A single-tube low-power continuous heating induction cooker
By introducing power regulation circuits and co-frequency control technology into the induction cooker, the problem that the induction cooker cannot operate continuously at low power is solved, and low power continuous heating is achieved, which reduces heating and noise, and protects the circuit.
Patent Information
- Application Number
- CN202420730183.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-10
- Publication Date
- 2025-04-04
- Estimated Expiration
- 2034-04-10
AI Technical Summary
Existing heating devices such as induction cookers cannot achieve low-power continuous operation, and the excitation switch tube is frequently turned on and stopped at low power, resulting in severe heating and inability to work continuously.
By introducing a power regulation circuit into the induction cooker, the duty cycle of the excitation switch tube and the excitation transformer is controlled by a single chip computer, and the excitation current of the excitation transformer is changed, thereby achieving low-power continuous operation.
The continuous operation of the induction cooker at low power is achieved, the heating problem caused by frequent opening and stop of the excitation switch tube is avoided, the working noise is reduced, and the resonant heating circuit is protected from the impact of large currents at the moment of starting up.
Smart Images
Figure CN222721626U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of electromagnetic heating, in particular to a single-tube low-power continuous heating electromagnetic cooker. Background Art
[0002] Existing heating devices such as induction cookers cannot achieve low-power continuous operation. When the time for the excitation switch tube of the induction cooker to be turned on each time is close to the turn-on delay of the excitation switch tube, the work done by the excitation switch tube will be used for the conduction loss of the excitation switch tube. At this time, the excitation switch tube is in a state of being too hot to work, resulting in an inability to run continuously. Utility Model Content
[0003] The utility model aims to provide a single-tube low-power continuous heating induction cooker, which can realize low-power continuous operation of the induction cooker through a power adjustment circuit to overcome the shortcomings of the prior art.
[0004] A single-tube low-power continuous heating induction cooker, comprising a power input circuit, a power regulation circuit, a heating coil, and a sampling circuit, wherein the power input circuit is connected to the power regulation circuit, and the rear stage of the power regulation circuit is connected to the resonant heating circuit, characterized in that: the AC side of the power input circuit is connected to the voltage detection circuit, the sampling circuit comprises an output sampling circuit and a temperature sampling circuit, the two ends of the resonant heating circuit are connected to the output sampling circuit, the temperature sampling circuit is connected to the single-chip microcomputer control circuit, the power regulation circuit comprises an excitation switch tube Q1, an excitation transformer T1, and a diode D1, the 1st and 2nd feet of the excitation transformer T1 are connected to the power input circuit, and the 3rd foot of the excitation transformer T1 is connected to the power input circuit through the diode D1 and the capacitor C8 is grounded, pin 2 of the excitation transformer T1 is connected to the N pole of the diode D1, pins 4 and 5 of the excitation transformer T1 are connected to the source of the excitation switch tube Q1, the drain of the excitation switch tube Q1 is grounded, and the gate of the excitation switch tube Q1 is connected to the IO port of the single-chip microcomputer through a resistor R14; the power regulation circuit is controlled by the single-chip microcomputer to start when the power output is lower than X%; the resonant heating circuit is composed of a power transistor and its driving circuit, the excitation control is achieved by the excitation switch tube Q1 and the inverter resonance power transistor synchronous frequency control, and the excitation current of the excitation transformer T1 is controlled and the output power is changed by controlling the duty cycle of the excitation switch tube Q1, so as to achieve low-power continuous operation.
[0005] The driving circuit input terminal of the power transistor is connected to the PPG port of the single chip control circuit IC1 via the resistor R17.
[0006] The resonant heating circuit is composed of a power transistor and a driving circuit thereof, and the driving circuit input end of the power transistor is connected to the PPG port of the single-chip control circuit IC1 via a resistor R17.
[0007] It also includes a power conversion circuit, which is provided with a transformer T2. The second tap of the primary side of the transformer T2 is grounded, the first tap of the secondary side of the transformer T2 outputs a first DC low voltage through a diode D8, the middle tap of the secondary side of the transformer T2 is connected to the input end of the switching power chip IC3 through a diode D9, the output end of the switching power chip IC3 outputs a second DC low voltage, and the second tap of the secondary side of the transformer T2 is grounded.
[0008] The control method of the above-mentioned single-tube low-power continuous heating induction cooker is as follows: when the electromagnetic heating device requires a power output lower than X%, the excitation switch tube Q1 is controlled by the single-chip microcomputer control circuit to change the inductance of the excitation transformer, thereby reducing the output current of the excitation transformer, thereby reducing the power of the resonant heating circuit, so that the resonant heating circuit can operate continuously at low power.
[0009] The value range of X is 50-60.
[0010] The beneficial effects of the utility model are:
[0011] 1. The utility model controls the output current by means of a power regulation circuit. When heating with low power (less than 50% of the nominal power), the control method of directly regulating the duty cycle through the power transistor is changed. Instead, the inductance of the excitation transformer is changed by the single chip microcomputer to reduce the output current. The utility model can avoid the serious heating problem of the power transistor at a low duty cycle and prevent the explosion phenomenon.
[0012] 2. The utility model overcomes the inherent defect of frequent opening and stopping of the excitation switch tube during low-power heating, thereby eliminating the working noise caused by its frequent starting.
[0013] 3. When the existing induction cooker is just turned on, it will produce a large current impact on the resonant heating circuit. The utility model sets an excitation transformer in the power regulation circuit. When the excitation transformer is not working, it is equivalent to a large inductor, which absorbs the large current impact at the moment of starting up and protects the subsequent resonant heating circuit. When the power regulation circuit is started, the current can be reduced to adjust the power. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 This is the power input circuit diagram of the induction cooker of the utility model.
[0015] Figure 2 The utility model is an induction cooker power regulation circuit diagram.
[0016] Figure 3 This is a resonant heating circuit diagram of an induction cooker of the utility model.
[0017] Figure 4 This is the voltage detection circuit diagram of the induction cooker of the utility model.
[0018] Figure 5 This is the single chip microcomputer control circuit diagram of the induction cooker of the utility model.
[0019] Figure 6 This is the output sampling circuit diagram of the induction cooker of the utility model.
[0020] Figure 7 This is a power conversion circuit diagram of an induction cooker of the utility model.
[0021] Figure 8 This is a temperature sampling circuit diagram of an induction cooker of the utility model. DETAILED DESCRIPTION
[0022] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.
[0023] In the description of the present invention, it should be understood that the terms "center", "lateral", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. Unless otherwise specified, "plurality" means two or more.
[0024] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection. It can also be a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.
[0025] See also Figure 1-8 The utility model discloses a single-tube low-power continuous heating induction cooker, including a power input circuit, a power regulation circuit, a heating coil, a sampling circuit, and a power conversion circuit. The power input circuit is connected to the power regulation circuit, and the rear stage of the power regulation circuit is connected to the resonant heating circuit.
[0026] The AC side of the power input circuit is connected to the voltage detection circuit, the sampling circuit includes an output sampling circuit and a temperature sampling circuit, the two ends of the resonant heating circuit are connected to the output sampling circuit, the temperature sampling circuit is connected to the single-chip control circuit, the power regulation circuit includes an excitation switch tube Q1, an excitation transformer T1, and a diode D1, the 1st and 2nd pins of the excitation transformer T1 are connected to the power input circuit, the 3rd pin of the excitation transformer T1 is grounded through the diode D1 and the capacitor C8, the 2nd pin of the excitation transformer T1 is connected to the N pole of the diode D1, the 4th and 5th pins of the excitation transformer T1 are connected to the source of the excitation switch tube Q1, the drain of the excitation switch tube Q1 is grounded, and the gate of the excitation switch tube Q1 is connected to the IO port of the single-chip computer through the resistor R14; the power regulation circuit is controlled by the single-chip computer to start at low power (for example, the power output is required to be less than 60%), the resonant heating circuit is composed of a power transistor and its drive circuit, and the excitation is controlled by the excitation switch tube Q1 and the power transistor (see Figure 3 The IGBT device marked as Q5) is controlled at the same frequency, and the excitation current is controlled and the output power is changed by controlling the duty cycle of the excitation switch tube Q1 to achieve low-power continuous operation.
[0027] The excitation switch tube Q1 adopts a MOS tube, and as an alternative, an IGBT or other triode form can also be selected.
[0028] The input end of the driving circuit of the power transistor is connected to the PPG port of the single-chip control circuit IC1 through the resistor R17. The power conversion circuit is provided with a transformer T2, the second tap of the primary side of the transformer T2 is grounded, the first tap of the secondary side of the transformer T2 outputs a first DC low voltage through a diode D8, the middle tap of the secondary side of the transformer T2 is connected to the input end of the switching power chip IC3 through a diode D9, the output end of the switching power chip IC3 outputs a second DC low voltage, and the second tap of the secondary side of the transformer T2 is grounded.
[0029] The heating control method of the single-tube low-power continuous heating induction cooker is as follows: when the electromagnetic heating device needs to output power lower than the set power, the excitation switch tube Q1 is controlled by the single-chip control circuit to change the inductance of the excitation transformer, reduce the output current of the excitation transformer, thereby reducing the power of the resonant heating circuit, so that the resonant heating circuit can operate continuously at low power. The set low power is 50-60% of the rated power value.
[0030] All components involved in the present invention may be general standard parts or components known to those skilled in the art, and their structures, principles and control methods are known to those skilled in the art through technical manuals or conventional experimental methods.
[0031] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, other single-tube low-power continuous heating induction cookers that adopt the same or similar technical features as the above-mentioned embodiments of the present invention are within the protection scope of the present invention.
Claims
1. A single-tube low-power continuous heating induction cooker, comprising a power input circuit, a power regulation circuit, a heating coil, and a sampling circuit, wherein the power input circuit is connected to the power regulation circuit, and the rear stage of the power regulation circuit is connected to the resonant heating circuit, characterized in that: The AC side of the power input circuit is connected to the voltage detection circuit, the sampling circuit includes an output sampling circuit and a temperature sampling circuit, the two ends of the resonant heating circuit are connected to the output sampling circuit, the temperature sampling circuit is connected to the single-chip control circuit, the power regulation circuit includes an excitation switch tube Q1, an excitation transformer T1, and a diode D1, the 1st and 2nd pins of the excitation transformer T1 are connected to the power input circuit, the 3rd pin of the excitation transformer T1 is grounded through the diode D1 and the capacitor C8, the 2nd pin of the excitation transformer T1 is connected to the N pole of the diode D1, and the 4th and 5th pins of the excitation transformer T1 are connected to the excitation The source of the switch tube Q1 and the drain of the excitation switch tube Q1 are grounded, and the gate of the excitation switch tube Q1 is connected to the IO port of the single-chip microcomputer through the resistor R14; the power regulation circuit is controlled by the single-chip microcomputer to start when the power output is lower than X%; the resonant heating circuit is composed of a power transistor and its drive circuit, and the excitation control is achieved by controlling the excitation switch tube Q1 and the inverter resonance power transistor at the same frequency, and controlling the duty cycle of the excitation switch tube Q1 to control the excitation current of the excitation transformer T1, change the output power, and achieve low-power continuous operation, and the value range of X is 50-60.
2. The single-tube low-power continuous heating induction cooker according to claim 1, characterized in that: The input end of the driving circuit of the power transistor is connected to the PPG port of the single chip control circuit IC1 via the resistor R17.
3. The single-tube low-power continuous heating induction cooker according to claim 1, characterized in that: It also includes a power conversion circuit, which is provided with a transformer T2. The second tap of the primary side of the transformer T2 is grounded, the first tap of the secondary side of the transformer T2 outputs a first DC low voltage through a diode D8, the middle tap of the secondary side of the transformer T2 is connected to the input end of the switching power chip IC3 through a diode D9, the output end of the switching power chip IC3 outputs a second DC low voltage, and the second tap of the secondary side of the transformer T2 is grounded.