Electromagnetic heating control circuit, electromagnetic heating equipment and control method thereof

Abstract

The invention discloses an electromagnetic heating control circuit, electromagnetic heating equipment and a control method thereof, and the electromagnetic heating control circuit comprises a power switch tube; the driving unit is configured to drive the power switch tube to be switched on or switched off; and the soft driving control unit is configured to perform reduction control on the power supply voltage provided for the driving unit when the driving unit drives the power switch tube to be turned on, so that the power switch tube is turned on softly. According to the circuit, the driving unit is controlled to drive the driving voltage of the power switch tube, so that the power switch tube is softly turned on, the collector voltage of the power switch tube is released to zero volt, the turn-on voltage and the turn-on current are reduced, the instantaneous loss of the power switch tube is reduced, the temperature rise of the power switch tube is reduced, and the service life of the power switch tube is prolonged.

Description

Technical Field

[0001] The present application relates to the field of electromagnetic heating technology, and in particular to an electromagnetic heating control circuit, an electromagnetic heating device and a control method thereof. Background Art

[0002] The application scenarios of IH (Induction Heating) products (such as induction cookers and electromagnetic range cookers) in related technologies are constantly expanding. The use of functions such as making soup, stir-frying, and frying steak is increasing. In order to achieve better results in different functional applications, the types of cookware used by consumers are also increasing. Some cookware on the market have poor resonant heating parameters. The collector voltage of the IGBT (Insulate-Gate Bipolar Transistor) in the circuit cannot resonate to zero voltage, and the IGBT cannot be turned on at zero voltage. Therefore, the IGBT has problems such as high turn-on voltage, large turn-on current, large reverse current, and high collector voltage. This leads to a high temperature rise of the IGBT, which reduces the service life of the IGBT. Summary of the Invention

[0003] The present invention aims to at least partially address one of the technical problems in the related art. To this end, a first object of the present invention is to provide an electromagnetic heating control circuit that controls the driving voltage of a power switch tube driven by a driving unit to achieve soft-turn-on of the power switch tube, releasing the collector voltage of the power switch tube to zero volts. This reduces the turn-on voltage and turn-on current, lowers the instantaneous loss of the power switch tube, reduces the temperature rise of the power switch tube, and thereby increases the life of the power switch tube.

[0004] The second object of the present invention is to provide an electromagnetic heating device.

[0005] The third object of the present invention is to provide a control method for electromagnetic heating equipment.

[0006] A fourth object of the present invention is to provide a computer-readable storage medium.

[0007] A fifth object of the present invention is to provide an electromagnetic heating device.

[0008] To achieve the above-mentioned purpose, an electromagnetic heating control circuit is proposed according to an embodiment of the first aspect of the present invention, comprising: a power switch tube; a drive unit configured to drive the power switch tube to turn on or off; and a soft drive control unit configured to control the reduction of the power supply voltage provided to the drive unit when the drive unit drives the power switch tube to turn on, so as to enable the power switch tube to be softly turned on.

[0009] According to an embodiment of the present invention, an electromagnetic heating control circuit includes a power switch tube, a drive unit and a soft drive control unit, wherein the drive unit is configured to drive the power switch tube to turn on or off, and the soft drive control unit is configured to control the reduction of the power supply voltage provided to the drive unit when the drive unit drives the power switch tube to turn on, so that the drive voltage of the drive unit is reduced to the drive voltage of the amplification region of the power switch tube, so that the power switch tube is in a linear turn-on state, and the collector voltage is released to zero volts, thereby reducing the turn-on voltage and turn-on current, reducing the instantaneous loss of the power switch tube, reducing the temperature rise of the power switch tube, and thus improving the life of the power switch tube.

[0010] According to an embodiment of the present invention, the soft driving control unit is enabled when the driving unit drives the power switch tube to turn on, so as to reduce the driving voltage applied to the power switch tube by the driving unit by dividing the power supply voltage.

[0011] According to an embodiment of the present invention, the soft driving control unit is disabled after being enabled for a first preset time, so that the driving unit drives the power switch tube to enter a saturated on state based on the power supply voltage.

[0012] According to an embodiment of the present invention, the first preset time is shorter than the turn-on time of the power switch tube.

[0013] According to one embodiment of the present invention, the soft driving control unit is enabled in each switching cycle of the power switch tube.

[0014] According to one embodiment of the present invention, the soft driving control unit is enabled during a set switching period of the power switch tube, wherein the set switching period is determined based on electromagnetic heating parameters.

[0015] According to one embodiment of the present invention, the soft drive control unit includes: a first resistor, one end of the first resistor is suitable for connecting to the drive unit; a first transistor, the emitter of the first transistor is connected to the other end of the first resistor, and the collector of the first transistor is grounded; a second resistor, one end of the second resistor is connected to the base of the first transistor; a third resistor, one end of the third resistor is suitable for accessing the power supply voltage, the other end of the third resistor is connected to the other end of the second resistor, and has a first node, the first node is suitable for receiving an enable control signal, wherein the enable control signal is used to enable the soft drive control unit.

[0016] According to one embodiment of the present invention, the driving unit includes: a second triode, the emitter of the second triode is grounded, and the base of the second triode is suitable for receiving a driving control signal of the power switch tube; a fourth resistor, one end of the fourth resistor is suitable for connecting to the power supply voltage, the other end of the fourth resistor is connected to the collector of the second triode, and has a second node, and the second node is connected to one end of the first resistor; a third triode, the base of the third triode is connected to the second node, and the collector of the third triode is connected to the power supply voltage through a fifth resistor; a fourth triode, the base of the fourth triode is connected to the base of the third triode, and the collector of the fourth triode is connected to the reference ground; a sixth resistor, one end of the sixth resistor is connected to the emitter of the third triode, and has a third node, and the other end of the sixth resistor is connected to the emitter of the fourth triode, wherein the third node is suitable for connecting to the control electrode of the power switch tube.

[0017] According to one embodiment of the present invention, the driving unit further includes: a seventh resistor, one end of which is connected to the base of the second transistor; an eighth resistor, one end of which is suitable for receiving a power supply voltage, and the other end of the eighth resistor is connected to the other end of the seventh resistor to serve as a control signal receiving end of the driving unit.

[0018] According to one embodiment of the present invention, the electromagnetic heating control circuit further includes: a control unit configured to obtain the actual power of the electromagnetic heating device and output an enable control signal to the soft drive control unit when the actual power is less than a preset power threshold.

[0019] According to an embodiment of the present invention, the control unit is further configured to output a driving control signal to the driving unit, so as to drive the power switch tube to be turned on or off through the driving unit.

[0020] To achieve the above-mentioned object, an electromagnetic heating device is provided according to a second embodiment of the present invention, comprising the electromagnetic heating control circuit of any of the aforementioned embodiments.

[0021] According to the electromagnetic heating device of an embodiment of the present invention, by adopting the above-mentioned electromagnetic heating control circuit, the driving voltage of the power switch tube is controlled by the driving unit to make the power switch tube soft-turn on, and the collector voltage of the power switch tube is released to zero volts, thereby reducing the turn-on voltage and turn-on current, reducing the instantaneous loss of the power switch tube, reducing the temperature rise of the power switch tube, and thus improving the life of the power switch tube.

[0022] To achieve the above-mentioned purpose, according to an embodiment of the third aspect of the present invention, a control method for an electromagnetic heating device is proposed, the electromagnetic heating device includes an electromagnetic heating control circuit of any of the aforementioned embodiments, and the method includes: in response to an enable control instruction, controlling the soft drive control unit to turn on, so that the soft drive control unit controls the reduction of the power supply voltage provided to the drive unit when the drive unit drives the power switch tube to turn on, so that the power switch tube is soft-turned on.

[0023] According to the control method of the electromagnetic heating equipment of the embodiment of the present invention, in response to the enable control instruction, the soft drive control unit is controlled to turn on. When the drive unit drives the power switch tube to turn on, the soft drive control unit controls the reduction of the power supply voltage provided to the drive unit, so that the drive voltage of the drive unit is reduced to the drive voltage of the amplification region of the power switch tube, so that the power switch tube is in a linear turn-on state, and the collector voltage is released to zero volts, thereby reducing the turn-on voltage and turn-on current, reducing the instantaneous loss of the power switch tube, reducing the temperature rise of the power switch tube, and thus improving the life of the power switch tube.

[0024] According to one embodiment of the present invention, the soft drive control unit controls the reduction of the power supply voltage provided to the drive unit when the drive unit drives the power switch tube to turn on, including: the soft drive control unit divides the power supply voltage to reduce the drive voltage applied to the power switch tube by the drive unit.

[0025] According to an embodiment of the present invention, the soft driving control unit is disabled after the on time reaches a first preset time, so that the driving unit drives the power switch tube to enter a saturated on state based on the power supply voltage.

[0026] According to an embodiment of the present invention, the first preset time is shorter than the turn-on time of the power switch tube.

[0027] According to an embodiment of the present invention, controlling the soft driving control unit to turn on includes: controlling the soft driving control unit to turn on in each switching cycle of the power switch tube.

[0028] According to one embodiment of the present invention, controlling the soft drive control unit to turn on includes: controlling the soft drive control unit to turn on during a set switching cycle of the power switch tube, wherein the set switching cycle is determined based on electromagnetic heating parameters.

[0029] According to an embodiment of the present invention, before controlling the soft drive control unit to start, the method further includes: obtaining the actual power of the electromagnetic heating device; and generating an enable control instruction when the actual power is less than a preset power threshold.

[0030] To achieve the above-mentioned purpose, according to a fourth aspect of the present invention, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the control method of the electromagnetic heating device of any of the aforementioned embodiments is implemented.

[0031] According to the computer-readable storage medium of an embodiment of the present invention, by executing a computer program of the control method of the above-mentioned electromagnetic heating equipment, the driving voltage of the power switch tube is controlled by the driving unit to make the power switch tube soft-turn on, and the collector voltage of the power switch tube is released to zero volts, thereby reducing the turn-on voltage and turn-on current, reducing the instantaneous loss of the power switch tube, reducing the temperature rise of the power switch tube, and thus improving the life of the power switch tube.

[0032] To achieve the above-mentioned purpose, according to an embodiment of the fifth aspect of the present invention, an electromagnetic heating device is proposed, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the control method of the electromagnetic heating device of any of the aforementioned embodiments is implemented.

[0033] According to the motor controller of an embodiment of the present invention, a computer program of the control method of the above-mentioned electromagnetic heating equipment is executed by a processor, and the driving voltage of the power switch tube is controlled by the drive unit to make the power switch tube soft-turn on, and the collector voltage of the power switch tube is released to zero volts, thereby reducing the turn-on voltage and turn-on current, reducing the instantaneous loss of the power switch tube, reducing the temperature rise of the power switch tube, and thus improving the life of the power switch tube.

[0034] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a structural diagram of an electromagnetic heating control circuit according to an embodiment of the present invention;

[0036] Figure 2 is a structural diagram of an electromagnetic heating control circuit according to another embodiment of the present invention;

[0037] Figure 3 is a waveform diagram of enabling the soft drive control unit in each switching cycle according to one embodiment of the present invention;

[0038] Figure 4 is a circuit diagram of an electromagnetic heating control circuit according to one embodiment of the present invention;

[0039] Figure 5 is a circuit diagram of an electromagnetic heating control circuit according to another embodiment of the present invention;

[0040] Figure 6 1 is a waveform diagram of enabling a soft drive control unit according to actual power according to one embodiment of the present invention;

[0041] Figure 7 is a system schematic diagram of an electromagnetic heating device according to one embodiment of the present invention;

[0042] Figure 8 is a circuit diagram of an electromagnetic heating device according to one embodiment of the present invention;

[0043] Figure 9 is a flow chart of a control method for an electromagnetic heating device according to an embodiment of the present invention;

[0044] Figure 10 is a flow chart of a control method for an electromagnetic heating device according to a specific embodiment of the present invention;

[0045] Figure 11 4 is a system schematic diagram of an electromagnetic heating device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0046] The following describes embodiments of the present invention in detail, examples of which 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 intended to be used to explain the present invention, and are not to be construed as limiting the present invention.

[0047] The electromagnetic heating control circuit, electromagnetic heating device, control method thereof, and storage medium according to embodiments of the present invention will be described below with reference to the accompanying drawings.

[0048] Figure 1 FIG. 1 is a schematic diagram of the structure of an electromagnetic heating control circuit according to an embodiment of the present invention. Figure 1 As shown, the electromagnetic heating control circuit includes: a power switch tube IGBT, a drive unit 10 and a soft drive control unit 20.

[0049] Among them, the driving unit 10 is configured to drive the power switch tube IGBT to turn on or off; the soft drive control unit 20 is configured to control the reduction of the power supply voltage VDD provided to the driving unit 10 when the driving unit 10 drives the power switch tube IGBT to turn on, so as to make the power switch tube IGBT soft-turn on.

[0050] Specifically, the collector of the power switching tube IGBT is adapted to input a resonant voltage, and the emitter of the power switching tube IGBT is grounded. When the resonant voltage resonates to 0, the power switching tube IGBT is turned on. At this time, the collector voltage of the power switching tube IGBT is 0, and the turn-on voltage, turn-on current, and turn-on loss of the power switching tube IGBT are relatively low. However, when the resonant parameters of the cookware used by the user are poor, the resonant voltage cannot resonate to 0, causing the collector voltage of the power switching tube IGBT to be greater than 0. If the power switching tube IGBT is turned on at this time, the turn-on voltage, turn-on current, and loss of the power switching tube IGBT are relatively high, resulting in a relatively high temperature rise of the power switching tube IGBT. The drive unit 10 outputs a drive voltage Vge to the power switching tube IGBT to drive the power switching tube IGBT on or off. When the drive unit 10 drives the power switch tube IGBT to turn on, the soft drive control unit 20 reduces the power supply voltage VDD of the drive unit 10, so that the drive voltage Vge output by the drive unit 10 is reduced to the drive voltage of the amplification region of the power switch tube IGBT, so that the power switch tube IGBT is in a linear turn-on state, and the collector voltage of the power switch tube IGBT is slowly reduced to zero volts through the current, so as to distribute the instantaneous conduction loss to the time when the amplification region drive voltage is turned on, thereby reducing the switching loss.

[0051] In an optional embodiment, as Figure 2 As shown, the electromagnetic heating control circuit further includes a power supply unit 30 , which is connected to the driving unit 10 to provide a power supply voltage VDD to the driving power supply.

[0052] In the above embodiment, the soft drive control unit controls the drive unit to reduce the drive voltage to softly turn on the power switch tube, releases the collector voltage of the power switch tube to zero volts, reduces the turn-on voltage and turn-on current, reduces the instantaneous loss of the power switch tube, reduces the temperature rise of the power switch tube, and thus improves the life of the power switch tube.

[0053] In some embodiments, the soft drive control unit 20 is enabled when the drive unit 10 drives the power switch tube IGBT to turn on, so as to reduce the drive voltage Vge applied by the drive unit 10 to the power switch tube IGBT by dividing the power supply voltage VDD.

[0054] Specifically, the soft drive control unit 20 divides the power supply voltage VDD when the power switch tube IGBT is turned on, so that the driving voltage Vge applied by the drive unit 10 to the power switch tube IGBT is the divided power supply voltage VDD, thereby reducing the driving voltage Vge of the power switch tube IGBT, so that the power switch tube IGBT is in the amplification area.

[0055] In an optional embodiment, as Figure 2As shown, the electromagnetic heating control circuit also includes a synchronous detection unit 40, which is suitable for detecting the collector voltage of the power switch tube IGBT. When the synchronous detection unit 40 detects that the collector voltage is less than a preset voltage value, the drive unit 10 drives the power switch tube IGBT to turn on. At the same time, the soft drive control unit 20 is enabled to divide the power supply voltage VDD so that the drive voltage Vge of the drive unit 10 is the divided power supply voltage VDD. The drive unit 10 drives the power switch tube IGBT to turn on according to the divided power supply voltage VDD, so that the power switch tube IGBT is soft-turned on.

[0056] In some embodiments, the soft driving control unit 20 is disabled after being enabled for a first preset time, so that the driving unit 10 drives the power switch tube IGBT into a saturated on state based on the power supply voltage VDD.

[0057] Specifically, after the soft drive control unit 20 is enabled for a first preset time, the soft drive control unit 20 stops dividing the power supply voltage VDD, and the drive unit 10 drives the power switch tube IGBT according to the power supply voltage VDD, so that the power switch tube IGBT enters a saturation state.

[0058] In the above embodiment, by controlling the working state of the soft drive control unit and adjusting the magnitude of the drive voltage, the power switch tube first enters the linear turn-on state and then enters the saturation state. Compared with directly controlling the power switch tube to enter the saturation state, the turn-on loss of the power switch tube can be effectively reduced, thereby reducing the temperature rise of the power switch tube.

[0059] Furthermore, in some embodiments, the first preset time is less than a turn-on time of the power switch tube IGBT.

[0060] That is to say, the time that the power switch tube IGBT is in the soft turn-on state is shorter than the turn-on time of the power switch tube IGBT. If the power switch tube IGBT is in the soft turn-on state for a long time, the turn-on current of the power switch tube IGBT gradually increases, and the loss of the power switch tube IGBT will also gradually increase, resulting in a higher temperature rise of the power switch tube IGBT.

[0061] In some embodiments, the soft drive control unit 20 is enabled in each switching cycle of the power switch tube IGBT.

[0062] It is understandable that the soft drive control unit 20 can be enabled in each switching cycle, that is, the power switch tube IGBT is turned on in a soft turn-on manner in each switching cycle and then enters a saturation state, which can reduce the temperature rise of the power switch tube IGBT.

[0063] In some embodiments, the soft driving control unit 20 is enabled during a set switching cycle of the power switch tube IGBT, wherein the set switching cycle is determined based on the electromagnetic heating parameter.

[0064] That is to say, the soft drive control unit 20 is not limited to being enabled in each switching cycle, and the set switching cycle that the soft drive control unit 20 needs to be enabled can also be determined based on the electromagnetic heating parameters. The electromagnetic heating parameters can be electromagnetic heating power or electromagnetic heating requirements. For example, Figure 3 As shown, the soft drive control unit 20 can be enabled within a preset time interval and in each switching cycle of the power switch tube IGBT. For example, for a heating mains envelope of 10ms, the electromagnetic heating requirement is 3-6ms, and the soft drive control unit 20 needs to be enabled. The set switching cycle of each switching cycle between 3-6ms, and the power switch tube IGBT is turned on in a hard-on manner at other times (that is, the power switch tube IGBT directly enters the saturation state). Between 3-6ms, the soft drive control unit 20 is enabled in each switching cycle, and the driving voltage Vge of the power switch tube IGBT is the divided power supply voltage VDD. After the first preset time, the soft drive control unit 20 is disabled, and the driving voltage Vge of the power switch tube IGBT is the power supply voltage VDD. Compared with always using the hard-on method, the temperature rise of the power switch tube IGBT is reduced, thereby increasing the service life of the power switch tube IGBT, and further improving the performance of the electromagnetic heating device.

[0065] In some embodiments, as Figure 4 As shown, the soft drive control unit 20 includes: a first resistor R1, a first transistor Q1, a second resistor R2 and a third resistor R3, wherein one end of the first resistor R1 is suitable for connecting to the drive unit 10; the emitter of the first transistor Q1 is connected to the other end of the first resistor R1, and the collector of the first transistor Q1 is grounded; one end of the second resistor R2 is connected to the base of the first transistor Q1; one end of the third resistor R3 is suitable for connecting to the power supply voltage VDD, the other end of the third resistor R3 is connected to the other end of the second resistor R2, and has a first node J1, the first node J1 is suitable for receiving an enable control signal spwmout, wherein the enable control signal spwmout is used to enable the soft drive control unit 20.

[0066] Specifically, when the enable control signal spwmout is at a low level, the base of the first transistor Q1 is at a low level, and the first transistor Q1 is in a turned-off state. Therefore, the first resistor R1 cannot divide the power supply voltage VDD, and the soft drive control unit 20 is in a disabled state. When the enable control signal spwmout is at a high level, the base of the first transistor Q1 is at a high level, and the first transistor Q1 is in an turned-on state. The first resistor R1 divides the power supply voltage VDD, and the soft drive control unit 20 is enabled.

[0067] In some embodiments, as Figure 4 As shown, the driving unit 10 includes: a second transistor Q2, a fourth resistor R4, a third transistor Q3, a fourth transistor Q4 and a sixth resistor R6, wherein the emitter of the second transistor Q2 is grounded, and the base of the second transistor Q2 is suitable for receiving the driving control signal ppgout of the power switch tube IGBT; one end of the fourth resistor R4 is suitable for connecting to the power supply voltage VDD, and the other end of the fourth resistor R4 is connected to the collector of the second transistor Q2 and has a second node J2, and the second node J2 is connected to one end of the first resistor R1. The base of the third transistor Q3 is connected to the second node J2, and the collector of the third transistor Q3 is connected to the power supply voltage VDD through the fifth resistor; the base of the fourth transistor Q4 is connected to the base of the third transistor Q3, and the collector of the fourth transistor Q4 is connected to the reference ground; one end of the sixth resistor R6 is connected to the emitter of the third transistor Q3 and has a third node J3, and the other end of the sixth resistor R6 is connected to the emitter of the fourth transistor Q4, wherein the third node J3 is suitable for being connected to the control electrode of the power switch tube IGBT.

[0068] Specifically, the third transistor Q3 and the fourth transistor Q4 form a push-pull circuit. When the drive control signal ppgout is high, the second transistor Q2 turns on, pulling the bases of the third and fourth transistors Q3 and Q4 to a low level. Consequently, the third and fourth transistors Q3 and Q4 are turned off, and the power switch IGBT is turned off. When the drive control signal ppgout is low, the second transistor Q2 turns off, and the base voltages of the third and fourth transistors Q3 and Q4 are controlled by the soft drive control unit 20. When the driving control signal ppgout is at a low level and the enabling control signal spwmout is at a high level, the base of the first transistor Q1 is at a high level, the first transistor Q1 is in an on state, the power supply voltage VDD flows into the ground through the voltage divider of the fourth resistor R4 and the first resistor R1, the base voltages of the third transistor Q3 and the fourth transistor Q4 are greater than 0 and less than the power supply voltage VDD, so the third transistor Q3 is in an on state, and the conduction condition of the fourth transistor Q4 is V_e>V_b+B, where B is approximately 0.7V. At this time, the voltage does not meet the conduction condition of the fourth transistor Q4, and the third transistor Q3 is in an on state. The fourth transistor Q4 is in the off state. When the transistor is turned on, the emitter voltage is about 0.7V lower than the base voltage. Therefore, the emitter voltage of the third transistor Q3 is the base voltage of the third transistor Q3 -0.7V. Therefore, the emitter voltage of the third transistor Q3 is VDD*R1 / (R4+R1)-0.7V. The driving voltage Vge is approximately equal to the emitter voltage of the third transistor Q3. The driving voltage Vge is VDD*R1 / (R4+R1)-0.7V. Therefore, the driving voltage Vge is greater than 0 and less than the power supply voltage VDD. The power switch tube IGBT is in a linear turn-on state. When the drive control signal ppgout is at a low level and the enable control signal spwmout is at a low level, the base of the first transistor Q1 is at a low level, the first transistor Q1 is in an off state, and the fourth resistor R4 pulls the base voltages of the third transistor Q3 and the fourth transistor Q4 to the power supply voltage VDD, so the drive voltage Vge is approximately equal to the power supply voltage VDD, and the power switch tube IGBT is in a saturated state.

[0069] Furthermore, in some embodiments, Figure 4 As shown, the driving unit 10 also includes: a seventh resistor R7 and an eighth resistor R8, wherein one end of the seventh resistor R7 is connected to the base of the second transistor Q2; one end of the eighth resistor R8 is suitable for connecting to the power supply voltage VDD, and the other end of the eighth resistor R8 is connected to the other end of the seventh resistor R7 to serve as a control signal receiving end of the driving unit 10.

[0070] It can be understood that the other end of the seventh resistor R7 is suitable for inputting the drive control signal ppgout. The seventh resistor R7 can limit the current of the drive control signal ppgout to prevent the drive control signal ppgout from damaging the second transistor Q2, thereby further improving the life of the electromagnetic heating equipment.

[0071] In some embodiments, as Figure 5 As shown, the electromagnetic heating control circuit further includes: a control unit 50 configured to obtain the actual power of the electromagnetic heating device and output an enable control signal spwmout to the soft drive control unit 20 when the actual power is less than a preset power threshold.

[0072] Specifically, if Figure 6 As shown, when the actual power is less than the preset power threshold, the control unit 50 outputs the enable control signal spwmout to the soft driver control unit 20 in each switching cycle, enabling the soft driver control unit 20 to divide the power supply voltage VDD. After a first preset time, the control unit 50 stops outputting the enable control signal spwmout, at which point the soft driver control unit 20 stops dividing the power supply voltage VDD. When the actual power is greater than or equal to the preset power threshold, the control unit 50 does not output the enable control signal spwmout to the soft driver control unit 20.

[0073] In an optional embodiment, the control unit 50 is further configured to control the electromagnetic heating device to perform heating according to a preset target power before obtaining the actual power of the electromagnetic heating device. The control unit 50 controls the electromagnetic heating device to perform heating according to the preset target power and then obtains the actual power.

[0074] In the above embodiment, the soft drive control unit is enabled according to the actual power of the electromagnetic heating device, which can effectively reduce the turn-on current of the power switch tube, realize low-power heating technology, and reduce heating noise, thereby improving the reliability of the electromagnetic heating device.

[0075] Furthermore, in some embodiments, the control unit 50 is further configured to output a driving control signal ppgout to the driving unit 10 , so as to drive the power switch tube IGBT to be turned on or off through the driving unit 10 .

[0076] It is understandable that the control unit 50 also outputs a driving control signal ppgout to the base of the second transistor Q2 to control the switching of the push-pull circuit composed of the third transistor Q3 and the fourth transistor Q4, thereby driving the switching of the power switch tube IGBT.

[0077] In an optional embodiment, the control unit 50 is connected to the synchronous detection unit 40. The control unit 50 is further configured to output an enable control signal spwmout to the soft drive control unit 20 and output a drive control signal ppgout to the drive unit 10 when the collector voltage of the power switch tube IGBT is less than a preset voltage value. When the synchronous detection unit 40 detects that the collector voltage is less than the preset voltage value, the control unit 50 controls the soft drive control unit 20 to be enabled and controls the drive unit 10 to drive the power switch tube IGBT to turn on.

[0078] In summary, the electromagnetic heating control circuit according to an embodiment of the present invention includes a power switch tube, a drive unit and a soft drive control unit, wherein the drive unit is configured to drive the power switch tube to turn on or off, and the soft drive control unit is configured to control the reduction of the power supply voltage provided to the drive unit when the drive unit drives the power switch tube to turn on, so that the drive voltage of the drive unit is reduced to the drive voltage of the amplification region of the power switch tube, so that the power switch tube is in a linear turn-on state, and the collector voltage is released to zero volts, thereby reducing the turn-on voltage and turn-on current, reducing the instantaneous loss of the power switch tube, and reducing the temperature rise of the power switch tube, thereby improving the life of the power switch tube.

[0079] Corresponding to the above embodiment, the embodiment of the present invention further provides an electromagnetic heating device. Figure 7 As shown, the electromagnetic heating device 200 includes the electromagnetic heating control circuit 100 of any of the aforementioned embodiments.

[0080] In an optional embodiment, as Figure 8 As shown, the electromagnetic heating device 200 further includes a rectifier unit 201, a zero-crossing detection unit 202, and a resonant heating unit 203. The rectifier unit 201 is adapted to rectify the input AC mains power to generate DC power, the zero-crossing detection unit 202 is connected to the input end of the rectifier unit 201, and detects the zero-crossing signal of the AC mains power, and the input end of the resonant heating unit 203 is connected to the output end of the rectifier unit 201 to perform resonant heating based on the DC power.

[0081] Furthermore, the resonant heating unit 203 includes a first capacitor C1 and a coil L and a resonant capacitor C in parallel. The first capacitor C1 is connected in parallel between the two ends of the rectifier unit 201, one end of the resonant capacitor C is connected to the output end of the rectifier unit 201, and the other end of the resonant heating unit 203 is connected to the collector of the power switching tube IGBT. The coil L is connected in parallel between the two ends of the resonant capacitor C, wherein the emitter of the power switching tube IGBT is connected to the input end of the rectifier unit 201 and is grounded. The synchronous detection unit 40 is also used to detect the voltage at both ends of the resonant heating unit 203. The synchronous detection unit 40 includes a resonant voltage detection module 41 and a collector voltage detection module 42. The resonant voltage detection module 41 includes a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11 and a second capacitor C2. The ninth resistor R9 is connected to one end of the resonant capacitor C, and the other end of the ninth resistor R9 has a fourth node J4. One end of the tenth resistor R10 is connected to the other end of the ninth resistor R9 and is suitable for outputting the voltage at one end of the resonant heating unit 203. The other end of the tenth resistor R10 is grounded. One end of the eleventh resistor R11 is connected to the other end of the resonant capacitor C, and the other end of the eleventh resistor R11 has a fifth node J5 and is suitable for outputting the voltage at one end of the resonant heating unit 203. The voltage at the other end of the thermal unit 203, one end of the second capacitor C2 is connected to the fourth node J4, and the other end of the second capacitor C2 is connected to the fifth node J5; the collector voltage detection module 42 includes a twelfth resistor R12, a thirteenth resistor R13, a fourteenth resistor R14 and a third capacitor C3, one end of the twelfth resistor R12 is connected to the fifth node J5, the other end of the twelfth resistor R12 is connected to one end of the thirteenth resistor R13, and has a sixth node J6, the other end of the thirteenth resistor R13 is grounded, one end of the fourteenth resistor R14 is connected to the sixth node J6, the other end of the fourteenth resistor R14 is connected to one end of the third capacitor C3, and is suitable for outputting the collector voltage of the power switch tube IGBT, and the other end of the third capacitor C3 is grounded.

[0082] It should be noted that the electromagnetic heating device 200 of this embodiment can be an electromagnetic heating product such as an induction cooker, an electromagnetic rice cooker, or an electromagnetic pressure cooker.

[0083] According to the electromagnetic heating device of an embodiment of the present invention, by adopting the above-mentioned electromagnetic heating control circuit, the driving voltage of the power switch tube is controlled by the driving unit to make the power switch tube soft-turn on, and the collector voltage of the power switch tube is released to zero volts, thereby reducing the turn-on voltage and turn-on current, reducing the instantaneous loss of the power switch tube, reducing the temperature rise of the power switch tube, and thus improving the life of the power switch tube.

[0084] Corresponding to the above embodiment, the embodiment of the present invention further provides a control method for electromagnetic heating equipment. Figure 7As shown, the electromagnetic heating device 200 includes the electromagnetic heating control circuit 100 of any of the above embodiments, as shown in FIG. Figure 9 As shown, the method includes the following steps:

[0085] S101 , in response to an enable control instruction, controlling the soft drive control unit to start, so that when the drive unit drives the power switch tube to turn on, the soft drive control unit controls the power supply voltage provided to the drive unit to be lowered, so that the power switch tube is soft-turned on.

[0086] Specifically, the collector of the power switch is adapted to receive a resonant voltage. When the resonant voltage resonates to 0, the power switch turns on. At this point, the collector voltage of the power switch is 0, and the turn-on voltage, turn-on current, and turn-on loss of the power switch are relatively low. However, when the resonant parameters of the cookware used by the user are poor, the resonant voltage cannot resonate to 0, causing the collector voltage of the power switch to be greater than 0. If the power switch is turned on at this point, the turn-on voltage, turn-on current, and losses of the power switch are relatively high, resulting in a high temperature rise of the power switch. The drive unit outputs a drive voltage to the power switch to turn the power switch on or off. When the drive unit turns the power switch on, the soft drive control unit reduces the power supply voltage of the drive unit, reducing the drive voltage output by the drive unit to the drive voltage within the amplification region of the power switch, thereby placing the power switch in a linear turn-on state. The collector voltage of the power switch is slowly reduced to zero volts by the current, thereby spreading the instantaneous turn-on loss over the time the amplification region drive voltage is on, thereby reducing switching losses.

[0087] In the above embodiment, the soft drive control unit controls the drive unit to reduce the drive voltage to softly turn on the power switch tube, releases the collector voltage of the power switch tube to zero volts, reduces the turn-on voltage and turn-on current, reduces the instantaneous loss of the power switch tube, reduces the temperature rise of the power switch tube, and thus improves the life of the power switch tube.

[0088] In some embodiments, the soft drive control unit controls the reduction of the power supply voltage provided to the drive unit when the drive unit drives the power switch tube to turn on, including: the soft drive control unit divides the power supply voltage to reduce the drive voltage applied to the power switch tube by the drive unit.

[0089] Specifically, the soft drive control unit divides the power supply voltage when the power switch tube is turned on, so that the driving voltage applied to the power switch tube by the drive unit is the divided power supply voltage, thereby reducing the driving voltage of the power switch tube and placing the power switch tube in the amplification region.

[0090] In some embodiments, the soft driving control unit is disabled after the on time reaches a first preset time, so that the driving unit drives the power switch tube to enter a saturated on state based on the power supply voltage.

[0091] Specifically, after the soft drive control unit is enabled for a first preset time, the soft drive control unit stops dividing the power supply voltage, and the drive unit drives the power switch tube according to the power supply voltage, so that the power switch tube enters a saturation state.

[0092] In the above embodiment, by controlling the working state of the soft drive control unit and adjusting the magnitude of the drive voltage, the power switch tube first enters the linear turn-on state and then enters the saturation state. Compared with directly controlling the power switch tube to enter the saturation state, the turn-on loss of the power switch tube can be effectively reduced, thereby reducing the temperature rise of the power switch tube.

[0093] Furthermore, in some embodiments, the first preset time is less than the turn-on time of the power switch tube.

[0094] That is to say, the time that the power switch tube is in the soft turn-on state is shorter than the turn-on time of the power switch tube. If the power switch tube is in the soft turn-on state for a longer time, the turn-on current of the power switch tube gradually increases, and the loss of the power switch tube will also gradually increase, resulting in a higher temperature rise of the power switch tube.

[0095] In some embodiments, controlling the soft driving control unit to turn on includes: controlling the soft driving control unit to turn on in each switching cycle of the power switch tube.

[0096] It is understandable that the soft drive control unit can be enabled in each switching cycle, that is, the power switch tube is turned on in a soft turn-on manner in each switching cycle and then enters a saturation state, which can reduce the temperature rise of the power switch tube.

[0097] In some embodiments, controlling the soft driving control unit to turn on includes: controlling the soft driving control unit to turn on during a set switching cycle of the power switch tube, wherein the set switching cycle is determined based on electromagnetic heating parameters.

[0098] That is to say, the soft drive control unit is not limited to being enabled in each switching cycle, and the set switching cycle in which the soft drive control unit needs to be enabled can also be determined based on the electromagnetic heating parameters. The electromagnetic heating parameters can be the electromagnetic heating power or the electromagnetic heating demand. For example, Figure 3As shown, the soft drive control unit can be enabled within a preset time interval and during each switching cycle of the power switch tube. For example, for a 10ms heating mains envelope, the electromagnetic heating requirement is 3-6ms, and the soft drive control unit needs to be enabled. The switching cycle is set for each switching cycle between 3-6ms. At other times, the power switch tube is turned on in a hard-on manner, that is, the power switch tube directly enters a saturation state. Compared with the continuous use of the hard-on method, the temperature rise of the power switch tube is reduced, thereby extending the service life of the power switch tube and further improving the performance of the electromagnetic heating device.

[0099] In some embodiments, before controlling the soft drive control unit to turn on, the method further includes: obtaining the actual power of the electromagnetic heating device; and generating an enable control instruction when the actual power is less than a preset power threshold.

[0100] Specifically, if Figure 6 As shown, when the actual power is less than the preset power threshold, an enable control signal is output to the soft drive control unit in each switching cycle, so that the soft drive control unit is enabled to divide the power supply voltage. After a first preset time, the enable control signal is stopped, at which point the soft drive control unit stops dividing the power supply voltage. When the actual power is greater than or equal to the preset power threshold, no enable control signal is output to the soft drive control unit.

[0101] In an optional embodiment, before obtaining the actual power of the electromagnetic heating device, the electromagnetic heating device is controlled to perform heating according to a preset target power.

[0102] The technical solution of this application is further described in detail below in conjunction with specific implementation methods:

[0103] like Figure 10 As shown, the control method of the electromagnetic heating device includes the following steps:

[0104] S301, controlling the electromagnetic heating device to perform heating according to a preset target power.

[0105] S302: Obtain the actual power of the electromagnetic heating device.

[0106] S303, determine whether the actual power is less than the preset power threshold, if the actual power is less than the preset power threshold, execute step S304, if the actual power is greater than or equal to the preset power threshold, execute step S305.

[0107] S304: Generate an enabling control instruction for the soft drive control unit.

[0108] S305, disabling the soft drive control unit.

[0109] S306, determining whether a stop heating instruction is received, if a stop heating instruction is received, executing step S307, if no stop heating instruction is received, returning to step S302.

[0110] S307, controlling the electromagnetic heating device to stop heating.

[0111] In the above embodiment, the soft drive control unit is enabled according to the actual power of the electromagnetic heating device, which can effectively reduce the turn-on current of the power switch tube and improve the service life of the power switch tube; and, low-power heating technology is realized with low heating noise, thereby improving the reliability of the electromagnetic heating device.

[0112] In summary, according to the control method of the electromagnetic heating equipment according to the embodiment of the present invention, in response to the enable control instruction, the soft drive control unit is controlled to turn on. When the drive unit drives the power switch tube to turn on, the soft drive control unit controls the reduction of the power supply voltage provided to the drive unit, so that the drive voltage of the drive unit is reduced to the amplification area drive voltage of the power switch tube, so that the power switch tube is in a linear turn-on state, and the collector voltage is released to zero volts, thereby reducing the turn-on voltage and turn-on current, reducing the instantaneous loss of the power switch tube, and reducing the temperature rise of the power switch tube, thereby improving the life of the power switch tube.

[0113] Corresponding to the above embodiments, an embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the control method of the electromagnetic heating device of any of the above embodiments is implemented.

[0114] According to the computer-readable storage medium of an embodiment of the present invention, by executing a computer program of the control method of the above-mentioned electromagnetic heating equipment, the driving voltage of the power switch tube is controlled by the driving unit to make the power switch tube soft-turn on, and the collector voltage of the power switch tube is released to zero volts, thereby reducing the turn-on voltage and turn-on current, reducing the instantaneous loss of the power switch tube, reducing the temperature rise of the power switch tube, and thus improving the life of the power switch tube.

[0115] Corresponding to the above embodiment, the embodiment of the present invention further provides an electromagnetic heating device. Figure 11 As shown, the electromagnetic heating device 200 includes: a memory 210, a processor 220, and a computer program stored in the memory 210 and executable on the processor 220. When the processor 220 executes the computer program, the control method of the electromagnetic heating device of any of the aforementioned embodiments is implemented.

[0116] According to the motor controller of an embodiment of the present invention, a computer program of the control method of the above-mentioned electromagnetic heating equipment is executed by a processor, and the driving voltage of the power switch tube is controlled by the drive unit to make the power switch tube soft-turn on, and the collector voltage of the power switch tube is released to zero volts, thereby reducing the turn-on voltage and turn-on current, reducing the instantaneous loss of the power switch tube, reducing the temperature rise of the power switch tube, and thus improving the life of the power switch tube.

[0117] It should be noted that the logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing the logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other system that can fetch and execute instructions from an instruction execution system, apparatus, or device), or in conjunction with such instruction execution system, apparatus, or device. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transmit a program for use by an instruction execution system, apparatus, or device, or in conjunction with such instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection portion having one or more wires (electronic device), a portable computer disk cartridge (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and portable compact disc read-only memory (CDROM). Furthermore, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing it in another suitable manner if necessary, and then storing it in a computer memory.

[0118] It should be understood that various parts of the present invention can be implemented using hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one of the following technologies known in the art or a combination thereof can be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application-specific integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0119] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0120] In addition, the terms "first" and "second" used in the embodiments of the present invention are only used for descriptive purposes and should not be understood as indicating or implying relative importance, or implicitly indicating the number of technical features indicated in this embodiment. Therefore, the features defined by the terms "first" and "second" in the embodiments of the present invention can explicitly or implicitly indicate that the embodiment includes at least one of such features. In the description of the present invention, the word "plurality" means at least two or two or more, such as two, three, four, etc., unless otherwise clearly and specifically defined in the embodiments.

[0121] In the present invention, unless otherwise clearly specified or limited in the embodiments, the terms "installed," "connected," "connect," and "fixed" appearing in the embodiments should be understood in a broad sense. For example, the connection may be a fixed connection, a detachable connection, or an integral connection. It can also be a mechanical connection, an electrical connection, etc.; of course, it can also be a direct connection, or an indirect connection through an intermediate medium, or it can be internal communication between two elements, or an interaction between two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood based on the specific implementation.

[0122] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. An electromagnetic heating control circuit, characterized in that: include: Power switch tube; A driving unit, configured to drive the power switch tube to turn on or off; The soft driving control unit is configured to control the power supply voltage provided to the driving unit to be reduced when the driving unit drives the power switch tube to be turned on, so as to enable the power switch tube to be soft-turned on.

2. The electromagnetic heating control circuit according to claim 1, characterized in that: The soft drive control unit is enabled when the drive unit drives the power switch tube to turn on, so as to reduce the drive voltage applied to the power switch tube by the drive unit by dividing the power supply voltage.

3. The electromagnetic heating control circuit according to claim 2, characterized in that: The soft drive control unit is disabled after being enabled for a first preset time, so that the drive unit drives the power switch tube to enter a saturated on state based on the power supply voltage.

4. The electromagnetic heating control circuit according to claim 3, characterized in that: The first preset time is shorter than the turn-on time of the power switch tube.

5. The electromagnetic heating control circuit according to claim 2, characterized in that: The soft drive control unit is enabled in each switching cycle of the power switch tube.

6. The electromagnetic heating control circuit according to claim 2, characterized in that: The soft driving control unit is enabled during a set switching period of the power switch tube, wherein the set switching period is determined based on electromagnetic heating parameters.

7. The electromagnetic heating control circuit according to any one of claims 1 to 6, characterized in that: The soft drive control unit includes: a first resistor, one end of which is suitable for connecting to the driving unit; a first transistor, wherein the emitter of the first transistor is connected to the other end of the first resistor, and the collector of the first transistor is grounded; a second resistor, one end of the second resistor being connected to the base of the first transistor; A third resistor, one end of the third resistor is suitable for connecting to the power supply voltage, the other end of the third resistor is connected to the other end of the second resistor, and has a first node, the first node is suitable for receiving an enable control signal, wherein the enable control signal is used to enable the soft drive control unit.

8. The electromagnetic heating control circuit according to claim 7, characterized in that: The driving unit includes: a second triode, wherein the emitter of the second triode is grounded, and the base of the second triode is suitable for receiving the driving control signal of the power switch tube; a fourth resistor, one end of the fourth resistor being adapted to be connected to the power supply voltage, the other end of the fourth resistor being connected to the collector of the second transistor, and having a second node connected to one end of the first resistor; a third triode, wherein a base of the third triode is connected to the second node, and a collector of the third triode is connected to the power supply voltage via a fifth resistor; a fourth triode, wherein the base of the fourth triode is connected to the base of the third triode, and the collector of the fourth triode is connected to the reference ground; A sixth resistor, one end of the sixth resistor is connected to the emitter of the third transistor and has a third node, the other end of the sixth resistor is connected to the emitter of the fourth transistor, wherein the third node is suitable for connecting to the control electrode of the power switch tube.

9. The electromagnetic heating control circuit according to claim 8, characterized in that: The driving unit further includes: a seventh resistor, one end of the seventh resistor being connected to the base of the second transistor; An eighth resistor, one end of the eighth resistor is suitable for connecting to the power supply voltage, and the other end of the eighth resistor is connected to the other end of the seventh resistor to serve as a control signal receiving end of the driving unit.

10. The electromagnetic heating control circuit according to claim 1, characterized in that: Also includes: The control unit is configured to obtain the actual power of the electromagnetic heating device and output an enable control signal to the soft drive control unit when the actual power is less than a preset power threshold.

11. The electromagnetic heating control circuit according to claim 10, characterized in that: The control unit is further configured to output a driving control signal to the driving unit, so as to drive the power switch tube to be turned on or off through the driving unit.

12. An electromagnetic heating device, characterized in that: The electromagnetic heating control circuit comprises the electromagnetic heating control circuit according to any one of claims 1 to 11.

13. A control method for electromagnetic heating equipment, characterized in that: The electromagnetic heating device comprises an electromagnetic heating control circuit according to any one of claims 1 to 11, and the method comprises: In response to the enable control instruction, the soft drive control unit is controlled to be turned on so that when the drive unit drives the power switch tube to turn on, the soft drive control unit controls the power supply voltage provided to the drive unit to be reduced, so that the power switch tube is soft-turned on.

14. The method according to claim 13, characterized in that The soft drive control unit controls the reduction of the power supply voltage provided to the drive unit when the drive unit drives the power switch tube to turn on, including: The soft drive control unit divides the power supply voltage so as to reduce the drive voltage applied by the drive unit to the power switch tube.

15. The method according to claim 14, characterized in that The soft drive control unit is disabled after the on time reaches a first preset time, so that the drive unit drives the power switch tube to enter a saturated on state based on the power supply voltage.

16. The method according to claim 15, characterized in that The first preset time is shorter than the turn-on time of the power switch tube.

17. The method according to claim 13, wherein Controlling the soft drive control unit to start, including: The soft drive control unit is controlled to start in each switching cycle of the power switch tube.

18. The method according to claim 13, characterized in that Controlling the soft drive control unit to start, including: The soft drive control unit is controlled to start at a set switching cycle of the power switch tube, wherein the set switching cycle is determined based on electromagnetic heating parameters.

19. The method according to claim 13, wherein Before controlling the soft drive control unit to start, the method further includes: Obtaining the actual power of the electromagnetic heating device; When the actual power is less than a preset power threshold, the enable control instruction is generated.

20. A computer-readable storage medium, characterized in that A computer program is stored thereon, and when the computer program is executed by a processor, the control method of the electromagnetic heating device according to any one of claims 13 to 19 is implemented.

21. An electromagnetic heating device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the control method for the electromagnetic heating device according to any one of claims 13 to 19 is implemented.

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