CN203618153U - High-frequency induction heating power supply control circuit - Google Patents
High-frequency induction heating power supply control circuit Download PDFInfo
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- CN203618153U CN203618153U CN201320863343.1U CN201320863343U CN203618153U CN 203618153 U CN203618153 U CN 203618153U CN 201320863343 U CN201320863343 U CN 201320863343U CN 203618153 U CN203618153 U CN 203618153U
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Abstract
The utility model discloses a high-frequency induction heating power supply control circuit and relates to a high-frequency induction heating power supply control technology. The utility model aims to solve the problem of low power supply working efficiency caused by a capacitive work condition process which exists while phase lock of an existing high-frequency induction heating power control circuit. A load side current signal is divided into four paths, and the four paths of load side current signals are simultaneously input into the control circuit provided by the utility model. A positive half-wave rectification circuit and a negative half-wave rectification circuit are respectively perform half-wave rectification on the load side current signal, and then the processed signals are output; the output signals and the original load side current signals are processed through a first comparator circuit and a second comparator circuit, and then square-wave signals are output; and the square-wave signals are processed by a fist switch signal generator and a second switch signal generator, and then switch signals for controlling four field effect transistors in a MOSFET inversion circuit are output. According to the high-frequency induction heating power supply control circuit, a load can work in a weak-induction state all the time, and working efficiency of a high-frequency induction heating power supply is improved by 5%. The high-frequency induction heating power supply control circuit can be applied to the high-frequency induction heating power supply.
Description
Technical field
The utility model relates to high-frequency induction heating power control technology.
Background technology
Induction heating power has with it that efficiency of heating surface is high, speed is fast, controllability is good and automaticity advantages of higher, is widely used in industries such as melting, casting, bend pipe, forge hot, welding and surface heat processing.Control circuit in induction heating power must carry out power control to the system such as rectification circuit, inverter circuit main circuit part, makes to maintain the each parameter of system and do not depart from its set point under various disturbances.Domestic high-frequency induction heating power relatively lacks at present, and especially the research level of control technology is lower, thereby the research of control circuit is had to practical significance.Existing high-frequency induction heating power mainly relies on analog phase-locked look or digital phase-locked loop to realize control, there is capacitive operating state process in the shortcoming of this control circuit, causes power work efficiency low while being phase-locked, and control circuit complex structure, dynamic response is slow, and cost is high.
Utility model content
The purpose of this utility model is to have capacitive operating state process in order to solve existing high-frequency induction heating power control circuit when phase-locked, causes the inefficient problem of power work, and a kind of high efficiency high-frequency induction heating power control circuit is provided.
High-frequency induction heating power control circuit described in the utility model comprises positive half wave rectification circuit, the first comparator circuit, the first switching signal maker, negative half-wave rectifying circuit, the second comparator circuit, second switch signal generator, dead band control circuit and isolation drive unit;
Current signal input and the positive current signal input part of the second comparator circuit of the current signal input of positive half wave rectification circuit, the positive current signal input part of the first comparator circuit, negative half-wave rectifying circuit is connected the current signal output end of current detecting treatment circuit in high-frequency induction heating power simultaneously;
The current signal output end of positive half wave rectification circuit connects the negative current signal input part of the first comparator circuit, the square-wave signal output of the first comparator circuit connects signal input part of the first switching signal maker and a signal input part of second switch signal generator simultaneously, and the switching signal output of the first switching signal maker connects the first switching signal input of dead band control circuit;
The current signal output end of negative half-wave rectifying circuit connects the negative current signal input part of the second comparator circuit, the square-wave signal output of the second comparator circuit connects another signal input part of the first switching signal maker and another signal input part of second switch signal generator simultaneously, and the switching signal output of second switch signal generator connects the second switch signal input part of dead band control circuit;
Isolation drive unit comprises all identical isolated drive circuits of quadruplet independence and structure;
The first switching signal output of dead band control circuit connects the switch controlling signal input of first set isolated drive circuit in isolation drive unit, the second switch signal output part of dead band control circuit connects the switch controlling signal input of the second cover isolated drive circuit in isolation drive unit, the 3rd switching signal output of dead band control circuit connects the switch controlling signal input of the 3rd cover isolated drive circuit in isolation drive unit, the 4th switching signal output of dead band control circuit connects the switch controlling signal input of quadruplet isolated drive circuit in isolation drive unit,
In isolation drive unit, the switch controlling signal output of first set isolated drive circuit connects the first switch controlling signal input of inverter circuit in high-frequency induction heating power, in isolation drive unit, the switch controlling signal output of the second cover isolated drive circuit connects the second switch control signal input of inverter circuit in high-frequency induction heating power, in isolation drive unit, the switch controlling signal output of the 3rd cover isolated drive circuit connects the 3rd switch controlling signal input of inverter circuit in high-frequency induction heating power, in isolation drive unit, the switch controlling signal output of quadruplet isolated drive circuit connects the 4th switch controlling signal input of inverter circuit in high-frequency induction heating power.
High-frequency induction heating power control circuit described in the utility model, is divided into load-side current signal in positive half wave rectification circuit, the first comparator circuit, negative half-wave rectifying circuit and the second comparator circuit that four roads are input to control circuit simultaneously.In control circuit, positive half wave rectification circuit carries out this load-side current signal to export after positive half wave rectification, signal and the described load-side current signal of output are together input to the first comparator circuit, after the first comparator circuit is processed, export a square-wave signal, this square-wave signal is exported a switching signal after the first switching signal maker is processed; Meanwhile, after being born halfwave rectifier by negative half-wave rectifying circuit, exports described load-side current signal, signal and the described load-side current signal of output are together input to the second comparator circuit, after the second comparator circuit is processed, export a square-wave signal, this square-wave signal is exported a switching signal after second switch signal generator is processed.The control signal of the first switching signal maker and the output of second switch signal generator is input in MOSFET inverter circuit through dead band control circuit and isolation drive unit, is used for respectively controlling field effect transistor VT1 and the switch of field effect transistor VT4 and the switch of field effect transistor VT2 and field effect transistor VT3 in MOSFET inverter circuit.Load under the state that is similar to pure resistance and work even if high-frequency induction heating power control circuit described in the utility model can make the load moment be operated under weak perceptual state, make the operating efficiency of high-frequency induction heating power improve 5% compared with traditional analog phase-locked loop or digital phase-locked loop.In addition, present embodiment, compared with traditional control circuit, is being suitable under the prerequisite that supply frequency 1KHz～500KHz is constant, also has simple in structurely, with low cost, and stability is high, and dynamic responding speed can improve the advantage such as 10%.
Accompanying drawing explanation
Fig. 1 is the theory diagram of execution mode one medium-high frequency induction heating power;
Fig. 2 is the structured flowchart of the high-frequency induction heating power control circuit described in execution mode one;
Fig. 3 is the electrical block diagram of the positive half wave rectification circuit in execution mode two;
Fig. 4 is the first comparator circuit in execution mode four and the electrical block diagram of the second comparator circuit;
Fig. 5 is the electrical block diagram of the first switching signal maker in execution mode six;
Fig. 6 is the electrical block diagram of the second switch signal generator in execution mode seven;
Fig. 7 is the main circuit structure schematic diagram of execution mode one medium-high frequency induction heating power;
Fig. 8 is the electrical block diagram of dead band control circuit in execution mode one;
Fig. 9 is the electrical block diagram of the negative half-wave rectifying circuit in execution mode two.
Embodiment
Embodiment one: in conjunction with Fig. 1, Fig. 2, Fig. 7 and Fig. 8, present embodiment is described, the high-frequency induction heating power control circuit described in present embodiment comprises positive half wave rectification circuit 1, the first comparator circuit 2, the first switching signal maker 3, negative half-wave rectifying circuit 4, the second comparator circuit 5, second switch signal generator 6, dead band control circuit 7 and isolation drive unit 8;
Current signal input and the positive current signal input part of the second comparator circuit 5 of the current signal input of positive half wave rectification circuit 1, the positive current signal input part of the first comparator circuit 2, negative half-wave rectifying circuit 4 is connected the current signal output end of current detecting treatment circuit in high-frequency induction heating power simultaneously;
The current signal output end of positive half wave rectification circuit 1 connects the negative current signal input part of the first comparator circuit 2, the square-wave signal output of the first comparator circuit 2 connects signal input part of the first switching signal maker 3 and a signal input part of second switch signal generator 6 simultaneously, and the switching signal output of the first switching signal maker 3 connects the first switching signal input of dead band control circuit 7;
The current signal output end of negative half-wave rectifying circuit 4 connects the negative current signal input part of the second comparator circuit 5, the square-wave signal output of the second comparator circuit 5 connects another signal input part of the first switching signal maker 3 and another signal input part of second switch signal generator 6 simultaneously, and the switching signal output of second switch signal generator 6 connects the second switch signal input part of dead band control circuit 7;
Isolation drive unit 8 comprises all identical isolated drive circuits of quadruplet independence and structure;
The first switching signal output of dead band control circuit 7 connects the switch controlling signal input of first set isolated drive circuit in isolation drive unit 8, the second switch signal output part of dead band control circuit 7 connects the switch controlling signal input of the second cover isolated drive circuit in isolation drive unit 8, the 3rd switching signal output of dead band control circuit 7 connects the switch controlling signal input of the 3rd cover isolated drive circuit in isolation drive unit 8, the 4th switching signal output of dead band control circuit 7 connects the switch controlling signal input of quadruplet isolated drive circuit in isolation drive unit 8,
In isolation drive unit 8, the switch controlling signal output of first set isolated drive circuit connects the first switch controlling signal input of inverter circuit in high-frequency induction heating power, in isolation drive unit 8, the switch controlling signal output of the second cover isolated drive circuit connects the second switch control signal input of inverter circuit in high-frequency induction heating power, in isolation drive unit 8, the switch controlling signal output of the 3rd cover isolated drive circuit connects the 3rd switch controlling signal input of inverter circuit in high-frequency induction heating power, in isolation drive unit 8, the switch controlling signal output of quadruplet isolated drive circuit connects the 4th switch controlling signal input of inverter circuit in high-frequency induction heating power.
In high-frequency induction heating power, current detecting treatment circuit detects and processes the current signal of load-side, and load-side current signal is divided in positive half wave rectification circuit 1, the first comparator circuit 2, negative half-wave rectifying circuit 4 and the second comparator circuit 5 that four roads are input to control circuit simultaneously.In control circuit, positive half wave rectification circuit 1 carries out this load-side current signal to export after positive half wave rectification, signal and the described load-side current signal of output are together input to the first comparator circuit 2, after the first comparator circuit 2 is processed, export a square-wave signal, this square-wave signal is exported a switching signal after the first switching signal maker 3 is processed; Meanwhile, after being born halfwave rectifier by negative half-wave rectifying circuit 4, exports described load-side current signal, signal and the described load-side current signal of output are together input to the second comparator circuit 5, after the second comparator circuit 5 is processed, export a square-wave signal, this square-wave signal is exported a switching signal after second switch signal generator 6 is processed.The first switching signal maker 3 is divided into respectively two path control signal through dead band control circuit 7, Ji Gong tetra-tunnel control signals with the control signal that second switch signal generator 6 is exported.Gai Si road control signal is input in MOSFET inverter circuit behind isolation drive unit 8, is used for controlling four field effect transistor in MOSFET inverter circuit.The two paths of signals that the control signal that wherein the first switching signal maker 3 is exported is divided into is used for respectively controlling the switch of field effect transistor VT1 and field effect transistor VT4 in MOSFET inverter circuit, and the two paths of signals that the control signal that second switch signal generator 6 is exported is divided into is used for respectively controlling the switch of field effect transistor VT2 and field effect transistor VT3 in MOSFET inverter circuit.Load under the state that is similar to pure resistance and work even if the high-frequency induction heating power control circuit described in present embodiment can make the load moment be operated under weak perceptual state, make the operating efficiency of high-frequency induction heating power improve 5% compared with traditional analog phase-locked loop or digital phase-locked loop.In addition, present embodiment, compared with traditional control circuit, is being suitable under the prerequisite that supply frequency 1KHz～500KHz is constant, also has simple in structurely, with low cost, and stability is high, and dynamic responding speed can improve the advantage such as 10%.
Embodiment two: present embodiment is described in conjunction with Fig. 3 and Fig. 9, present embodiment is the further restriction to the high-frequency induction heating power control circuit described in execution mode one, in present embodiment, described positive half wave rectification circuit 1 comprises the first resistance R 0, adjustable resistance R1, the second resistance R 2, diode D and capacitor C, one end of described the first resistance R 0 is the current signal input of positive half wave rectification circuit 1, the other end of the first resistance R 0 connects the current input terminal of adjustable resistance R1, the current output terminal of adjustable resistance R1, the equal ground connection in one end of one end of capacitor C and the second resistance R 2, the other end of the second resistance R 2 connects the other end of capacitor C and the negative pole of diode D simultaneously, the positive pole of diode D connects the resistance adjustable side of adjustable resistance R1, the second resistance R 2, the common port of capacitor C and diode D is the current signal output end of positive half wave rectification circuit 1.
In present embodiment, positive half wave rectification circuit 1 is only that with the difference of negative half-wave rectifying circuit 4 polarity of diode D is contrary.Diode D is for carrying out halfwave rectifier to load-side current signal, wherein, diode D in positive half wave rectification circuit 1 is for load-side current signal is carried out to positive half wave rectification, and the diode D in negative half-wave rectifying circuit 4 is for bearing halfwave rectifier to load-side current signal.Capacitor C is for carrying out filtering to the signal after halfwave rectifier.Can change the phase difference of electric current and voltage in load-side current signal by regulating resistance R1.
Embodiment three: in conjunction with Fig. 3, present embodiment is described, present embodiment is the further restriction to the high-frequency induction heating power control circuit described in execution mode two, in present embodiment, described diode D adopts 1N4148 type diode to realize.
Embodiment four: present embodiment is described in conjunction with Fig. 4, present embodiment is the further restriction to the high-frequency induction heating power control circuit described in execution mode one, in present embodiment, the first described comparator circuit 2 has identical structure with the second comparator circuit 5, described the first comparator circuit 2 comprises the 3rd resistance R 4, the 4th resistance R 5 and comparator A, one end of described the 3rd resistance R 4 is the positive current signal input part of the first comparator circuit 2, the other end of the 3rd resistance R 4 connects the positive current signal input part of comparator A, one end of the 4th resistance R 5 is the negative current signal input part of the first comparator circuit 2, the other end of the 4th resistance R 5 connects the negative current signal input part of comparator A, the comparison signal output of comparator A is the square-wave signal output of the first comparator circuit 2.
Embodiment five: in conjunction with Fig. 4, present embodiment is described, present embodiment is the further restriction to the high-frequency induction heating power control circuit described in execution mode four, in present embodiment, described comparator A adopts LT1016CN8 type comparator to realize.
Embodiment six: present embodiment is described in conjunction with Fig. 5, present embodiment is the further restriction to the high-frequency induction heating power control circuit described in execution mode one, in present embodiment, the first described switching signal maker 3 comprises NOR gate circuit 31 and the first d type flip flop 32, two signal input parts of described NOR gate circuit 31 are two signal input parts of the first switching signal maker 3, the signal output part of NOR gate circuit 31 connects the clock signal input terminal of the first d type flip flop 32, the signal output part of the first d type flip flop 32 is the switching signal output of the first switching signal maker 3.
In present embodiment, the square-wave signal that the first comparator circuit 2 and the second comparator circuit 5 are exported enters the first switching signal maker 3, signal after NOR gate circuit 31 phase XORs is as the clock signal of the first d type flip flop 32, generates the switching signal of controlling field effect transistor VT1 and field effect transistor VT4 in MOSFET inverter circuit after the first d type flip flop 32 two divided-frequencies.
Embodiment seven: present embodiment is described in conjunction with Fig. 6, present embodiment is the further restriction to the high-frequency induction heating power control circuit described in execution mode one, in present embodiment, described second switch signal generator 6 comprises same OR circuit 61 and the second d type flip flop 62, two signal input parts of described same OR circuit 61 be second switch signal generator 6 two signal input parts, connect the clock signal input terminal of the second d type flip flop 62 with the signal output part of OR circuit 61, the signal output part of the second d type flip flop 62 is the switching signal output of second switch signal generator 6.
In present embodiment, the square-wave signal that the first comparator circuit 2 and the second comparator circuit 5 are exported enters second switch signal generator 6, through same OR circuit 61 identical or after signal as the clock signal of the second d type flip flop 62, after the second d type flip flop 62 two divided-frequencies, generate the switching signal of controlling field effect transistor VT2 and field effect transistor VT3 in MOSFET inverter circuit.
Claims (7)
1. high-frequency induction heating power control circuit, is characterized in that: it comprises positive half wave rectification circuit (1), the first comparator circuit (2), the first switching signal maker (3), negative half-wave rectifying circuit (4), the second comparator circuit (5), second switch signal generator (6), dead band control circuit (7) and isolation drive unit (8);
Current signal input and the positive current signal input part of the second comparator circuit (5) of the current signal input of positive half wave rectification circuit (1), the positive current signal input part of the first comparator circuit (2), negative half-wave rectifying circuit (4) is connected the current signal output end of current detecting treatment circuit in high-frequency induction heating power simultaneously;
The current signal output end of positive half wave rectification circuit (1) connects the negative current signal input part of the first comparator circuit (2), the square-wave signal output of the first comparator circuit (2) connects signal input part of the first switching signal maker (3) and a signal input part of second switch signal generator (6) simultaneously, and the switching signal output of the first switching signal maker (3) connects the first switching signal input of dead band control circuit (7);
The current signal output end of negative half-wave rectifying circuit (4) connects the negative current signal input part of the second comparator circuit (5), the square-wave signal output of the second comparator circuit (5) connects another signal input part of the first switching signal maker (3) and another signal input part of second switch signal generator (6) simultaneously, and the switching signal output of second switch signal generator (6) connects the second switch signal input part of dead band control circuit (7);
Isolation drive unit (8) comprises all identical isolated drive circuits of quadruplet independence and structure;
The first switching signal output of dead band control circuit (7) connects the switch controlling signal input of first set isolated drive circuit in isolation drive unit (8), the second switch signal output part of dead band control circuit (7) connects the switch controlling signal input of the second cover isolated drive circuit in isolation drive unit (8), the 3rd switching signal output of dead band control circuit (7) connects the switch controlling signal input of the 3rd cover isolated drive circuit in isolation drive unit (8), the 4th switching signal output of dead band control circuit (7) connects the switch controlling signal input of quadruplet isolated drive circuit in isolation drive unit (8),
In isolation drive unit (8), the switch controlling signal output of first set isolated drive circuit connects the first switch controlling signal input of inverter circuit in high-frequency induction heating power, in isolation drive unit (8), the switch controlling signal output of the second cover isolated drive circuit connects the second switch control signal input of inverter circuit in high-frequency induction heating power, in isolation drive unit (8), the switch controlling signal output of the 3rd cover isolated drive circuit connects the 3rd switch controlling signal input of inverter circuit in high-frequency induction heating power, in isolation drive unit (8), the switch controlling signal output of quadruplet isolated drive circuit connects the 4th switch controlling signal input of inverter circuit in high-frequency induction heating power.
2. high-frequency induction heating power control circuit according to claim 1, it is characterized in that: described positive half wave rectification circuit (1) comprises the first resistance (R0), adjustable resistance (R1), the second resistance (R2), diode (D) and electric capacity (C), one end of described the first resistance (R0) is the current signal input of positive half wave rectification circuit (1), the other end of the first resistance (R0) connects the current input terminal of adjustable resistance (R1), the current output terminal of adjustable resistance (R1), the equal ground connection in one end of one end of electric capacity (C) and the second resistance (R2), the other end of the second resistance (R2) connects the other end of electric capacity (C) and the negative pole of diode (D) simultaneously, the positive pole of diode (D) connects the resistance adjustable side of adjustable resistance (R1), the second resistance (R2), the common port of electric capacity (C) and diode (D) is the current signal output end of positive half wave rectification circuit (1).
3. high-frequency induction heating power control circuit according to claim 2, is characterized in that: described diode (D) adopts 1N4148 type diode to realize.
4. high-frequency induction heating power control circuit according to claim 1, it is characterized in that: described the first comparator circuit (2) has identical structure with the second comparator circuit (5), described the first comparator circuit (2) comprises the 3rd resistance (R4), the 4th resistance (R5) and comparator (A), one end of described the 3rd resistance (R4) is the positive current signal input part of the first comparator circuit (2), the other end of the 3rd resistance (R4) connects the positive current signal input part of comparator (A), one end of the 4th resistance (R5) is the negative current signal input part of the first comparator circuit (2), the other end of the 4th resistance (R5) connects the negative current signal input part of comparator (A), the comparison signal output of comparator (A) is the square-wave signal output of the first comparator circuit (2).
5. high-frequency induction heating power control circuit according to claim 4, is characterized in that: described comparator (A) adopts LT1016CN8 type comparator to realize.
6. high-frequency induction heating power control circuit according to claim 1, it is characterized in that: the first described switching signal maker (3) comprises NOR gate circuit (31) and the first d type flip flop (32), two signal input parts of described NOR gate circuit (31) are two signal input parts of the first switching signal maker (3), the signal output part of NOR gate circuit (31) connects the clock signal input terminal of the first d type flip flop (32), and the signal output part of the first d type flip flop (32) is the switching signal output of the first switching signal maker (3).
7. high-frequency induction heating power control circuit according to claim 1, it is characterized in that: described second switch signal generator (6) comprises same OR circuit (61) and the second d type flip flop (62), two signal input parts of described same OR circuit (61) be second switch signal generator (6) two signal input parts, the signal output part of same OR circuit (61) connects the clock signal input terminal of the second d type flip flop (62), and the signal output part of the second d type flip flop (62) is the switching signal output of second switch signal generator (6).
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| Application Number | Priority Date | Filing Date | Title |
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| CN201320863343.1U CN203618153U (en) | 2013-12-25 | 2013-12-25 | High-frequency induction heating power supply control circuit |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201320863343.1U CN203618153U (en) | 2013-12-25 | 2013-12-25 | High-frequency induction heating power supply control circuit |
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| CN203618153U true CN203618153U (en) | 2014-05-28 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106487244A (en) * | 2015-08-31 | 2017-03-08 | 董武文 | A kind of polarity rectifying and wave-filtering method |
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2013
- 2013-12-25 CN CN201320863343.1U patent/CN203618153U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106487244A (en) * | 2015-08-31 | 2017-03-08 | 董武文 | A kind of polarity rectifying and wave-filtering method |
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