CN107635299B - Electromagnetic heating cooking system and driving chip of power switch tube thereof - Google Patents
Electromagnetic heating cooking system and driving chip of power switch tube thereof Download PDFInfo
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- CN107635299B CN107635299B CN201610571898.7A CN201610571898A CN107635299B CN 107635299 B CN107635299 B CN 107635299B CN 201610571898 A CN201610571898 A CN 201610571898A CN 107635299 B CN107635299 B CN 107635299B
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Abstract
The invention discloses an electromagnetic heating cooking system and a driving chip of a power switch tube thereof, wherein the driving chip comprises: the current signal receiving end is connected with the current sampling unit and used for receiving a current sampling signal generated by the current sampling unit according to the current flowing through the power switch tube; the signal amplification unit is connected with the current signal receiving end and is used for amplifying the current sampling signal; the overcurrent protection unit is connected with the signal amplification unit and generates an overcurrent protection signal according to the amplified current sampling signal; the control signal receiving end is connected with the control chip and receives the control signal output by the control chip; and the driving unit is respectively connected with the power switch tube, the control signal receiving end and the overcurrent protection unit and is used for driving the power switch tube to be switched on or switched off according to the control signal and driving the power switch tube to be switched off when receiving the overcurrent protection signal. Therefore, an overcurrent protection function is integrated in the driving chip, and the power switch tube can be prevented from being burnt due to overlarge current.
Description
Technical Field
The invention relates to the technical field of electric appliances, in particular to a driving chip of a power switch tube in an electromagnetic heating cooking system and the electromagnetic heating cooking system with the driving chip.
Background
In an electromagnetic heating device in the related art, such as an electromagnetic oven, a constantan wire is generally connected in series between an E pole of an IGBT and a ground, an operating current signal of the IGBT is converted into a voltage signal through the constantan wire, and then an operational amplifier built in a main control chip amplifies the voltage signal and performs AD sampling to obtain a current AD value of the IGBT. Meanwhile, the main control chip judges whether the current exceeds a limit value according to the current AD value, and enters an overcurrent protection processing program when the current exceeds the limit value.
However, the related art has a disadvantage that the main control chip performs corresponding software filtering processing when reading the current AD value, for example, a filtering method of summing for multiple times to calculate an average value is adopted, so that the overcurrent state is judged by software in a manner of reading the AD value, and the overcurrent judgment is inaccurate and untimely.
Disclosure of Invention
The present invention is directed to solving, at least to some extent, one of the technical problems in the related art. Therefore, an object of the present invention is to provide a driving chip for a power switch tube in an electromagnetic heating cooking system, which can control the power switch tube to be turned off in time when an overcurrent occurs through an internal integrated circuit, so as to prevent the power switch tube from being burnt due to the overcurrent.
Another object of the present invention is to provide an electromagnetic heating cooking system.
In order to achieve the above object, an embodiment of the present invention provides a driving chip for a power switch in an electromagnetic heating cooking system, including: the current signal receiving end is connected with the current sampling unit to receive a current sampling signal generated by the current sampling unit according to the current flowing through the power switch tube; the signal amplification unit is connected with the current signal receiving end so as to amplify the current sampling signal and output the amplified current sampling signal; the overcurrent protection unit is connected with the signal amplification unit so as to generate an overcurrent protection signal according to the amplified current sampling signal; the control signal receiving end is connected with the control chip to receive the control signal output by the control chip; the driving unit is respectively connected with the power switch tube, the control signal receiving end and the overcurrent protection unit, and is used for driving the power switch tube to be switched on or switched off according to the control signal and driving the power switch tube to be switched off when receiving the overcurrent protection signal.
According to the driving chip of the power switch tube in the electromagnetic heating cooking system provided by the embodiment of the invention, the current signal receiving end is used for receiving the current sampling signal generated by the current sampling unit according to the current flowing through the power switch tube, the control signal output by the control chip is received by the control signal receiving end, then the signal amplifying unit is used for amplifying the current sampling signal, the overcurrent protection unit is used for generating the overcurrent protection signal according to the amplified current sampling signal, and the driving unit is used for driving the power switch tube to be switched on or off according to the control signal and driving the power switch tube to be switched off when receiving the overcurrent protection signal. Therefore, an overcurrent protection function is integrated in the driving chip, the power switch tube can be turned off in time when overcurrent faults occur, and the power switch tube is prevented from being burnt due to overlarge current. Moreover, the current sampling signal amplification function is integrated in the driving chip, so that the current sampling signal is amplified firstly and then transmitted, and compared with the mode of amplifying the current sampling signal firstly in transmission and then in transmission in the related technology, the stability is high, and the electromagnetic interference is not easy to generate.
Specifically, the signal amplification unit includes: the positive input end of the operational amplifier is connected with the current signal receiving end; one end of the first resistor is connected with the negative input end of the operational amplifier, and the other end of the first resistor is grounded; and one end of the second resistor is connected with the negative input end of the operational amplifier, the other end of the second resistor is connected with the output end of the operational amplifier and is provided with a first node, and the first node is connected with the overcurrent protection unit.
Specifically, the overcurrent protection unit includes: and the positive input end of the comparator is connected with the signal amplification unit, the negative input end of the comparator is connected with the reference voltage supply unit, and the output end of the comparator is connected with the driving unit.
Further, the overcurrent protection unit further includes: one end of the third resistor is connected with a first preset power supply; and one end of the first capacitor is connected with the other end of the third resistor, the other end of the first capacitor is grounded, a second node is arranged between the first capacitor and the third resistor, and the second node is connected with the output end of the comparator.
The reference voltage providing unit comprises a fourth resistor and a fifth resistor which are connected in series, one end of the fourth resistor and one end of the fifth resistor which are connected in series are connected with a first preset power supply, the other end of the fourth resistor and the other end of the fifth resistor which are connected in series are grounded, a third node is arranged between the fourth resistor and the fifth resistor which are connected in series, and the third node is connected with a negative input end of the comparator.
Specifically, the power switch tube is an IGBT, a C pole of the IGBT is connected to the resonant heating circuit, an E pole of the IGBT is grounded, and a G pole of the IGBT is connected to the driving unit.
Specifically, the current sampling unit comprises a sampling resistor, the sampling resistor is connected between the E pole of the IGBT and the ground, and a fourth node between the sampling resistor and the E pole of the IGBT is connected to the current signal receiving terminal.
Specifically, the current sampling unit further includes a sixth resistor and a second capacitor, the sixth resistor is connected between the fourth node and the current signal receiving terminal, one end of the second capacitor is connected to the current signal receiving terminal, and the other end of the second capacitor is grounded.
Specifically, the driving unit includes: the signal processor is connected with the control signal receiving end and the overcurrent protection unit respectively and is used for processing the control signal and the overcurrent protection signal to output a processed signal; and the driving circuit is connected with the signal processor and the power switch tube, and drives the power switch tube according to the processed signal.
Specifically, the control signal receiving end includes a PPG signal end for receiving a PPG signal and a voltage control end for receiving a voltage control signal, wherein, when the signal processor does not receive the over-current protection signal, the driving circuit outputs a driving signal to the power switching tube according to the PPG signal to drive the power switching tube to be turned on or off, and adjusts a voltage amplitude of the driving signal according to the voltage control signal to enable the power switching tube to work in an amplification state or a saturation conduction state.
More specifically, when the electromagnetic heating cooking system is in a starting stage, the signal processor adjusts the voltage amplitude of the driving signal to be a first preset voltage, so that the power switch tube works in an amplifying state.
Or when the electromagnetic heating cooking system is in a starting stage, the signal processor adjusts the voltage amplitude of the driving signal to be a step voltage switched between a first preset voltage and a second preset voltage, so that the power switch tube is correspondingly switched between an amplification state and a saturation conduction state.
In order to achieve the above object, in another aspect, the present invention provides an electromagnetic heating cooking system, which includes the driving chip of the power switch tube.
According to the electromagnetic heating cooking system provided by the embodiment of the invention, the performance of the electromagnetic heating cooking system can be improved through the driving chip of the power switch tube.
Drawings
Fig. 1 is a block diagram illustrating a driving chip of a power switch tube in an electromagnetic heating cooking system according to an embodiment of the present invention;
FIG. 2 is a schematic circuit diagram of a driver chip for a power switch in an electromagnetic heating cooking system according to an embodiment of the present invention;
FIG. 3 is a schematic circuit diagram of an electromagnetic heating cooking system according to one embodiment of the present invention;
FIG. 4 is a block diagram of a driver chip for a power switch in an electromagnetic heating cooking system according to an embodiment of the present invention;
fig. 5 is a waveform diagram illustrating a driving signal of a driving chip of a power switching tube in an electromagnetic heating cooking system according to an embodiment of the present invention;
fig. 6 is a waveform diagram illustrating a driving signal of a driving chip of a power switching tube in an electromagnetic heating cooking system according to another embodiment of the present invention;
fig. 7 is a waveform diagram illustrating a driving signal of a driving chip of a power switching tube in an electromagnetic heating cooking system according to another embodiment of the present invention; and
fig. 8 is an enlarged schematic view of the step voltage in fig. 7.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.
The following describes a driving chip of a power switch tube in an electromagnetic heating cooking system and the electromagnetic heating cooking system according to an embodiment of the present invention with reference to the drawings.
Fig. 1 is a block diagram illustrating a driving chip of a power switch tube in an electromagnetic heating cooking system according to an embodiment of the present invention. As shown in fig. 1, a driving chip 100 of a power switch in the electromagnetic heating cooking system includes: the current protection circuit comprises a current signal receiving end 11, a signal amplifying unit 12, an overcurrent protection unit 13, a control signal receiving end 14 and a driving unit 15.
The current signal receiving terminal 11 is connected to the current sampling unit 200 to receive a current sampling signal CUR-IN generated by the current sampling unit 200 according to the current flowing through the power switch tube 300; the signal amplifying unit 12 is connected with the current signal receiving terminal 11 to amplify the current sampling signal and output an amplified current sampling signal CUR-OUT; the overcurrent protection unit 13 is connected with the signal amplification unit 12 to generate an overcurrent protection signal according to the amplified current sampling signal CUR-OUT; the control signal receiving end 14 is connected to the control chip 400 to receive the control signal output by the control chip 400; the driving unit 15 is respectively connected to the power switch tube 300, the control signal receiving terminal 14 and the overcurrent protection unit 13, and the driving unit 15 is configured to drive the power switch tube 300 to be turned on or off according to the control signal and drive the power switch tube 300 to be turned off when receiving the overcurrent protection signal.
That is, the driving chip 100 according to the embodiment of the present invention has a current sampling signal amplifying function and an overcurrent protection function, while having a driving function. Specifically, the driving unit 15 may generate the driving signal DRIVE according to the control signal, and output the driving signal DRIVE to the control electrode of the power switch tube 300 to DRIVE the power switch tube 300 to be turned on or off. IN the process that the driving unit 15 DRIVEs the power switch tube 300 according to the control signal, the signal amplifying unit 12 amplifies the current sampling signal CUR-IN and outputs the amplified current sampling signal CUR-OUT to the overcurrent protection unit 13, when the overcurrent protection unit 13 judges that the power switch tube 300 is IN an overcurrent state according to the amplified current sampling signal CUR-OUT, the overcurrent protection unit 13 outputs an overcurrent protection signal, such as a high level signal, to the driving unit 15, and the driving unit 15 timely turns off the power switch tube 300 to stop outputting the driving signal DRIVE, thereby preventing the power switch tube from being burnt due to overcurrent.
In addition, as shown in fig. 1, the signal amplifying unit 12 may also be connected to the control chip 400 to send the amplified current sampling signal CUR-OUT to the control chip 400, so that the control chip 400 may receive the amplified current sampling signal CUR-OUT from the signal amplifying unit 12, thereby implementing current signal acquisition, and the current sampling signal may be amplified first and then transmitted, which is more stable than the first transmission and then amplification in the related art, and is less prone to electromagnetic interference.
In one embodiment of the present invention, as shown in fig. 2, the signal amplifying unit 12 includes: an operational amplifier AMP, a first resistor R1, and a second resistor R2.
Wherein, the positive input end of the operational amplifier AMP is connected with the current signal receiving end 11; one end of the first resistor R1 is connected to the negative input terminal of the operational amplifier AMP, and the other end of the first resistor R1 is grounded; one end of the second resistor R2 is connected to the negative input terminal of the operational amplifier AMP, and the other end of the second resistor R2 is connected to the output terminal of the operational amplifier AMP and has a first node connected to the overcurrent protection unit 13. In addition, the first node may be further connected to the control chip 400.
Specifically, the signal amplifying unit 12 may be composed of an operational amplifier AMP, a first resistor R1, and a second resistor R2, and the signal amplification ratio of the signal amplifying unit 12 is (R2+ R1)/R1. That is, the voltage of the amplified current sampling signal CUR-OUT may be (R2+ R1)/R1 times the voltage of the current sampling signal CUR-IN.
In an embodiment of the present invention, as shown in fig. 2, the overcurrent protection unit 13 includes: a comparator CMP, wherein a positive input terminal of the comparator CMP is connected to the signal amplifying unit 12, i.e., the first node, a negative input terminal of the comparator CMP is connected to the reference voltage providing unit 16, and an output terminal of the comparator CMP is connected to the driving unit 15 as an output terminal P1 of the overcurrent protecting unit 13.
Further, as shown in fig. 2, the overcurrent protection unit 13 further includes: a third resistor R3 and a first capacitor C1. One end of the third resistor R3 is connected with a first preset power supply VCC; one end of the first capacitor C1 is connected to the other end of the third resistor R3, the other end of the first capacitor C1 is grounded, a second node is provided between the first capacitor C1 and the third resistor R3, and the second node is connected to the output terminal of the comparator CMP.
More specifically, as shown in fig. 2, the reference voltage providing unit 16 includes a fourth resistor R4 and a fifth resistor R5 connected in series, one end of the fourth resistor R4 and one end of the fifth resistor R5 connected in series are connected to the first preset power VCC, the other end of the fourth resistor R4 and the other end of the fifth resistor R5 connected in series are connected to ground, a third node is provided between the fourth resistor R4 and the fifth resistor R5 connected in series, and the third node is connected to the negative input terminal of the comparator CMP.
That is, the overcurrent protection unit 13 compares the amplified current sampling signal CUR-OUT with the reference voltage signal Vref of the reference voltage providing unit 16. The voltage of the reference voltage signal Vref is obtained by dividing the voltage of the fourth resistor R4 and the fifth resistor R5, when the voltage of the CUR _ OUT is greater than the voltage of Vref, the output end P1 of the comparator CMP outputs a high level, the driving unit 15 judges that the power switch tube 300 is in an overcurrent state, the driving unit 15 turns off the power switch tube 300 in time, and the driving signal DRIVE is stopped from being output, so that the power switch tube is prevented from being burnt due to overcurrent; when the voltage of the CUR _ OUT is less than or equal to the voltage of Vref, the output terminal P1 of the comparator CMP outputs a low level, and the driving unit 15 determines that the power switch tube 300 is not in an overcurrent state, and normally drives the power switch tube 300 to turn on or off.
Specifically, in one embodiment of the present invention, as shown in fig. 3, the power switch 300 is an IGBT, a C pole of the IGBT is connected to the resonant heating circuit 500, an E pole of the IGBT is grounded, and a G pole of the IGBT is connected to the driving unit 15. The resonant heating circuit 500 may include a resonant capacitor CX1 and a heating coil L1 which are connected in parallel, one end of the resonant capacitor CX1 and one end of the heating coil L1 which are connected in parallel are connected to one end of a filter inductor L2, and the other end of the resonant capacitor CX1 and the other end of the heating coil L1 which are connected in parallel are connected to a C pole of the IGBT; the other end of filter inductance L2 links to each other with supply circuit 600, and one end of filter capacitance CX2 links to each other with the one end of filter inductance L2, and the other end of filter capacitance CX2 is ground connection.
Furthermore, the G pole of the IGBT is also connected with the cathode of a voltage regulator tube ZD, the anode of the voltage regulator tube ZD is grounded, and the voltage regulator tube ZD is connected with a seventh resistor R7 in parallel.
That is, the output terminal of the driving unit 15 is connected to the control electrode of the power switch tube 300, i.e., the G electrode of the IGBT, to drive the IGBT to turn on or off, and the zener diode ZD and the pull-down resistor, i.e., the seventh resistor R7, are also connected to the output terminal of the driving unit 15.
Specifically, in an embodiment of the present invention, as shown in fig. 3, the current sampling unit 300 includes a sampling resistor RC, the sampling resistor RC is connected between the E pole of the IGBT and the ground, and a fourth node between the sampling resistor RC and the E pole of the IGBT is connected to the current signal receiving terminal 11.
Further, the current sampling unit 11 further includes a sixth resistor R6 and a second capacitor C2, the sixth resistor R6 is connected between the fourth node and the current signal receiving terminal 11, one end of the second capacitor C2 is connected to the current signal receiving terminal 11, and the other end of the second capacitor C2 is grounded.
More specifically, the sampling resistor RC may be a constantan wire, the sampling resistor RC converts a current signal flowing through the IGBT into a voltage signal, i.e., a current sampling signal CUR _ IN, and the sixth resistor R6 and the second capacitor C2 constitute a filter circuit to filter the current sampling signal CUR _ IN.
Therefore, in practice, the driving chip is close to the current sampling unit 200, such as a constantan wire, the resistance value of the constantan wire is relatively small, and the current sampling signal is a small signal, and the current sampling signal amplification function is integrated in the driving chip 100 in the embodiment of the invention, so that the current sampling signal is amplified first and then transmitted, which is more stable than the current sampling signal in the related art which is transmitted first and then amplified, and is not easily subjected to electromagnetic interference. Meanwhile, an overcurrent protection function is integrated in the driving chip 100, and when the power switch tube is in an overcurrent state, the power switch tube can be turned off in time, so that the power switch tube is prevented from being burnt due to overlarge current.
In addition, due to the filter capacitor CX2, the power switch tube 300, for example, an IGBT, has a hard turn-on phenomenon in a start-up stage, and a turn-on voltage may reach 310V (220V × 3.14), which further causes a very large inrush current, which is as high as 150A or more, and easily causes the power switch tube to be burned out. Based on this, the driving unit 15 of the embodiment of the present invention adopts low voltage driving in the starting stage, so as to reduce the pulse current at the starting moment of the power switch tube.
Specifically, in one embodiment of the present invention, as shown in fig. 4, the driving unit 15 includes: a signal processor 151 and a driving circuit 152.
The signal processor 151 is connected to the control signal receiving terminal 14 and the overcurrent protection unit 13, respectively, and the signal processor 151 is configured to process the control signal and the overcurrent protection signal to output a processed signal; the driving circuit 152 is connected to the signal processor 151 and the power switch 300, and the driving circuit 152 drives the power switch 300 according to the processed signal.
Also, as shown in fig. 3 and 4, the driving chip 100 may be supplied with a supply voltage from the power module 700, and specifically, the power module 700 may supply a first preset voltage VCC, for example, 5V, to the overcurrent protection unit 13 and supply a second preset voltage VDD, for example, 18V, to the driving circuit 152.
Specifically, as shown IN fig. 3 and 4, the control signal receiving terminal 14 includes a PPG signal terminal 142 for receiving a PPG signal and a voltage control terminal 141 for receiving a voltage control signal IN2, wherein when the signal processor 151 does not receive the over-current protection signal, the driving circuit 152 outputs a driving signal to the power switch tube 300 according to the PPG signal to drive the power switch tube 300 to be turned on or off, and adjusts a voltage amplitude of the driving signal according to the voltage control signal IN2, so that the power switch tube 300 operates IN an amplification state or a saturation conduction state.
Specifically, when the signal processor 151 receives the overcurrent protection signal, and masks the PPG signal and the voltage control signal IN2, the signal processor 151 controls the driving circuit 152 to output the turn-off driving signal to the power switch tube 300 to drive the power switch tube 300 to turn off. As shown in fig. 6, when the output terminal P1 of the overcurrent protection unit outputs a high level, the driving signal DRIVE is always in a low level state, that is, when the power switch tube 300 is in an overcurrent state, the driving signal DRIVE is in a low level, and the power switch tube 300 is immediately turned off.
When the signal processor 151 does not receive the overcurrent protection signal, the signal processor 151 outputs the received control signal to the driving circuit 152, and the driving circuit 152 generates the driving signal DRIVE according to the control signal to DRIVE the power switch tube 300 to be turned on or off. As shown in fig. 5-7, when the output terminal P1 of the overcurrent protection unit outputs a low level, the driving signal DRIVE is a PPG pulse driving signal, that is, when the power switch tube 300 is not in an overcurrent state, the driving signal DRIVE is the PPG pulse driving signal, and the power switch tube 300 is turned on or off under the driving of the PPG pulse.
Thus, the signal processor 151 processes the control signal, for example, the overcurrent protection signal, to control the driving circuit 152 to output a corresponding driving waveform to the power switch tube 300, so as to drive the power switch tube 300.
And, the voltage amplitude of the driving signal outputted by the driving circuit 152 can be adjusted according to the voltage control signal. As IN the example of fig. 5 (when the output terminal P1 of the over-current protection unit outputs a low level), when the PPG signal terminal 152 receives the PPG signal, the different voltage control signals IN2 correspond to the driving signals DRIVE with different voltage amplitudes, and when the voltage control signal IN2 is a high level, the voltage amplitude of the driving signal output by the driving circuit 152 to the power switch tube 300 is the first driving voltage V1; when the voltage control signal IN2 is at a low level, the voltage amplitude of the driving signal outputted from the driving circuit 152 to the power switch tube 300 is the second driving voltage V2. Wherein V1< V2, when the voltage amplitude of the driving signal is the first driving voltage V1, the power switch 300 operates in an amplification state, and when the voltage amplitude of the driving signal is the second driving voltage V2, the power switch 300 is in a saturated conduction state, i.e., a switching state.
In a specific example of the present invention, 7 V.ltoreq.V 1.ltoreq.12V, V2.gtoreq.15V.
It should be noted that, when the power switch tube 300 operates in the amplification state, the current value flowing through the power switch tube 300 is constant, and the current value is related to the voltage amplitude of the driving signal.
More specifically, according to an embodiment of the present invention, as shown in fig. 6, when the electromagnetic heating cooking system is in a start-up phase, the signal processor 151 adjusts the voltage amplitude of the driving signal to the first preset voltage V1, so that the power switch 300 operates in an amplifying state.
That is, at the starting moment of the electromagnetic heating cooking system, the current of the power switch tube 300 can be kept constant and the current value can be kept small by adjusting the voltage amplitude of the driving signal to the first preset voltage V1 corresponding to the amplified state. Specifically, as shown IN fig. 6, when the electromagnetic heating cooking system is IN the start-up phase T1, the signal processor 151 may adjust the voltage control signal IN2 to a high level, and when the voltage control signal IN2 is at the high level, the voltage amplitude of the driving signal output by the driving circuit 152 to the power switch 300 is the first driving voltage V1, and the power switch 300 operates IN the amplification state. Therefore, in the starting stage, the first preset voltage V1 is used as the voltage amplitude of the driving signal, so that the inrush current caused by hard switching of the power switch tube 300 can be reduced.
After the start-up phase is finished, the normal driving of the power switch tube 300 can be maintained by adjusting the voltage amplitude of the driving signal to the second preset voltage V2 corresponding to the amplified state. Specifically, as shown IN fig. 6, after the start-up period T1, the signal processor 151 may adjust the voltage control signal IN2 to a low level, and when the voltage control signal IN2 is at the low level, the voltage amplitude of the driving signal output by the driving circuit 152 to the power switch 300 is the second driving voltage V2, and the power switch 300 operates IN a saturation conducting state.
Alternatively, according to an embodiment of the present invention, as shown in fig. 7 and 8, when the electromagnetic heating cooking system is in the start-up phase, the signal processor 151 adjusts the voltage amplitude of the driving signal to a step voltage that is switched between the first preset voltage V1 and the second preset voltage V2, so that the power switch 300 is switched between the amplification state and the saturation conduction state accordingly.
That is, at the starting moment of the electromagnetic heating cooking system, the current of the power switch tube 300 can be kept constant and the current value can be kept small by adjusting the voltage amplitude of the driving signal to the first preset voltage V1 corresponding to the amplified state. Specifically, as shown IN fig. 7 (at this time, the output terminal P1 of the over-current protection unit outputs a low level), when the electromagnetic heating cooking system is IN the start-up stage T1, the signal processor 151 may adjust the voltage control signal IN2 to a high level, when the voltage control signal IN2 is a high level, the voltage amplitude of the driving signal output by the driving circuit 152 to the power switch tube 300 is a step voltage, and the amplified waveform of the step voltage is as shown IN fig. 8, that is, the voltage amplitude of the driving signal is first adjusted to a first preset voltage and kept for a first preset time T1, and after a first preset time T1, the voltage amplitude of the driving signal is then adjusted to a second preset voltage V2, where 2us ≦ T1 ≦ 5 us. Therefore, in the starting stage, the step voltage is used as the voltage amplitude of the driving signal, so that the impact current caused by hard switching of the power switch tube 300 can be reduced.
After the start-up phase is finished, the normal driving of the power switch tube 300 can be maintained by adjusting the voltage amplitude of the driving signal to the second preset voltage V2 corresponding to the amplified state. Specifically, as shown IN fig. 7, after the start-up period T1, the signal processor 151 may adjust the voltage control signal IN2 to a low level, and when the voltage control signal IN2 is at the low level, the voltage amplitude of the driving signal output by the driving circuit 152 to the power switch 300 is the second driving voltage V2, and the power switch 300 operates IN a saturation conducting state.
Therefore, the signal processor is integrated in the driving chip, and the power switching tube can be driven by adopting low voltage in the starting stage, so that the pulse current at the moment of starting the power switching tube is reduced.
In summary, according to the driving chip of the power switch tube in the electromagnetic heating cooking system provided by the embodiment of the invention, the current signal receiving end receives the current sampling signal generated by the current sampling unit according to the current flowing through the power switch tube, and the control signal receiving end receives the control signal output by the control chip, then the signal amplifying unit amplifies the current sampling signal, the overcurrent protection unit generates the overcurrent protection signal according to the amplified current sampling signal, the signal processing unit controls the power switch tube according to the control signal and through the driving unit, and the driving unit controls the power switch tube to be turned off when the overcurrent protection signal is received. Therefore, an overcurrent protection function is integrated in the driving chip, the power switch tube can be turned off in time when overcurrent faults occur, and the power switch tube is prevented from being burnt due to overlarge current. Moreover, the current sampling signal amplification function is integrated in the driving chip, so that the current sampling signal is amplified firstly and then transmitted, and compared with the mode of amplifying the current sampling signal firstly in transmission and then in transmission in the related technology, the stability is high, and the electromagnetic interference is not easy to generate.
The embodiment of the invention also provides an electromagnetic heating cooking system which comprises the driving chip of the power switch tube of the embodiment.
According to the electromagnetic heating cooking system provided by the embodiment of the invention, the performance of the electromagnetic heating cooking system can be improved through the driving chip of the power switch tube.
In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.
Claims (11)
1. A drive chip of a power switch tube in an electromagnetic heating cooking system is characterized by comprising:
the current signal receiving end is connected with the current sampling unit to receive a current sampling signal generated by the current sampling unit according to the current flowing through the power switch tube;
the signal amplification unit is connected with the current signal receiving end so as to amplify the current sampling signal and output the amplified current sampling signal;
the overcurrent protection unit is connected with the signal amplification unit so as to generate an overcurrent protection signal according to the amplified current sampling signal;
the control signal receiving end is connected with the control chip to receive the control signal output by the control chip;
the driving unit is respectively connected with the power switch tube, the control signal receiving end and the overcurrent protection unit, and is used for driving the power switch tube to be switched on or switched off according to the control signal and driving the power switch tube to be switched off when receiving the overcurrent protection signal;
the signal amplification unit is connected with the control chip so as to send the amplified current sampling signal to the control chip;
the driving unit includes:
the signal processor is respectively connected with the control signal receiving end and the overcurrent protection unit and is used for processing the control signal and the overcurrent protection signal to output a processed signal;
the driving circuit is connected with the signal processor and the power switch tube and drives the power switch tube according to the processed signal;
the control signal receiving end comprises a PPG signal end for receiving PPG signals and a voltage control end for receiving voltage control signals, wherein when the signal processor does not receive the over-current protection signals, the driving circuit outputs driving signals to the power switch tube according to the PPG signals so as to drive the power switch tube to be switched on or switched off, and adjusts the voltage amplitude of the driving signals according to the voltage control signals so as to enable the power switch tube to work in an amplification state or a saturation conduction state.
2. The driving chip of the power switch tube in the electromagnetic heating cooking system according to claim 1, wherein the signal amplifying unit comprises:
the positive input end of the operational amplifier is connected with the current signal receiving end;
one end of the first resistor is connected with the negative input end of the operational amplifier, and the other end of the first resistor is grounded;
and one end of the second resistor is connected with the negative input end of the operational amplifier, the other end of the second resistor is connected with the output end of the operational amplifier and is provided with a first node, and the first node is connected with the overcurrent protection unit.
3. The driving chip of the power switch tube in the electromagnetic heating cooking system according to claim 1, wherein the over-current protection unit comprises:
and the positive input end of the comparator is connected with the signal amplification unit, the negative input end of the comparator is connected with the reference voltage supply unit, and the output end of the comparator is connected with the driving unit.
4. The driving chip of the power switch tube in the electromagnetic heating cooking system according to claim 3, wherein the over-current protection unit further comprises:
one end of the third resistor is connected with a first preset power supply;
and one end of the first capacitor is connected with the other end of the third resistor, the other end of the first capacitor is grounded, a second node is arranged between the first capacitor and the third resistor, and the second node is connected with the output end of the comparator.
5. The driving chip of the power switch tube in the electromagnetic heating cooking system according to claim 3, wherein the reference voltage providing unit comprises a fourth resistor and a fifth resistor connected in series, one end of the fourth resistor and one end of the fifth resistor are connected to a first preset power supply, the other end of the fourth resistor and the other end of the fifth resistor are connected to ground, a third node is arranged between the fourth resistor and the fifth resistor, and the third node is connected to the negative input terminal of the comparator.
6. The electromagnetic heating cooking system according to any one of claims 1 to 5, wherein the power switch is an IGBT, a C pole of the IGBT is connected to the resonant heating circuit, an E pole of the IGBT is grounded, and a G pole of the IGBT is connected to the driving unit.
7. The driving chip of the power switch tube in the electromagnetic heating cooking system according to claim 6, wherein the current sampling unit comprises a sampling resistor, the sampling resistor is connected between the E pole of the IGBT and the ground, and a fourth node between the sampling resistor and the E pole of the IGBT is connected with the current signal receiving end.
8. The driving chip of the power switch tube in the electromagnetic heating cooking system according to claim 7, wherein the current sampling unit further includes a sixth resistor and a second capacitor, the sixth resistor is connected between the fourth node and the current signal receiving terminal, one end of the second capacitor is connected to the current signal receiving terminal, and the other end of the second capacitor is grounded.
9. The driving chip of the power switch tube in the electromagnetic heating cooking system according to claim 1, wherein when the electromagnetic heating cooking system is in a start-up phase, the signal processor adjusts the voltage amplitude of the driving signal to a first preset voltage, so that the power switch tube operates in an amplification state.
10. The driving chip of the power switch tube in the electromagnetic heating cooking system according to claim 1, wherein the signal processor adjusts the voltage amplitude of the driving signal to a step voltage switched between a first preset voltage and a second preset voltage when the electromagnetic heating cooking system is in a start-up phase, so that the power switch tube is switched between an amplification state and a saturation conduction state accordingly.
11. An electromagnetic heating cooking system, characterized in that, comprises a driving chip of the power switch tube according to any one of claims 1-10.
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| CN201610571898.7A CN107635299B (en) | 2016-07-18 | 2016-07-18 | Electromagnetic heating cooking system and driving chip of power switch tube thereof |
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| CN201610571898.7A CN107635299B (en) | 2016-07-18 | 2016-07-18 | Electromagnetic heating cooking system and driving chip of power switch tube thereof |
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| CN107635299B true CN107635299B (en) | 2021-06-18 |
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| CN110403443B (en) * | 2018-04-28 | 2023-01-24 | 佛山市顺德区美的电热电器制造有限公司 | Electromagnetic heating cooking utensil and IGBT (insulated Gate Bipolar transistor) drive control device and control method thereof |
| CN111786355A (en) * | 2020-06-23 | 2020-10-16 | 上海电器科学研究所（集团）有限公司 | Protection device and protection method for restraining short circuit of direct current bus support capacitor |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS617586A (en) * | 1984-06-20 | 1986-01-14 | 三洋電機株式会社 | Induction heater |
| CN201663720U (en) * | 2009-12-31 | 2010-12-01 | 深圳和而泰智能控制股份有限公司 | Induction cooker controller with IGBT protective circuit and induction cooler |
| CN201976277U (en) * | 2010-09-28 | 2011-09-14 | 佛山市顺德区瑞德电子实业有限公司 | Current sampling circuit of electromagnetic oven |
| CN203407031U (en) * | 2013-07-12 | 2014-01-22 | 美的集团股份有限公司 | Induction cooker and current sampling and current foldback circuit of induction cooker |
| CN105451385A (en) * | 2014-08-07 | 2016-03-30 | 佛山市顺德区美的电热电器制造有限公司 | Cooking device having function of over-current protection |
| CN205864246U (en) * | 2016-07-18 | 2017-01-04 | 佛山市顺德区美的电热电器制造有限公司 | Electromagnetic Heating cooking system and the driving chip of power switch pipe thereof |
-
2016
- 2016-07-18 CN CN201610571898.7A patent/CN107635299B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS617586A (en) * | 1984-06-20 | 1986-01-14 | 三洋電機株式会社 | Induction heater |
| CN201663720U (en) * | 2009-12-31 | 2010-12-01 | 深圳和而泰智能控制股份有限公司 | Induction cooker controller with IGBT protective circuit and induction cooler |
| CN201976277U (en) * | 2010-09-28 | 2011-09-14 | 佛山市顺德区瑞德电子实业有限公司 | Current sampling circuit of electromagnetic oven |
| CN203407031U (en) * | 2013-07-12 | 2014-01-22 | 美的集团股份有限公司 | Induction cooker and current sampling and current foldback circuit of induction cooker |
| CN105451385A (en) * | 2014-08-07 | 2016-03-30 | 佛山市顺德区美的电热电器制造有限公司 | Cooking device having function of over-current protection |
| CN205864246U (en) * | 2016-07-18 | 2017-01-04 | 佛山市顺德区美的电热电器制造有限公司 | Electromagnetic Heating cooking system and the driving chip of power switch pipe thereof |
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| CN107635299A (en) | 2018-01-26 |
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