CN216531836U

CN216531836U - Drive circuit and electromagnetic heating equipment

Info

Publication number: CN216531836U
Application number: CN202122961441.6U
Authority: CN
Inventors: 不公告发明人
Original assignee: Shenzhen H&T Intelligent Control Co Ltd
Current assignee: Shenzhen H&T Intelligent Control Co Ltd
Priority date: 2021-11-29
Filing date: 2021-11-29
Publication date: 2022-05-13
Anticipated expiration: 2031-11-29

Abstract

The utility model provides a driving circuit and electromagnetic heating equipment, which comprise a first power supply, a push-pull unit, a voltage stabilizing unit, a switch unit and a control unit, wherein the push-pull unit is connected with the switch unit; the power supply end of the push-pull unit is connected with a first power supply, the control end of the push-pull unit is used for receiving a driving signal, the output end of the push-pull unit is used for being connected with a gate pole of an I GBT, a collector of the I GBT is connected with the resonance unit, and an emitter of the I GBT is grounded; the voltage stabilizing unit and the switch unit are connected in series between the power supply end of the push-pull unit and the ground, and the control end of the switch unit is connected with the control unit; when the working power of the electromagnetic heating equipment is smaller than a first power threshold value, the control unit outputs a conducting signal to the switch unit, the voltage stabilizing unit stabilizes the voltage of a power supply end of the push-pull unit to a first voltage, and when the driving signal is a first signal, the push-pull unit outputs the first voltage to a gate pole of the I GBT, so that the I GBT works at the first voltage, the temperature rise of the power tube is reduced, the reliability is improved, the service life is prolonged, and the electromagnetic heating equipment can realize uninterrupted heating during low-power work.

Description

Drive circuit and electromagnetic heating equipment

Technical Field

The embodiment of the utility model relates to the field of household appliances, in particular to a driving circuit and electromagnetic heating equipment.

Background

The electromagnetic heating product generates eddy current at the bottom of the cooker by means of an alternating magnetic field, and the alternating magnetic field is generated by enabling a coil panel and a resonant capacitor to resonate through the on-off of a high-power device IGBT.

However, when the household induction cooker works under low power, the driving voltage of the IGBT is consistent with the driving voltage of the IGBT when the household induction cooker works under high power, but the operating frequency of the IGBT is high at the moment, so that the temperature of the IGBT rises, the IGBT needs to be cooled through intermittent heating at the moment, namely, the power tube IGBT needs to be turned on or turned off repeatedly, however, the quality of cooking food materials can be influenced by the intermittent heating mode, the voltage impact of the IGBT is turned on or off repeatedly, fatigue damage to the IGBT in different degrees can be caused, and the service life of the IGBT is shortened.

SUMMERY OF THE UTILITY MODEL

The embodiment of the utility model mainly provides a driving circuit and electromagnetic heating equipment, and when the electromagnetic heating equipment works under low power, the driving voltage of an IGBT is reduced, the temperature of the IGBT is reduced, and the electromagnetic heating equipment realizes low-power uninterrupted working heating, so that the reliability of the IGBT is improved, and the service life of the IGBT is prolonged.

In a first aspect, one technical solution adopted in the embodiments of the present invention is: provided is a drive circuit including: the device comprises a first power supply, a push-pull unit, a voltage stabilizing unit, a switch unit and a control unit; the power supply end of the push-pull unit is connected with the first power supply, the control end of the push-pull unit is used for receiving a driving signal, the output end of the push-pull unit is used for being connected with a gate pole of an IGBT, a collector of the IGBT is connected with a resonance unit of electromagnetic heating equipment, and an emitter of the IGBT is grounded; the voltage stabilizing unit and the switch unit are connected in series between a power supply end of the push-pull unit and the ground, and a control end of the switch unit is connected with the control unit; the control unit is used for outputting a conducting signal to the switch unit when the working power of the electromagnetic heating equipment is smaller than a first power threshold value; the switch unit is used for being in a conducting state according to the conducting signal so as to enable the voltage stabilizing unit to stabilize the voltage of the power supply end of the push-pull unit at a first voltage; the push-pull unit is used for outputting the first voltage to a gate pole of the IGBT and conducting the IGBT to enable the resonance unit to work when the driving signal is a first signal.

In some embodiments, the voltage stabilization unit includes a voltage stabilization diode; the cathode of the voltage stabilizing diode is respectively connected with the first power supply and the power supply end of the push-pull unit, the anode of the voltage stabilizing diode is connected with the first end of the switch unit, and the second end of the switch unit is grounded.

In some embodiments, the switching unit comprises a first switching tube; the first end of the first switch tube is connected with the anode of the voltage stabilizing diode, the second end of the first switch tube is grounded, and the third end of the first switch tube is connected with the control unit.

In some embodiments, the push-pull unit comprises a second switching tube, a third switching tube and a fourth switching tube; the first end of second switch tube is connected first power, the first end of second switch tube still is used for receiving drive signal, the second end of second switch tube is connected respectively the first end of third switch tube, the first end of fourth switch tube with first power, the third end ground connection of second switch tube, the second end of third switch tube is connected first power, the third end of third switch tube is connected respectively the gate pole of IGBT with the second end of fourth switch tube, the third end ground connection of fourth switch tube.

In some embodiments, the push-pull unit further comprises a first resistor, a second resistor, and a third resistor; the first resistor is connected between the second end of the third switching tube and the first power supply, the first end of the second resistor is connected with the first end of the second switching tube, the second end of the second resistor is connected with the first power supply, the second end of the second resistor is also used for receiving the driving signal, and the third resistor is connected between the third end of the third switching tube and the gate pole of the IGBT.

In some embodiments, the push-pull unit further comprises a fourth resistor and a fifth resistor; the fourth resistor is connected between the first power supply and the first end of the third switching tube, and the fifth resistor is connected between the first power supply and the second end of the second resistor.

In some embodiments, the driving circuit further comprises a first capacitor, and the push-pull unit further comprises a second capacitor; the first capacitor is connected between the first power supply and the ground, and the second capacitor is connected between the second end of the second switch tube and the ground.

In some embodiments, the driving circuit further comprises a sixth resistor and a seventh resistor; the sixth resistor is connected between the first power supply and the voltage stabilizing unit, and the seventh resistor is connected between the control unit and the control end of the switch unit.

In some embodiments, the driving circuit further comprises an eighth resistor; and the first end of the eighth resistor is used for connecting the gate electrode of the IGBT, and the second end of the eighth resistor is used for connecting the emitter electrode of the IGBT.

In a second aspect, an embodiment of the present invention further provides an electromagnetic heating apparatus, which includes the driving circuit according to any one of the first aspect.

The beneficial effects of the embodiment of the utility model are as follows: the present invention provides a driving circuit and an electromagnetic heating apparatus, which are distinguished from the state of the art, including a first power supply, a push-pull unit, a voltage stabilization unit, a switching unit, and a control unit; the power supply end of the push-pull unit is connected with a first power supply, the control end of the push-pull unit is used for receiving a driving signal, the output end of the push-pull unit is used for being connected with a gate pole of the IGBT, a collector of the IGBT is connected with a resonance unit of the electromagnetic heating equipment, and an emitter of the IGBT is grounded; the voltage stabilizing unit and the switch unit are connected in series between the power supply end of the push-pull unit and the ground, and the control end of the switch unit is connected with the control unit; when the working power of the electromagnetic heating equipment is smaller than the first power threshold, the control unit outputs a conducting signal to the switch unit, the switch unit is conducted, the voltage stabilizing unit stabilizes the voltage of the power supply end of the push-pull unit to a first voltage, and when the driving signal is the first signal, the push-pull unit can output the first voltage to the gate pole of the IGBT, so that the IGBT works under the first voltage, the temperature rise of the IGBT can be effectively reduced by setting the voltage value of the first voltage, the working reliability of the IGBT is improved, the service life of the IGBT is prolonged, and the electromagnetic heating equipment can realize uninterrupted heating in low-power work.

Drawings

One or more embodiments are illustrated by the accompanying figures in the drawings that correspond thereto and are not to be construed as limiting the embodiments, wherein elements/modules and steps having the same reference numerals are represented by like elements/modules and steps, unless otherwise specified, and the drawings are not to scale.

Fig. 1 is a schematic structural block diagram of a driving circuit according to an embodiment of the present invention;

fig. 2 is a schematic circuit structure diagram of a driving circuit according to an embodiment of the present invention.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the utility model, but are not intended to limit the utility model in any way. It should be noted that variations and modifications can be made by persons skilled in the art without departing from the spirit of the utility model. All falling within the scope of the present invention.

In order to facilitate an understanding of the present application, the present application is described in more detail below with reference to the accompanying drawings and specific embodiments. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

It should be noted that, if not conflicted, the various features of the embodiments of the utility model may be combined with each other within the scope of protection of the present application. In addition, although the functional blocks are divided in the device diagram, in some cases, the blocks may be divided differently from those in the device. Further, the terms "first," "second," and the like, as used herein, do not limit the data and the execution order, but merely distinguish the same items or similar items having substantially the same functions and actions.

In a first aspect, an embodiment of the present invention provides a driving circuit, referring to fig. 1, the driving circuit 100 includes: a first power supply 10, a push-pull unit 20, a voltage stabilizing unit 30, a switching unit 40, and a control unit 50.

A power supply end of the push-pull unit 20 is connected with the first power supply 10, a control end of the push-pull unit 20 is used for receiving a driving SIGNAL, an output end of the push-pull unit 20 is used for connecting a gate electrode of the IGBT200, a collector electrode of the IGBT200 is connected with the resonance unit 300 of the electromagnetic heating device, and an emitter electrode of the IGBT200 is grounded; the voltage stabilizing unit 30 and the switching unit 40 are connected in series between the power source terminal of the push-pull unit 20 and the ground, and the control terminal of the switching unit 40 is connected to the control unit 50.

The control unit 50 is configured to output a conducting signal to the switching unit 40 when the working power of the electromagnetic heating device is smaller than a first power threshold; the switching unit 40 is configured to be in a conducting state according to the conducting signal, so that the voltage stabilizing unit 30 stabilizes the voltage of the power terminal of the push-pull unit 20 at a first voltage; the push-pull unit 20 is configured to output a first voltage to a gate of the IGBT200 to turn on the IGBT200 when the driving SIGNAL is the first SIGNAL, so that the resonant unit 300 operates.

In the driving circuit, when the working power of the electromagnetic heating device is greater than or equal to the first power threshold, the control unit 50 outputs an off SIGNAL to the switching unit 40, the switching unit 40 is in an off state according to the off SIGNAL, at this time, the power supply terminal voltage of the push-pull unit 20 is the voltage value of the first power supply 10, when the driving SIGNAL of the push-pull unit 20 is the first SIGNAL, the push-pull unit 20 outputs the voltage of the first power supply 10 to the gate of the IGBT200, the IGBT200 is turned on, and the resonance unit 300 operates. When the working power of the electromagnetic heating device is less than the first power threshold, the control unit 50 outputs a conducting signal to the switching unit 40, the switching unit 40 is in a conducting state according to the conducting signal, at this time, the voltage stabilizing unit 30 stabilizes the voltage of the power source end of the push-pull unit 20 to a first voltage, and the voltage of the power source end of the push-pull unit 20 is the first voltage. It will be appreciated that the first voltage should be less than the voltage of the first power supply 10.

In the driving circuit, when the operating power of the electromagnetic heating device is different, the voltage at the power source of the push-pull unit 20 is different, and the driving SIGNAL is the first SIGNAL, the push-pull unit 20 can output the different voltage at the power source to the gate of the IGBT200, so that the IGBT200 operates at different driving voltages. Thus, by designing the value of the first voltage, when the working power of the electromagnetic heating device is smaller than the first power threshold, the IGBT200 can be operated at a smaller driving voltage, so that the temperature rise of the IGBT200 in the on-state process is effectively reduced, and thus the temperature is reduced without repeatedly turning off the IGBT200, the IGBT200 can be effectively protected, the working reliability and the service life of the IGBT200 are improved, and the electromagnetic heating device can realize uninterrupted heating in low-power operation.

In some of these embodiments, the control unit may be a microprocessor controller of the STM16, STM32 series, or any other control device that can be used to receive, process, and output data.

In some of the embodiments, the control terminal of the switch unit 40 is connected to the first output terminal of the control unit 50, and the control terminal of the push-pull unit 20 is connected to the second output terminal of the control unit 50, so that the driving signal is output by the control unit 50 at this time. In practice, the controller for outputting the driving signal may be a different controller from the control unit 50.

In some embodiments, referring to fig. 2, the voltage regulation unit 30 includes a voltage regulation diode D1. Wherein, the cathode of the zener diode D1 is connected to the first power supply 10 and the power source terminal of the push-pull unit 20, the anode of the zener diode D1 is connected to the first terminal of the switch unit 40, and the second terminal of the switch unit 40 is grounded. Thus, by selecting the zener diode D1 with different regulated voltages, the voltage level of the first voltage can be set.

In some embodiments, with continued reference to fig. 2, the switch unit 40 includes a first switch Q1. The first end of the first switch tube Q1 is connected to the anode of the zener diode D1, the second end of the first switch tube Q1 is grounded, and the third end of the first switch tube Q1 is connected to the control unit 50. Specifically, the first switching tube includes a first NPN transistor Q1, a base of the first NPN transistor Q1 is connected to the control unit 50, a collector of the first NPN transistor Q1 is connected to an anode of the zener diode D1, and an emitter of the first NPN transistor Q1 is grounded. The control unit 50 may enable the power supply terminal of the push-pull unit 20, the zener diode D1 and the ground to form a loop by controlling the conduction of the first NPN transistor Q1, so that the zener diode D1 enters an operating state, and the zener diode D1 stabilizes the voltage of the power supply terminal of the push-pull unit 20 at the first voltage, thereby changing the voltage of the power supply terminal of the push-pull unit 20. In practical applications, the first switch tube may also use a PNP transistor, a MOS transistor, a relay, or any other suitable switch device, and the limitation in this embodiment is not required herein.

In some embodiments, referring to fig. 2, the push-pull unit 20 includes a second switching tube Q2, a third switching tube Q3, and a fourth switching tube Q4. The first end of the second switching tube Q2 is connected to the first power supply 10, the first end of the second switching tube Q2 is further configured to receive a driving SIGNAL, the second end of the second switching tube Q2 is respectively connected to the first end of the third switching tube Q3, the first end of the fourth switching tube Q4 and the first power supply 10, the third end of the second switching tube Q2 is grounded, the second end of the third switching tube Q3 is connected to the first power supply 10, the third end of the third switching tube Q3 is respectively connected to the gate of the IGBT200 and the second end of the fourth switching tube Q4, and the third end of the fourth switching tube Q4 is grounded. At this time, the power source terminal of the push-pull unit 20 is the second terminal of the third switching tube Q3.

Specifically, with reference to fig. 2, the second switch includes a second NPN transistor Q2, the third switch includes a third NPN transistor Q3, and the fourth switch includes a PNP transistor Q4. The base of the second NPN transistor Q2 is connected to the first power supply 10, the base of the second NPN transistor Q2 is further configured to receive the driving SIGNAL, the collector of the second NPN transistor Q2 is connected to the base of the third NPN transistor Q3, the base of the PNP transistor Q4, and the first power supply 10, the emitter of the second NPN transistor Q2 is grounded, the collector of the third NPN transistor Q3 is connected to the first power supply 10, the emitter of the third NPN transistor Q3 is connected to the gate of the IGBT200 and the emitter of the PNP transistor Q4, and the collector of the PNP transistor Q4 is grounded. At this time, the power supply terminal of the push-pull unit is the collector of the third NPN transistor Q3.

Then, in the push-pull unit 20, when the driving SIGNAL is the first SIGNAL of the low level, the second NPN transistor Q2 is not turned on, the bases of the third NPN transistor Q3 and the PNP transistor Q4 are both in the high level state, the third NPN transistor Q3 is turned on, and the PNP transistor Q4 is not turned on, so that the third NPN transistor Q3 outputs the voltage at the second end (the voltage at the power supply terminal of the push-pull unit 20) to the gate of the IGBT200, and the IGBT200 is turned on to operate at the voltage. In practical applications, the number and types of the switching tubes included in the push-pull unit 20 can be set according to actual needs, and the high and low levels of the first signal are also flexibly set according to the specific circuit structure of the push-pull unit, which does not need to be limited in this embodiment.

In some embodiments, referring to fig. 2, the push-pull unit 20 further includes a first resistor R1, and the first resistor R1 is connected between the second end of the third switch Q3 and the first power supply 10. Specifically, the first resistor R1 is connected between the collector of the third NPN transistor Q3 and the first power supply 10. By providing the first resistor R1, the magnitude of the current flowing through the push-pull unit 20 from the voltage at the power supply terminal of the push-pull unit 20 can be limited, thereby protecting the push-pull unit 20.

In some embodiments, referring to fig. 2, the push-pull unit 20 further includes a second resistor R2, a first end of the second resistor R2 is connected to a first end of the second switch Q2, a second end of the second resistor R2 is connected to the first power source 10, and a second end of the second resistor R2 is further configured to receive the driving SIGNAL. Specifically, a first end of the second resistor R2 is connected to the base of the second NPN transistor Q2, and a second end of the second resistor R2 is connected to the first power supply 10. By providing the second resistor R2, the current outputted from the first power supply 10 to the second switch tube Q2 can be limited, so as to protect the second switch tube Q2.

In some embodiments, referring to fig. 2, the push-pull unit 20 further includes a third resistor R3. The third resistor R3 is connected between the third terminal of the third switching transistor Q3 and the gate of the IGBT 200. Specifically, the third resistor R3 is connected between the emitter of the third NPN transistor Q3 and the gate of the IGBT 200. By providing the third resistor R3, the magnitude of the current output from the push-pull unit 20 to the IGBT200 can be limited, thereby protecting the IGBT.

In some embodiments, referring to fig. 2, the push-pull unit 20 further includes a fourth resistor R4. The fourth resistor R4 is connected between the first power supply 10 and the first end of the third switch Q3. Specifically, the fourth resistor R4 is connected between the first power source 10 and the base of the third NPN transistor Q3. By providing the fourth resistor R4, the magnitude of the base current outputted from the first power supply 10 to the third NPN transistor Q3 and the PNP transistor Q4 can be limited.

In some embodiments, referring to fig. 2, the push-pull unit 20 further includes a fifth resistor R5. The fifth resistor R5 is connected between the first power source 10 and the second terminal of the second resistor R2. Through setting up fifth resistance R5, when drive signal is uncertain, can guarantee that second NPN triode Q2 switches on to guarantee that third NPN triode Q3 breaks off and PNP triode Q4 switches on, thereby let IGBT 200's gate ground, guarantee IGBT200 reliably turn off.

In some of the embodiments, the driving circuit further includes a first capacitor C1, and the push-pull unit 20 further includes a second capacitor C2. The first capacitor C1 is connected between the first power supply 10 and ground, and the second capacitor C2 is connected between the second end of the second switch tube Q2 and ground. Specifically, the second capacitor C2 is connected between the collector of the second NPN transistor Q2 and ground. Through setting up first electric capacity C1, can filter the voltage of the power end of exporting to push-pull unit 20, through setting up second electric capacity C2, can export the signal of second switch tube Q2 to third switch tube Q3 and fourth switch tube Q4 and filter, guarantee that drive circuit does not have clutter interference work, improve drive circuit's operational reliability.

In some embodiments, referring to fig. 2, the driving circuit further includes a sixth resistor R6, and the sixth resistor R6 is connected between the first power source 10 and the voltage stabilizing unit 30. Specifically, a first end of the sixth resistor R6 is connected to the first power supply 10, and a second end of the sixth resistor R6 is connected to a cathode of the zener diode D1 and a power supply terminal of the push-pull unit 20, respectively. By providing the sixth resistor R6, the magnitude of the current output from the first power supply 10 to the push-pull unit 20 can be limited.

In some embodiments, referring to fig. 2, the driving circuit further includes a seventh resistor R7, and the seventh resistor R7 is connected between the control unit 50 and the control terminal of the switch unit 40. Specifically, a first end of the seventh resistor R7 is connected to the control unit 50, and a second end of the seventh resistor R7 is connected to the base of the first NPN transistor Q1. By providing the seventh resistor R7, the magnitude of the base current outputted from the control unit 50 to the first NPN transistor Q1 can be limited.

In some of these embodiments, the driving circuit further includes an eighth resistor R8. A first terminal of the eighth resistor R8 is connected to the gate of the IGBT200, and a second terminal of the eighth resistor R8 is connected to the emitter of the IGBT 200. By providing the eighth resistor R8, the IGBT200 can be ensured to be reliably turned off.

The operation of the driving circuit provided by the embodiment of the present invention is described in detail with reference to the embodiment shown in fig. 2. In practical applications, the voltage value of the first power supply 10, the voltage value of the zener diode D1, and the first power threshold may be set according to actual needs, and there is no need to be limited in this embodiment.

In the driving circuit, when the operating power of the electromagnetic heating apparatus is greater than or equal to 1000W, the control unit 50 outputs a low-level turn-off signal to the base of the first NPN transistor Q1, and the first NPN transistor Q1 is turned off, so that the power terminal voltage of the push-pull unit 20 is the voltage value of the first power supply 10, i.e., 18V; at this time, the driving SIGNAL is a first low-level SIGNAL, the second NPN transistor Q2 is not turned on, the bases of the third NPN transistor Q3 and the PNP transistor Q4 are both in a high-level state, the third NPN transistor Q3 is turned on, the PNP transistor Q4 is not turned on, the voltage 18V of the first power supply 10 is output to the gate of the IGBT200 through the third NPN transistor Q3, the IGBT200 is turned on, and the resonance unit 300 operates.

When the working power of the electromagnetic heating device is less than 1000W, the control unit 50 outputs a high-level conducting SIGNAL to the base of the first NPN transistor Q1, the first NPN transistor Q1 is conducting, the voltage stabilizing diode D1 works in a voltage stabilizing state, the voltage of the power supply end of the push-pull unit 20 is stabilized to 10V, and the driving SIGNAL is a low-level first SIGNAL, at this time, the second NPN transistor Q2 is not conducting, the bases of the third NPN transistor Q3 and the PNP transistor Q4 are both in a high-level state, the third NPN transistor Q3 is conducting, the PNP transistor Q4 is not conducting, the 10V voltage is output to the gate of the IGBT200 through the third NPN transistor Q3, the IGBT200 is conducting, and the resonant unit 300 works.

It can be seen that, in the driving circuit, when the operating powers of the electromagnetic heating apparatuses are different, the voltages of the power source terminals of the push-pull unit 20 are different. And when the driving SIGNAL is the first SIGNAL, the push-pull unit 20 may output voltages of different power terminals to the gate of the IGBT200, so that the IGBT200 operates at different driving voltages. Therefore, when the electromagnetic heating device is smaller than 1000W, the IGBT200 can work under the driving voltage of 10V, the temperature rise of the IGBT200 in the conducting process is effectively reduced, the temperature is reduced without repeatedly turning off the IGBT200, the working reliability and the service life of the IGBT200 are improved, and the electromagnetic heating device can realize uninterrupted heating in low-power work.

In a second aspect, an embodiment of the present invention further provides an electromagnetic heating apparatus, including the driving circuit according to any one of the above embodiments. Specifically, the electromagnetic heating device may be a household induction cooker, or any other device that generates eddy current by resonance of a resonance unit such as a coil panel and a resonance capacitor to heat. In the electromagnetic heating apparatus, when the operating power of the electromagnetic heating apparatus is different, the power source terminal voltages of the push-pull units are different. When the driving signal is the first signal, the push-pull unit can output different power supply terminal voltages to the gate electrode of the IGBT, so that the IGBT works under different driving voltages. Therefore, by designing the value of the first voltage, when the electromagnetic heating device is smaller than the first power threshold value, the IGBT can work under a smaller driving voltage, the temperature rise of the IGBT in the conducting process is effectively reduced, the temperature is reduced without repeatedly switching off the IGBT, the working reliability and the service life of the IGBT are improved, and the electromagnetic heating device can realize uninterrupted heating in low-power work.

The utility model provides a driving circuit and electromagnetic heating equipment, which comprise a first power supply, a push-pull unit, a voltage stabilizing unit, a switch unit and a control unit, wherein the first power supply is connected with the push-pull unit; the power supply end of the push-pull unit is connected with a first power supply, the control end of the push-pull unit is used for receiving a driving signal, the output end of the push-pull unit is used for being connected with a gate pole of the IGBT, a collector of the IGBT is connected with a resonance unit of the electromagnetic heating equipment, and an emitter of the IGBT is grounded; the voltage stabilizing unit and the switch unit are connected in series between the power supply end of the push-pull unit and the ground, and the control end of the switch unit is connected with the control unit; when the working power of the electromagnetic heating equipment is smaller than a first power threshold value, the control unit outputs a conducting signal to the switch unit, the switch unit is conducted, the voltage stabilizing unit stabilizes the voltage of a power supply end of the push-pull unit to a first voltage, and when the driving signal is a first signal, the push-pull unit can output the first voltage to a gate pole of the IGBT, so that the IGBT works under the first voltage, the temperature rise of the IGBT can be effectively reduced by setting the voltage value of the first voltage, the working reliability of the IGBT is improved, the service life of the IGBT is prolonged, and the electromagnetic heating equipment can realize uninterrupted heating in low-power work.

It should be noted that the above-described embodiments of the apparatus are merely illustrative, where the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; within the idea of the utility model, also technical features in the above embodiments or in different embodiments may be combined, steps may be implemented in any order, and there are many other variations of the different aspects of the utility model as described above, which are not provided in detail for the sake of brevity; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A driver circuit, comprising: the device comprises a first power supply, a push-pull unit, a voltage stabilizing unit, a switch unit and a control unit;

the power supply end of the push-pull unit is connected with the first power supply, the control end of the push-pull unit is used for receiving a driving signal, the output end of the push-pull unit is used for being connected with a gate pole of an IGBT, a collector of the IGBT is connected with a resonance unit of electromagnetic heating equipment, and an emitter of the IGBT is grounded; the voltage stabilizing unit and the switch unit are connected in series between a power supply end of the push-pull unit and the ground, and a control end of the switch unit is connected with the control unit;

the control unit is used for outputting a conducting signal to the switch unit when the working power of the electromagnetic heating equipment is smaller than a first power threshold value; the switch unit is used for being in a conducting state according to the conducting signal so as to enable the voltage stabilizing unit to stabilize the voltage of the power supply end of the push-pull unit at a first voltage; the push-pull unit is used for outputting the first voltage to a gate pole of the IGBT and conducting the IGBT to enable the resonance unit to work when the driving signal is a first signal.

2. The driving circuit according to claim 1, wherein the voltage stabilization unit includes a voltage stabilization diode;

the cathode of the voltage stabilizing diode is respectively connected with the first power supply and the power supply end of the push-pull unit, the anode of the voltage stabilizing diode is connected with the first end of the switch unit, and the second end of the switch unit is grounded.

3. The driving circuit according to claim 2, wherein the switching unit comprises a first switching tube;

the first end of the first switch tube is connected with the anode of the voltage stabilizing diode, the second end of the first switch tube is grounded, and the third end of the first switch tube is connected with the control unit.

4. The driving circuit according to any one of claims 1 to 3, wherein the push-pull unit comprises a second switching tube, a third switching tube and a fourth switching tube;

the first end of second switch tube is connected first power, the first end of second switch tube still is used for receiving drive signal, the second end of second switch tube is connected respectively the first end of third switch tube, the first end of fourth switch tube with first power, the third end ground connection of second switch tube, the second end of third switch tube is connected first power, the third end of third switch tube is connected respectively the gate pole of IGBT with the second end of fourth switch tube, the third end ground connection of fourth switch tube.

5. The driving circuit according to claim 4, wherein the push-pull unit further comprises a first resistor, a second resistor, and a third resistor;

the first resistor is connected between the second end of the third switching tube and the first power supply, the first end of the second resistor is connected with the first end of the second switching tube, the second end of the second resistor is connected with the first power supply, the second end of the second resistor is also used for receiving the driving signal, and the third resistor is connected between the third end of the third switching tube and the gate pole of the IGBT.

6. The driving circuit of claim 5, wherein the push-pull unit further comprises a fourth resistor and a fifth resistor;

the fourth resistor is connected between the first power supply and the first end of the third switching tube, and the fifth resistor is connected between the first power supply and the second end of the second resistor.

7. The driving circuit of claim 4, wherein the driving circuit further comprises a first capacitor, and the push-pull unit further comprises a second capacitor;

the first capacitor is connected between the first power supply and the ground, and the second capacitor is connected between the second end of the second switch tube and the ground.

8. The driving circuit according to claim 1, wherein the driving circuit further comprises a sixth resistor and a seventh resistor;

the sixth resistor is connected between the first power supply and the voltage stabilizing unit, and the seventh resistor is connected between the control unit and the control end of the switch unit.

9. The driving circuit according to claim 1, further comprising an eighth resistor;

and the first end of the eighth resistor is used for connecting the gate electrode of the IGBT, and the second end of the eighth resistor is used for connecting the emitter electrode of the IGBT.

10. An electromagnetic heating device, characterized in that it comprises a drive circuit according to any one of claims 1-9.