Driving control circuit and cooking equipment

Abstract

The utility model provides a drive control circuit and cooking equipment. The drive control circuit comprises a first power supply; a resonance circuit; a power device; the sampling end of the first sampling circuit is connected with the first end of the resonance circuit, and the first sampling circuit is used for collecting first voltage at the first end of the resonance circuit; the sampling end of the second sampling circuit is connected with the first end of the power device, and the second sampling circuit is used for collecting second voltage at the first end of the power device; the comparator is respectively connected with the output end of the first sampling circuit and the output end of the second sampling circuit and is used for outputting a comparison result of the first voltage and the second voltage; and the controller is respectively connected with the output end of the comparator and the control end of the power device and is used for driving the power device according to the comparison result. In the process, the probability that the power device is broken down or the service life is attenuated is reduced, so that the reliability of the driving control circuit is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to circuit technical field, specifically, relate to a drive control circuit and cooking equipment. BACKGROUND

[0002] Figure 1 The schematic diagram of the single-tube electromagnetic parallel resonant circuit in the related technical scheme is shown, as Figure 1 The single-tube electromagnetic parallel resonant circuit includes rectifier bridge 102', filter capacitor 104', resonant capacitor 106', coil 108', power device 110' and microcontroller 112'.

[0003] Specifically, when the commercial power signal is rectified by the rectifier bridge, the input commercial power alternating signal becomes direct current signal, when the signal port of the microcontroller connected with the base of the power device outputs low level off signal relative to signal ground, at this time, the single-tube electromagnetic parallel resonant circuit has no power output.When the microcontroller connected with the base of the power device outputs control pulse, LC oscillation occurs on the resonant capacitor and the coil, thereby generating alternating electromagnetic field, and electromagnetic heating is realized.

[0004] Generally, the microcontroller collects the voltage signal 114' at the collector of the power device during LC resonance, compares with the fixed reference voltage of the internal comparator, when higher than the reference voltage, outputs control signal 116', turns off the power device, and stops heating or reduces power.

[0005] However, voltage fluctuation exists on the commercial power signal, when the voltage of the commercial power signal deviates from the design value, the power device 110' will bear abnormal back pressure, causing device breakdown or life attenuation.

[0006] Exemplarily, the current under different input voltages of the power grid is not the same, for example, 220V, 2200W, 10A, the protection voltage is set at about 1100V, when the commercial power fluctuates to 180V, the current is 10A, the power is only 1800W, and the C electrode voltage is relatively low, which may be only about 900V, so the effective protection cannot be achieved. UTILITY MODEL CONTENTS

[0007] The utility model aims at least to solve the technical problem that when the voltage of the commercial power signal deviates from the design value, the power device will bear abnormal back pressure, causing device breakdown or life attenuation in the prior art or related art.

[0008] Therefore, the first aspect of the utility model provides a drive control circuit.

[0009] The second aspect of the utility model provides a cooking equipment.

[0010] In view of the above, according to a first aspect of the present invention, the present invention provides a drive control circuit, comprising: a first power supply, the first power supply being a power supply that converts AC to DC; a resonant circuit, a first terminal of the resonant circuit being connected to a first DC terminal of the first power supply; a power device, a first terminal of the power device being connected to a second terminal of the resonant circuit, and a second terminal of the power device being connected to a second DC terminal of the first power supply; a first sampling circuit, the sampling terminal of the first sampling circuit being connected to the first terminal of the resonant circuit, for acquiring a first voltage at the first terminal of the resonant circuit; a second sampling circuit, the sampling terminal of the second sampling circuit being connected to the first terminal of the power device, for acquiring a second voltage at the first terminal of the power device; a comparator, connected to the output terminals of the first sampling circuit and the second sampling circuit respectively, for outputting a comparison result between the first voltage and the second voltage; and a controller, connected to the output terminal of the comparator and the control terminal of the power device respectively, for driving the power device according to the comparison result.

[0011] This invention proposes a drive control circuit, which includes a first power supply, a resonant circuit, a power device, a first sampling circuit, a second sampling circuit, a comparator, and a controller.

[0012] The first power supply, resonant circuit, power device, and controller can form a single-tube electromagnetic parallel resonant circuit. Specifically, when the controller outputs control pulses to the power device, the power device will continuously switch on and off. At this time, the resonant circuit will undergo LC resonance, thereby heating the pot of the cooking equipment.

[0013] In the above technical solution, since the first end of the resonant circuit is connected to the first DC end of the first power supply, when there is a voltage fluctuation in the AC power entering the first power supply, there will also be a corresponding voltage fluctuation at the first DC end of the first power supply. The sampling end of the first sampling circuit is connected to the first end of the resonant circuit. Therefore, the voltage at the first end of the resonant circuit, i.e. the first voltage, can characterize the voltage fluctuation of the AC power of the first power supply.

[0014] Similarly, the second sampling circuit can collect the voltage at the first terminal of the power device, which is the second voltage. The second voltage can characterize the operating voltage that the power device withstands.

[0015] The comparator can compare the first voltage and the second voltage, and then pass the comparison result to the controller so that the controller can drive the power device to work according to the comparison result.

[0016] In this process, the object compared with the voltage at the first terminal of the power device can be regarded as the protection action point. This protection action point is no longer a fixed reference voltage, but a voltage that changes dynamically with the AC power. If the AC voltage deviates from the design value, the object compared with the voltage at the first terminal of the power device will also change synchronously. At this time, the protection action point can be matched with the AC power of the first power supply. This can reduce the probability of the power device being subjected to abnormal reverse voltage, thereby reducing the probability of the power device being broken down or its lifespan being reduced, thus improving the reliability of the drive control circuit.

[0017] In the above technical solution, the first power source can be a power source having AC connection terminals and DC connection terminals.

[0018] Specifically, the AC connection terminal is used to connect to the mains power, and the DC connection terminals (first DC terminal and second DC terminal) are connected to the first terminal of the resonant circuit and the second terminal of the power device, respectively.

[0019] In some technical solutions, the first power source includes a rectifier bridge, which is used to convert alternating current (AC) into direct current (DC).

[0020] In addition, the drive control circuit proposed in this utility model has the following additional technical features.

[0021] In some technical solutions, optionally, the controller is specifically used to: drive the power device to turn off based on the second voltage being greater than the first voltage.

[0022] In this technical solution, when the second voltage is greater than the first voltage, it is considered that the voltage borne by the power device is too high. At this time, it is necessary to control the power device to turn off, so as to improve the abnormal reverse voltage borne by the power device, thereby reducing the probability of the power device being broken down or its lifespan being reduced, thus improving the reliability of the drive control circuit.

[0023] In some technical solutions, optionally, the first sampling circuit includes: M first resistors, which are connected in series, with the first terminal of the first resistor among the M first resistors connected to the first terminal of the resonant circuit, where M is a positive integer greater than or equal to 1; a second resistor, whose first terminal is connected to the second terminal of the Mth resistor among the M first resistors, the second terminal of the second resistor is grounded, and the first terminal of the second resistor is connected to the negative input terminal of the comparator; the second sampling circuit includes: N third resistors, which are connected in series, with the first terminal of the first resistor among the N third resistors connected to the first terminal of the power device, where N is a positive integer greater than or equal to 1; a fourth resistor, whose first terminal is connected to the second terminal of the Nth resistor among the N third resistors, the second terminal of the fourth resistor is grounded, and the first terminal of the fourth resistor is connected to the positive input terminal of the comparator.

[0024] In this technical solution, the first sampling circuit includes M first resistors and one second resistor. The second resistor is connected in series with the M first resistors and then connected between the first terminal of the resonant circuit and ground. Therefore, the voltage at the first terminal of the resonant circuit will form a path through the second resistor, the M first resistors and ground. At this time, a voltage divider will be formed on the second resistor and each of the first resistors. The voltage divider is proportional to the voltage at the first terminal of the resonant circuit. Therefore, after the first terminal of the second resistor is connected to the negative input terminal of the comparator, a voltage corresponding to the first voltage can be output to the comparator.

[0025] Similarly, the second sampling circuit includes N third resistors and one fourth resistor. The fourth resistor is connected in series with the N third resistors and then connected between the first terminal of the power device and ground. Therefore, the voltage at the first terminal of the power device will form a path through the fourth resistor, the N third resistors and ground. At this time, a voltage divider will be formed on the fourth resistor and each of the third resistors. The voltage divider is proportional to the voltage at the first terminal of the power device. Therefore, after the first terminal of the fourth resistor is connected to the non-inverting input terminal of the comparator, a voltage corresponding to the second voltage can be output to the comparator.

[0026] In this process, the comparator can be used to directly compare the magnitudes of the first voltage and the second voltage, and then directly output the corresponding comparison result. As a physical device, the comparator outputs the comparison result faster than software-based comparison logic, which can shorten the time required to determine the comparison result, thereby reducing the probability of power devices being damaged or having their lifespan reduced, thus improving the reliability of the drive control circuit.

[0027] In some technical solutions, the sum of the resistance values ​​of the M first resistors and the resistance values ​​of the second resistors is a first value, and the ratio of the resistance value of the second resistor to the first value is a first ratio.

[0028] The sum of the resistance values ​​of the first resistors and the resistance value of the fourth resistor is the second value. The ratio of the resistance value of the fourth resistor to the second value is the second ratio, where the first ratio is equal to the second ratio.

[0029] In the above technical solution, by selecting reasonable resistance values ​​for the first resistor, the second resistor, the third resistor, and the fourth resistor, the voltage at the first terminal of the second resistor is Vref=k·Vin, where k is a coefficient with a value between 0.002 and 0.005, and Vin is the voltage at the first terminal of the resonant circuit.

[0030] In the above technical solution, M and N can be selected based on the withstand voltage, and their values ​​can be selected according to actual usage requirements.

[0031] For example, when the withstand voltage is 100V, the value of M is at least 5.

[0032] In the above technical solution, when the second voltage is greater than the first voltage, the comparator outputs a high level, and when the controller receives the high level, it controls the power device to turn off.

[0033] In some technical solutions, optionally, the controller includes: a first switching transistor, the collector of which is connected to a second power supply; a second switching transistor, the emitter of which is connected to the emitter of the first switching transistor and the control terminal of the power device, and the collector of which is connected to the second DC terminal of the first power supply; a third switching transistor, the collector of which is connected to the base of the first switching transistor and the base of the second switching transistor, the emitter of which is grounded, and the base of which is connected to the output terminal of the comparator; and a fifth resistor, the first end of which is connected to the second power supply, and the second end of which is connected to the collector of the third switching transistor; wherein, when the second voltage is greater than the first voltage, the second and third switching transistors are in a conducting state, and the first switching transistor is in a cut-off state.

[0034] In this technical solution, the first and second switching transistors form a push-pull circuit. The conduction and cutoff of the first and second switching transistors in the push-pull circuit are controlled by the third switching transistor. The base of the third switching transistor is connected to the output terminal of the comparator. Therefore, the conduction and cutoff of the third switching transistor can be controlled according to the comparison result output by the comparator.

[0035] In the above technical solution, the fifth resistor can provide voltage to the collector of the third switch, and when the third switch is off, it can also make the push-pull circuit default to the state where the first switch is on and the second switch is off.

[0036] When the first switch is turned on and the second switch is turned off, the power device is turned on by default. At this time, the resonant circuit oscillates LC, realizing electromagnetic heating. Obviously, the technical solution of this utility model can protect the power device according to the dynamic protection action point during the electromagnetic heating process, thereby improving the reliability of the drive control circuit.

[0037] In some technical solutions, the controller may optionally include a sixth resistor connected in series between the collector of the first switching transistor and the second power supply.

[0038] In this technical solution, by setting a sixth resistor, the current during the operation of the push-pull circuit is limited, thereby reducing the heat generated by the first and second switching transistors. This extends the service life of the first and second switching transistors while reducing the power consumption of the drive control circuit.

[0039] In some technical solutions, the resistance value of the sixth resistor can be selected according to actual usage requirements; the specific value will not be elaborated here.

[0040] In some technical solutions, the controller may optionally include a seventh resistor, the first end of which is connected to the control terminal of the power device, and the second end of which is connected to the second DC terminal of the first power supply.

[0041] In this technical solution, when the power device is turned off, there will be residual charge on it. By setting a seventh resistor, the residual charge of the power device can be discharged, thereby improving the stability of the drive control circuit.

[0042] In some technical solutions, the controller may optionally include a Zener diode, the first end of which is connected to the control terminal of the power device, and the second end of which is connected to the second DC terminal of the first power supply.

[0043] In this technical solution, the Zener diode plays a role in stabilizing the voltage at the control terminal of the power device, that is, clamping the voltage at the control terminal of the power device to avoid large fluctuations in the voltage at the control terminal of the power device at the moment of conduction, which would affect the opening and closing of the power device. Obviously, the Zener diode can make the drive control circuit more stable.

[0044] In some technical solutions, the resonant circuit optionally includes: a coil, a first end of which is connected to a first DC terminal of a first power supply, and a second end of which is connected to a first terminal of a power device; and a capacitor, a first end of which is connected to the first end of the coil, and a second end of which is connected to the second end of the coil.

[0045] In this technical solution, the coil can form a resonant circuit with the capacitor, thereby radiating a high-frequency magnetic field into space to heat the cooking appliance.

[0046] According to a second aspect of the present invention, the present invention provides a cooking device comprising: a drive control circuit as described in any of the above.

[0047] In some technical solutions, the cooking equipment may optionally include one of the following: an induction cooker, a rice cooker, or an electric pressure cooker.

[0048] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0049] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0050] Figure 1 A schematic diagram of a single-tube electromagnetic parallel resonant circuit in a related technical solution is shown;

[0051] Figure 2 A schematic diagram of the drive control circuit in an embodiment of this utility model is shown.

[0052] in, Figure 1 The correspondence between the reference numerals and component names in the attached drawings is as follows:

[0053] 102' rectifier bridge, 104' filter capacitor, 106' resonant capacitor, 108' coil, 110' power device, 112' microcontroller, 114' voltage signal, 116' control signal.

[0054] in, Figure 2 The correspondence between the reference numerals and component names in the attached drawings is as follows:

[0055] 100 Drive control circuit, UDC first power supply, 102 Resonant circuit, K power device, 104 First sampling circuit, 106 Second sampling circuit, CMP comparator, 108 Controller, R1 First resistor, R2 Second resistor, R3 Third resistor, R4 Fourth resistor, Q1 First switch transistor, Q2 Second switch transistor, Q3 Third switch transistor, R5 Fifth resistor, R6 Sixth resistor, R7 Seventh resistor, D Zener diode, L coil, C capacitor, VCC Second power supply. Detailed Implementation

[0056] To better understand the above aspects, features, and advantages of this utility model, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0057] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0058] In one embodiment of this application, such as Figure 2As shown, a drive control circuit 100 is provided, including: a first power supply UDC, which is a power supply that converts AC to DC; a resonant circuit 102, the first terminal of which is connected to the first DC terminal of the first power supply UDC; a power device K, the first terminal of which is connected to the second terminal of the resonant circuit 102, and the second terminal of which is connected to the second DC terminal of the first power supply UDC; a first sampling circuit 104, the sampling terminal of which is connected to the first terminal of the resonant circuit 102, for acquiring a first voltage at the first terminal of the resonant circuit 102; a second sampling circuit 106, the sampling terminal of which is connected to the first terminal of the power device K, for acquiring a second voltage at the first terminal of the power device K; a comparator CMP, which is connected to the output terminal of the first sampling circuit 104 and the output terminal of the second sampling circuit 106, respectively, for outputting a comparison result between the first voltage and the second voltage; and a controller 108, which is connected to the output terminal of the comparator CMP and the control terminal of the power device K, respectively, for driving the power device K according to the comparison result.

[0059] This utility model proposes a drive control circuit 100, which includes a first power supply UDC, a resonant circuit 102, a power device K, a first sampling circuit 104, a second sampling circuit 106, a comparator CMP, and a controller 108.

[0060] The first power supply UDC, the resonant circuit 102, the power device K and the controller 108 can form a single-tube electromagnetic parallel resonant circuit 102. Specifically, when the controller 108 outputs control pulses to the power device K, the power device K will continuously switch on and off. At this time, the resonant circuit 102 will undergo LC resonance, thereby heating the pot of the cooking equipment.

[0061] In the above embodiment, since the first end of the resonant circuit 102 is connected to the first DC end of the first power supply UDC, when there is a voltage fluctuation in the AC power entering the first power supply UDC, there will also be a corresponding voltage fluctuation at the first DC end of the first power supply UDC. The sampling end of the first sampling circuit 104 is connected to the first end of the resonant circuit 102. Therefore, the voltage at the first end of the resonant circuit 102, that is, the first voltage, can characterize the voltage fluctuation of the AC power in the first power supply UDC.

[0062] Similarly, the second sampling circuit 106 can collect the voltage at the first terminal of the power device K, which is the second voltage. The second voltage can characterize the operating voltage that the power device K withstands.

[0063] The comparator CMP can compare the first voltage and the second voltage, and then pass the comparison result to the controller 108 so that the controller 108 can drive the power device K to work according to the comparison result.

[0064] In this process, the object compared with the voltage at the first terminal of the power device K can be regarded as the protection action point. This protection action point is no longer a fixed reference voltage, but a voltage that changes dynamically with the AC current. If the AC voltage deviates from the design value, the object compared with the voltage at the first terminal of the power device K will also change synchronously. At this time, the protection action point can be matched with the AC current of the first power supply UDC. This can reduce the probability of the power device K being subjected to abnormal reverse voltage, thereby reducing the probability of the power device K being broken down or its lifespan being reduced, thus improving the reliability of the drive control circuit 100.

[0065] In the above embodiments, the first power supply UDC may be a power supply having AC connection terminals and DC connection terminals.

[0066] Specifically, the AC connection terminal is used to connect to the mains power, and the DC connection terminals (first DC terminal and second DC terminal) are respectively connected to the first terminal of the resonant circuit 102 and the second terminal of the power device K.

[0067] In some embodiments, the first power supply UDC includes a rectifier bridge, wherein the rectifier bridge is used to convert alternating current into direct current.

[0068] In addition, the drive control circuit 100 proposed in this utility model also has the following additional technical features.

[0069] In some embodiments, optionally, the controller 108 is specifically configured to: drive the power device K to turn off based on the second voltage being greater than the first voltage.

[0070] In this embodiment, when the second voltage is greater than the first voltage, it is considered that the voltage borne by the power device K is too high. At this time, it is necessary to control the power device K to turn off, so as to improve the abnormal reverse voltage borne by the power device K, thereby reducing the probability of the power device K being broken down or its lifespan being reduced, thereby improving the reliability of the drive control circuit 100.

[0071] In some embodiments, optionally, the first sampling circuit 104 includes: M first resistors R1, the M first resistors R1 connected in series, the first end of the first resistor among the M first resistors R1 is connected to the first end of the resonant circuit 102, and M is a positive integer greater than or equal to 1; a second resistor R2, the first end of the second resistor R2 is connected to the second end of the Mth resistor among the M first resistors R1, the second end of the second resistor R2 is grounded, and the first end of the second resistor R2 is connected to the negative input terminal of the comparator CMP; the second sampling circuit 106 includes: N third resistors R3, the N third resistors R3 connected in series, the first end of the first resistor among the N third resistors R3 is connected to the first end of the power device K, and N is a positive integer greater than or equal to 1; a fourth resistor R4, the first end of the fourth resistor R4 is connected to the second end of the Nth resistor among the N third resistors R3, the second end of the fourth resistor R4 is grounded, and the first end of the fourth resistor R4 is connected to the positive input terminal of the comparator CMP.

[0072] In this embodiment, the first sampling circuit 104 includes M first resistors R1 and one second resistor R2. The second resistor R2 is connected in series with the M first resistors R1 and connected between the first terminal of the resonant circuit 102 and ground. Therefore, the voltage at the first terminal of the resonant circuit 102 will form a path through the second resistor R2, the M first resistors R1 and ground. At this time, a voltage divider will be formed on the second resistor R2 and each of the first resistors R1. The voltage divider is proportional to the voltage at the first terminal of the resonant circuit 102. Therefore, after the first terminal of the second resistor R2 is connected to the negative input terminal of the comparator CMP, a voltage corresponding to the first voltage can be output to the comparator CMP.

[0073] Similarly, the second sampling circuit 106 includes N third resistors R3 and one fourth resistor R4. The fourth resistor R4 is connected in series with the N third resistors R3 and connected between the first terminal of the power device K and ground. Therefore, the voltage at the first terminal of the power device K will form a path through the fourth resistor R4, the N third resistors R3 and ground. At this time, a voltage divider will be formed on the fourth resistor R4 and each third resistor R3. The voltage divider is proportional to the voltage at the first terminal of the power device K. Therefore, after the first terminal of the fourth resistor R4 is connected to the non-inverting input terminal of the comparator CMP, a voltage corresponding to the second voltage can be output to the comparator CMP.

[0074] In this process, the comparator CMP can be used to directly compare the magnitudes of the first voltage and the second voltage, and then directly output the corresponding comparison result. As a physical device, the comparator CMP outputs the comparison result faster than software-based comparison logic, which can shorten the time required to determine the comparison result, thereby reducing the probability of the power device K being broken down or its lifespan being reduced, thus improving the reliability of the drive control circuit 100.

[0075] In some embodiments, the sum of the resistance values ​​of the M first resistors R1 and the resistance values ​​of the second resistors R2 is a first value, and the ratio of the resistance value of the second resistor R2 to the first value is a first ratio.

[0076] The sum of the resistance values ​​of the first resistor R1 and the fourth resistor R4 is the second value. The ratio of the resistance value of the fourth resistor R4 to the second value is the second ratio, where the first ratio is equal to the second ratio.

[0077] In the above embodiment, by selecting reasonable resistance values ​​for the first resistor R1, the second resistor R2, the third resistor R3 and the fourth resistor R4, the voltage Vref at the first terminal of the second resistor R2 is Vref = k·Vin, where k is a coefficient with a value between 0.002 and 0.005, and Vin is the voltage at the first terminal of the resonant circuit 102.

[0078] Similarly, the voltage at the first terminal of the fourth resistor R4 is denoted by Vc.

[0079] In the above embodiments, M and N can be selected based on the withstand voltage, and their values ​​can be selected according to actual usage needs.

[0080] For example, when the withstand voltage is 100V, the value of M is at least 5.

[0081] In the above embodiment, when the second voltage is greater than the first voltage, the output of the comparator CMP outputs a high level, and the controller 108 controls the power device K to turn off when it receives the high level.

[0082] In some embodiments, optionally, the controller 108 includes: a first switch Q1, the collector of which is connected to a second power supply VCC; a second switch Q2, the emitter of which is connected to the emitter of the first switch Q1 and the control terminal of the power device K, and the collector of which is connected to the second DC terminal of the first power supply UDC; a third switch Q3, the collector of which is connected to the base of the first switch Q1 and the base of the second switch Q2, the emitter of which is grounded, and the base of which is connected to the output terminal of the comparator CMP; and a fifth resistor R5, the first end of which is connected to the second power supply VCC, and the second end of which is connected to the collector of the third switch Q3; wherein, when the second voltage is greater than the first voltage, the second switch Q2 and the third switch Q3 are in the on state, and the first switch Q1 is in the off state.

[0083] In this embodiment, the first switch Q1 and the second switch Q2 constitute a push-pull circuit. The conduction and cutoff of the first switch Q1 and the second switch Q2 in the push-pull circuit are controlled by the third switch Q3. The base of the third switch Q3 is connected to the output terminal of the comparator CMP. Therefore, the conduction and cutoff of the third switch Q3 can be controlled according to the comparison result output by the output terminal of the comparator CMP.

[0084] In the above embodiment, the fifth resistor R5 can provide voltage to the collector of the third switch Q3, and can also enable the push-pull circuit to default to the state where the first switch Q1 is on and the second switch Q2 is off when the third switch Q3 is off.

[0085] When the first switch Q1 is turned on and the second switch Q2 is turned off, the power device K is turned on by default. At this time, the resonant circuit 102 oscillates and realizes electromagnetic heating. Obviously, the embodiment of this utility model can protect the power device K according to the dynamic protection action point during the electromagnetic heating process, thereby improving the reliability of the drive control circuit 100.

[0086] In some embodiments, the controller 108 may optionally further include a sixth resistor R6 connected in series between the collector of the first switching transistor Q1 and the second power supply VCC.

[0087] In this embodiment, by setting a sixth resistor R6, the current during the operation of the push-pull circuit is limited, thereby reducing the heat generated during the operation of the first switch Q1 and the second switch Q2. This extends the service life of the first switch Q1 and the second switch Q2 while reducing the power consumption of the drive control circuit 100.

[0088] In some embodiments, the resistance value of the sixth resistor R6 can be selected according to actual usage needs, and its specific value will not be elaborated here.

[0089] In some embodiments, the controller 108 may optionally further include a seventh resistor R7, the first end of which is connected to the control terminal of the power device K, and the second end of which is connected to the second DC terminal of the first power supply UDC.

[0090] In this embodiment, when the power device K is turned off, there will be residual power on it. By setting a seventh resistor R7, the residual power of the power device K can be discharged, thereby improving the stability of the drive control circuit 100.

[0091] In some embodiments, the controller 108 may optionally further include a Zener diode D, the first end of which is connected to the control terminal of the power device K, and the second end of which is connected to the second DC terminal of the first power supply UDC.

[0092] In this embodiment, the Zener diode D is used to stabilize the voltage at the control terminal of the power device K, that is, to clamp the voltage at the control terminal of the power device K, so as to avoid large fluctuations in the voltage at the control terminal of the power device K at the moment of conduction, which would affect the opening and closing of the power device K. Obviously, the Zener diode D can make the drive control circuit 100 more stable.

[0093] In some embodiments, the resonant circuit 102 may optionally include: a coil L, a first end of which is connected to a first DC terminal of a first power supply UDC, and a second end of which is connected to a first terminal of a power device K; and a capacitor C, a first end of which is connected to a first end of the coil L, and a second end of which is connected to a second end of the coil L.

[0094] In this embodiment, the coil L can form a resonant circuit 102 with the capacitor C, thereby radiating a high-frequency magnetic field into space to heat the cooking appliance.

[0095] In one embodiment, the comparator is integrated into the controller.

[0096] Specifically, a comparator is added to the controller to detect the input voltage after mains rectification, replacing the existing fixed reference voltage protection mechanism.

[0097] Based on this, the drive control circuit mainly includes the following modules:

[0098] 1. Voltage sampling module: It consists of a first resistor R1 and a second resistor R2. It collects the mains input voltage Vin in real time through a resistor voltage divider network. The number of first resistors R1 is selected based on the withstand voltage (e.g., if the withstand voltage is 100V, then at least 5 resistors should be selected).

[0099] 2. Adaptive reference unit: The sampling voltage sampling module's scaling circuit generates a dynamic reference voltage Vref = k·Vin (k is generally designed to be 0.002-0.005).

[0100] Intelligent comparator module: configured as a window comparator structure, its reference terminal is connected to the mains sampling unit, and it simultaneously acquires the collector voltage signal Vc of the power device at LC resonance (composed of the voltage divider of the third resistor R3 and the fourth resistor), and compares the terminal voltage Vce of the power device in real time.

[0101] Protection execution unit: When Vce>Vref, a protection signal is triggered, driving the logic circuit to control the drive pulse of the power device.

[0102] By using a dynamic threshold adjustment mechanism, the protection reference threshold of the collector voltage of the power device is adaptively adjusted. Without affecting reliability or adding circuitry, different protection voltages can be applied to different voltages, achieving the following effects:

[0103] 1. Adaptive characteristics: The protection threshold is linearly adjusted with the mains voltage (e.g., Vref = 0.99V at 220V, Vref = 0.8V at 180V);

[0104] 2. Improved reliability and compatibility: By dynamically adjusting the comparator threshold, when the mains voltage fluctuates by ±20%, the reverse stress of the power device is effectively reduced by 20% at -20% low voltage, and the power compatibility at high voltage is improved by 10%.

[0105] In some embodiments, the present invention provides a cooking device comprising: a drive control circuit as described above.

[0106] In this embodiment, a cooking device is proposed, wherein the cooking device includes a drive control circuit, and the drive control circuit includes a first power supply, a resonant circuit, a power device, a first sampling circuit, a second sampling circuit, a comparator, and a controller.

[0107] The first power supply, resonant circuit, power device, and controller can form a single-tube electromagnetic parallel resonant circuit. Specifically, when the controller outputs control pulses to the power device, the power device will continuously switch on and off. At this time, the resonant circuit will undergo LC resonance, thereby heating the pot of the cooking equipment.

[0108] In the above embodiment, since the first end of the resonant circuit is connected to the first DC end of the first power supply, when there is a voltage fluctuation in the AC power entering the first power supply, there will also be a corresponding voltage fluctuation at the first DC end of the first power supply. The sampling end of the first sampling circuit is connected to the first end of the resonant circuit. Therefore, the voltage at the first end of the resonant circuit, i.e. the first voltage, can characterize the voltage fluctuation of the AC power of the first power supply.

[0109] Similarly, the second sampling circuit can collect the voltage at the first terminal of the power device, which is the second voltage. The second voltage can characterize the operating voltage that the power device withstands.

[0110] The comparator can compare the first voltage and the second voltage, and then pass the comparison result to the controller so that the controller can drive the power device to work according to the comparison result.

[0111] In this process, the object compared with the voltage at the first terminal of the power device can be regarded as the protection action point. This protection action point is no longer a fixed reference voltage, but a voltage that changes dynamically with the AC power. If the AC voltage deviates from the design value, the object compared with the voltage at the first terminal of the power device will also change synchronously. At this time, the protection action point can be matched with the AC power of the first power supply. This can reduce the probability of the power device being subjected to abnormal reverse voltage, thereby reducing the probability of the power device being broken down or its lifespan being reduced, thus improving the reliability of the drive control circuit.

[0112] In some embodiments, the cooking equipment may optionally include one of the following: an induction cooker, a rice cooker, or an electric pressure cooker.

[0113] In this embodiment, the induction cooker using the above-mentioned drive control circuit can generate a corresponding comparison value based on the dynamically changing voltage of the AC power, which is the protection action point mentioned above. If the AC power voltage deviates from the design value, the object being compared with the voltage at the first terminal of the power device will also change synchronously. At this time, the protection action point can be matched with the AC power of the first power supply. This can reduce the probability of the power device being subjected to abnormal reverse voltage, thereby reducing the probability of the power device being damaged or its lifespan being reduced, thus improving the reliability of the induction cooker.

[0114] Furthermore, the rice cooker using the aforementioned drive control circuit can generate a corresponding comparison value based on the dynamically changing voltage of the AC power, which is the protection action point mentioned earlier. If the AC power voltage deviates from the design value, the object being compared with the voltage at the first terminal of the power device will also change synchronously. At this time, the protection action point can be matched with the AC power of the first power supply. This reduces the probability of the power device being subjected to abnormal reverse voltage, thereby reducing the probability of the power device being damaged or its lifespan being reduced, thus improving the reliability of the rice cooker.

[0115] Similarly, an electric pressure cooker using the above-mentioned drive control circuit can generate a corresponding comparison value based on the dynamically changing voltage of the AC power, which is the protection action point mentioned earlier. If the AC power voltage deviates from the design value, the object being compared with the voltage at the first terminal of the power device will also change synchronously. At this time, the protection action point can be matched with the AC power of the first power supply. This reduces the probability of the power device being subjected to abnormal reverse voltage, thereby reducing the probability of the power device being damaged or its lifespan being reduced, thus improving the reliability of the electric pressure cooker.

[0116] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the textual description of this utility model, unless otherwise stated, "multiple" means two or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0117] In the textual description of this utility model, it is understood that, unless explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection between two components or an indirect connection between two components through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0118] In the claims, description, and drawings of this utility model, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this utility model. In the claims, description, and drawings of this utility model, the illustrative expressions 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 one or more embodiments or examples.

[0119] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A drive control circuit, characterized in that, include: The first power source is a power source that converts alternating current (AC) to direct current (DC). A resonant circuit, wherein the first terminal of the resonant circuit is connected to the first DC terminal of the first power supply; A power device, wherein a first terminal of the power device is connected to a second terminal of the resonant circuit, and a second terminal of the power device is connected to a second DC terminal of the first power supply; A first sampling circuit, wherein the sampling terminal of the first sampling circuit is connected to the first terminal of the resonant circuit, is used to acquire the first voltage at the first terminal of the resonant circuit; The second sampling circuit has its sampling terminal connected to the first terminal of the power device, and is used to acquire the second voltage at the first terminal of the power device. A comparator is connected to the output terminals of the first sampling circuit and the second sampling circuit, respectively, and is used to output the comparison result between the first voltage and the second voltage; The controller is connected to the output of the comparator and the control terminal of the power device, respectively, and is used to drive the power device according to the comparison result.

2. The drive control circuit according to claim 1, characterized in that, The controller is specifically used for: The power device is driven to turn off based on the fact that the second voltage is greater than the first voltage.

3. The drive control circuit according to claim 1, characterized in that, The first sampling circuit includes: M first resistors are connected in series, and the first terminal of the first resistor among the M first resistors is connected to the first terminal of the resonant circuit. M is a positive integer greater than or equal to 1. The second resistor has its first end connected to the second end of the Mth resistor among the M first resistors, and its second end is grounded. The first end of the second resistor is connected to the negative input terminal of the comparator. The second sampling circuit includes: N third resistors are connected in series, and the first terminal of the first resistor among the N third resistors is connected to the first terminal of the power device. N is a positive integer greater than or equal to 1. The fourth resistor has its first end connected to the second end of the Nth resistor among the N third resistors, its second end grounded, and its first end connected to the non-inverting input of the comparator.

4. The drive control circuit according to claim 3, characterized in that, The controller includes: The first switching transistor has its collector connected to a second power supply. The second switching transistor has its emitter connected to the emitter of the first switching transistor and the control terminal of the power device, and its collector connected to the second DC terminal of the first power supply. The collector of the third switch is connected to the base of the first switch and the base of the second switch, the emitter of the third switch is grounded, and the base of the third switch is connected to the output terminal of the comparator. The fifth resistor has its first end connected to the second power supply and its second end connected to the collector of the third switching transistor. When the second voltage is greater than the first voltage, the second and third switching transistors are in the on state, and the first switching transistor is in the off state.

5. The drive control circuit according to claim 4, characterized in that, The controller also includes: The sixth resistor is connected in series between the collector of the first switching transistor and the second power supply.

6. The drive control circuit according to claim 4, characterized in that, The controller also includes: The seventh resistor has its first end connected to the control terminal of the power device and its second end connected to the second DC terminal of the first power supply.

7. The drive control circuit according to claim 4, characterized in that, The controller also includes: A Zener diode, the first end of which is connected to the control terminal of the power device, and the second end of which is connected to the second DC terminal of the first power supply.

8. The drive control circuit according to claim 1, characterized in that, The resonant circuit includes: A coil, wherein a first end of the coil is connected to a first DC terminal of the first power supply, and a second end of the coil is connected to a first terminal of the power device; A capacitor, wherein a first end of the capacitor is connected to a first end of the coil, and a second end of the capacitor is connected to a second end of the coil.

9. A cooking device, characterized in that, include: The drive control circuit as described in any one of claims 1 to 8.

10. The cooking apparatus according to claim 9, characterized in that, The cooking equipment includes one of the following: Induction cooker, rice cooker, electric pressure cooker.

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