of electric heating and improves the applicability of the cooking equipment.
[0076] It should be noted that the embodiments of this application do not specifically limit the type of heating device 300 of the cooking equipment, and it can be other types of heating devices besides induction heating devices and resistance heating devices; the embodiments of this application also do not specifically limit the number of each type of heating device 300. In some embodiments, the cooking equipment can be provided with multiple heating wires; in some embodiments, the cooking equipment can be provided with heating wires and heating plates.
[0077] For example, such as Figure 8As shown, the switching device 200 includes multiple switch modules 201, each switch module 201 being connected to a heating device in a one-to-one correspondence; the switch module 201 is used to control the power-on state of the corresponding connected heating device.
[0078] Here, each switch module 201 of the switching device 200 can be a component in the form of a relay, contactor, or switching transistor, and is respectively set between the output terminal of the power conversion device 100 and any heating device; when any switch module 201 is turned on, the working electrical signal output by the power conversion device 100 is sent to the corresponding connected heating device; when any switch module 201 is turned off, the working electrical signal output by the power conversion device 100 is not sent to the corresponding connected heating device.
[0079] It is understandable that, such as Figure 8 As shown, the cooking equipment is equipped with an electric heating device 301, an induction heating device 302 and a resistance heating device 303. The switching device 200 includes three switch modules 201, each of which is connected to a heating device.
[0080] For example, the cooking device also includes a control device (not shown in the figure), which is connected to the power conversion device 100 and the switching device 200 respectively, and is used to control the operation of the power conversion device 100 and the switching device 200.
[0081] Here, the control device may be, for example, a microcontroller unit (MCU). The embodiments of this application do not specifically limit the form of the control device.
[0082] Here, the control device is connected to each switch module 201 of the switching device 200, and is specifically used to control the on / off state of each switch module 201 of the switching device 200.
[0083] In one application example, the control device, in response to a user-set cooking mode command and / or heating mode command, determines the heating device currently used to heat the food in the pot and controls the corresponding connected switch module to turn on.
[0084] Here, the control device is specifically used to control the heating power output by the power conversion device 100.
[0085] In some embodiments, the operating electrical signal is a high-frequency alternating current, such as... Figure 8 As shown, the power conversion device includes a bridge inverter circuit (also known as an H-bridge circuit). The bridge inverter circuit is used to convert the incoming DC power into high-frequency AC power. The bridge inverter circuit includes a first bridge arm 101 and a second bridge arm 102. The first bridge arm 101 includes a first upper switch Q1 and a first lower switch Q2; the second bridge arm 102 includes a second upper switch Q3 and a second lower switch Q4.
[0086] Here, the switching device 200 and various heating devices 300 are connected and positioned between the contacts of the first bridge arm 101 and the second bridge arm 102, with the contacts positioned between the switching transistors of the bridge arms; the control device includes a drive circuit, which is connected to the drive terminals of each switching transistor of the bridge inverter circuit.
[0087] For example, the bridge inverter circuit further includes: a first capacitor C1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, and a fifth capacitor C5. The first capacitor C1 is disposed across the two ends of the first upper switch Q1; the second capacitor C2 is disposed across the two ends of the first lower switch Q2; the third capacitor C3 is disposed across the two ends of the second upper switch Q3; the fourth capacitor C4 is disposed across the two ends of the second lower switch Q4; and the fifth capacitor C5 is disposed at the input terminal of the bridge inverter circuit. Here, after DC power is supplied to the first bridge arm 101 and the second bridge arm 102 of the bridge inverter circuit, the DC power is converted into high-frequency AC power and supplied to the switching device 200 and the heating device 300 based on the switching on and off of each switch in the bridge inverter circuit.
[0088] Here, the output terminal of the power conversion device 100 is the contact of the first bridge arm 101 and the second bridge arm 102 of the bridge inverter circuit.
[0089] Here, the capacitors in the bridge inverter circuit serve to stabilize the voltage.
[0090] It should be noted that each switch in the bridge inverter circuit can be a transistor, a MOSFET, or an IGBT; each switch can be a Si switch, a SiC switch, or a group III nitride switch. This embodiment does not specifically limit the material and type of each switch in the bridge inverter circuit.
[0091] It should be noted that if the input power of the cooking equipment is DC, then the input power directly provides DC power to the bridge inverter circuit; if the input power of the cooking equipment is AC, then the power conversion device also includes a rectifier circuit, which is connected to the input terminal of the bridge inverter circuit and is used to rectify the low-frequency AC signal of the input power into DC power before outputting it to the bridge inverter circuit.
[0092] Based on the bridge inverter circuit described above, in one application example, when the cooking equipment is running, the turn-on timing diagram of each switch in the bridge inverter circuit is as follows: Figure 9As shown. The first upper switch Q1 and the first lower switch Q2 of the first bridge arm 101 are turned on separately using a complementary driving method. In order to prevent the first bridge arm 101 from being shot-through due to the simultaneous conduction of the first upper switch Q1 and the first lower switch Q2, a dead time is set when the first upper switch Q1 and the first lower switch Q2 switch on. During the dead time, the first upper switch Q1 and the first lower switch Q2 are both in the off state. The second upper switch Q3 and the second lower switch Q4 of the second bridge arm 102 use the same driving method as the first bridge arm 101. There is a fixed time difference between the turn-on time of the switch of the second bridge arm 102 and the turn-on time of the switch of the first bridge arm 101. This time difference is the conduction angle. The control device can control the heating power of the cooking equipment by adjusting the conduction angle.
[0093] Specifically, depending on the type of heating device used for heating food, the control device of the cooking equipment can control the current waveform supplied to the heating device by adjusting the conduction angle of the bridge inverter circuit. In one application example, the heating device for heating food includes an induction heating device 302, and the current waveform supplied to the induction heating device 302 is as follows: Figure 10 As shown; in one application example, the heating device for heating food includes an electrically energized heating device 301 and / or a resistance heating device 303, and the current waveform supplied to the electrically energized heating device 301 and / or the resistance heating device 303 is as follows: Figure 11 As shown.
[0094] For example, such as Figure 8 As shown, the cooking equipment also includes a first current detection device 500 and a second current detection device 600. The first current detection device 500 is located at the output terminal of the bridge inverter circuit and connected to the control device, used to collect the current of the high-frequency AC power output by the bridge inverter circuit. The second current detection device 600 is located at the input terminal of the bridge inverter circuit and connected to the control device, used to collect the current of the DC power flowing into the bridge inverter circuit.
[0095] In some embodiments, the first current detection device 500 is further used to acquire the voltage of the high-frequency AC power output by the bridge inverter circuit; in some embodiments, the second current detection device 600 is further used to acquire the voltage of the DC power supplied to the bridge inverter circuit.
[0096] It is understood that the cooking equipment in this application embodiment is equipped with a first current detection device 500 and a second current detection device 600, and the current operating status of the cooking equipment is determined based on the acquisition results of the first current detection device 500 and the second current detection device 600.
[0097] In one application example, the control device is configured to: obtain a first current value characterizing the high-frequency AC power output by the bridge inverter circuit based on a first acquisition result collected by the first current detection device 500; and determine the current operating state of the cooking equipment based on the first current value, including: no-load operating state, normal operating state, and overload operating state.
[0098] Understandably, when the control device determines that the cooking equipment is currently in an abnormal operating state such as no-load operation or overload operation based on the first acquisition result collected by the first current detection device 500, it will execute the corresponding protection strategy.
[0099] In one application example, the control device is configured to: obtain a second current value characterizing the DC current flowing into the bridge inverter circuit based on a second acquisition result acquired by the second current detection device 600; and adjust the current of the bridge inverter circuit based on the second current value.
[0100] It should be noted that terms such as "first" and "second" are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.
[0101] Furthermore, the technical solutions described in the embodiments of this application can be combined arbitrarily without conflict.
[0102] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. A cooking apparatus, characterized by, The cooking device comprises: a pot body; a power conversion device for converting an input power of the cooking device into a working electric signal; a plurality of heating devices for heating food in the pot body after being connected to the working electric signal; a switching device connected to an output end of the power conversion device for controlling one or more of the heating devices to be connected to the working electric signal; wherein the plurality of heating devices at least comprises an electric heating device, the electric heating device comprises two groups of heating electrodes, the heating electrodes are used for electric heating of the food in contact with the pot body after being connected to the working electric signal.
2. The cooking apparatus according to claim 1, characterized in that, The heating electrodes are arranged on an inner wall of the pot body.
3. The cooking apparatus according to claim 1, characterized in that, The plurality of heating devices further comprises: an induction heating device comprising a heating coil, the heating coil generates an alternating magnetic field after being connected to the working electric signal, and the pot body is heated under the action of the alternating magnetic field.
4. The cooking apparatus according to claim 1 or 3, characterized in that, The plurality of heating devices further comprises: a resistance heating device, the resistance heating device generates heat after being connected to the working electric signal, and comprises at least one of the following: a heating disc, a heating tube, and a heating wire.
5. The cooking apparatus according to claim 1, wherein The cooking device further comprises: a control device connected to the power conversion device and the switching device respectively for controlling the power conversion device and the switching device to operate.
6. The cooking apparatus according to claim 5, wherein The switching device comprises a plurality of switch modules, each of the switch modules is connected to one of the heating devices in one-to-one correspondence; the switch module is used for controlling the power-on state of the corresponding heating device.
7. The cooking apparatus according to claim 5, wherein The working electric signal is high-frequency alternating current, the power conversion device comprises a bridge inverter circuit for converting input low-frequency direct current into high-frequency alternating current, and the bridge inverter circuit comprises: a first bridge arm comprising a first upper switch tube and a first lower switch tube; a second bridge arm comprising a second upper switch tube and a second lower switch tube; wherein the switching device and the plurality of heating devices are arranged between the junction of the first bridge arm and the junction of the second bridge arm after being connected, and the junction is arranged between the switch tubes of the bridge arm; the control device comprises a driving circuit, and the driving circuit is connected to the driving end of each switch tube of the bridge inverter circuit.
8. The cooking apparatus according to claim 7, characterized in that, The bridge inverter circuit further comprises: a first capacitor arranged at both ends of the first upper switch tube; a second capacitor arranged at both ends of the first lower switch tube; a third capacitor arranged at both ends of the second upper switch tube; a fourth capacitor arranged at both ends of the second lower switch tube; a fifth capacitor arranged at an input end of the bridge inverter circuit.
9. The cooking apparatus according to claim 7, wherein The cooking device further comprises: a first current detection device arranged at an output end of the bridge inverter circuit and connected to the control device for collecting the current of the high-frequency alternating current output by the bridge inverter circuit.
10. The cooking apparatus according to claim 7 or 9, characterized in that, The cooking device further comprises: a second current detection device arranged at an input end of the bridge inverter circuit and connected to the control device for collecting the current of the direct current input into the bridge inverter circuit.