CN114302521B - Control method of induction heating device and induction heating device - Google Patents
Control method of induction heating device and induction heating device Download PDFInfo
- Publication number
- CN114302521B CN114302521B CN202111599930.XA CN202111599930A CN114302521B CN 114302521 B CN114302521 B CN 114302521B CN 202111599930 A CN202111599930 A CN 202111599930A CN 114302521 B CN114302521 B CN 114302521B
- Authority
- CN
- China
- Prior art keywords
- induction heating
- heating device
- operation parameter
- frequency
- signal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000010438 heat treatment Methods 0.000 title claims abstract description 121
- 230000006698 induction Effects 0.000 title claims abstract description 92
- 238000000034 method Methods 0.000 title claims abstract description 37
- 230000033228 biological regulation Effects 0.000 claims description 5
- 238000001914 filtration Methods 0.000 claims description 4
- 238000006243 chemical reaction Methods 0.000 description 8
- 230000001276 controlling effect Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 5
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 238000004378 air conditioning Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
Images
Landscapes
- General Induction Heating (AREA)
Abstract
The invention discloses a control method of an induction heating device and the induction heating device, the control method of the induction heating device comprises the following steps: calculating given operation parameters when the heating efficiency of the induction heating device reaches the target efficiency; collecting operation parameters related to the heating efficiency of the induction heating device, processing the operation parameters and enabling a processed result to be a feedback operation parameter; inputting the given operation parameter and the feedback operation parameter into a preset calculation model to output an adjusting signal; and adjusting the induction heating device through the adjusting signal to enable the feedback operation parameter to be close to or equal to the given operation parameter. The control method of the induction heating device provided by the invention realizes digitization of the adjusting process for maximizing the heating efficiency of the induction heating device, is convenient to control and adjust, and can improve the control precision.
Description
Technical Field
The invention relates to the field of heating equipment, in particular to a control method of an induction heating device and the induction heating device.
Background
With the development of power electronic technology, the induction heating power supply is more and more widely used for the fireless welding of an air conditioner copper pipe, the core for controlling the heating efficiency of the induction heating power supply lies in the adjustment of the resonance frequency of the heating coil, and the working efficiency of the induction heating power supply is the maximum when the resonance frequency of the heating coil is consistent with the switching frequency of an inverter circuit in the induction heating power supply.
In the prior art, the resonant frequency of the heating coil is generally adjusted by adopting a hardware chip to complete frequency tracking adjustment, the control scheme is not digitalized, and the control precision needs to be improved.
Disclosure of Invention
The invention provides a control method of an induction heating device and the induction heating device, aiming at solving the technical problem that the adjusting precision of a method for adjusting the resonance frequency of a heating coil in the induction heating device in the prior art is low.
The technical scheme adopted by the invention is as follows:
the invention provides a control method of an induction heating device, which comprises the following steps:
calculating given operation parameters when the heating efficiency of the induction heating device reaches the target efficiency;
collecting operation parameters related to the heating efficiency of the induction heating device, processing the operation parameters and enabling a processed result to be a feedback operation parameter;
inputting the given operation parameter and the feedback operation parameter into a preset calculation model to output an adjusting signal;
and adjusting the induction heating device through the adjusting signal to enable the output parameter of the induction heating device during operation to be close to or equal to the given operation parameter.
Further, the acquiring of the operation parameters related to the heating efficiency of the induction heating device, and the processing of the operation parameters and the setting of the processed result as the feedback operation parameters include: collecting an output current signal of the heating device; and converting the output current signal, wherein the processed result is the feedback operation parameter.
Further, the conversion process includes the steps of: phase shifting the adjustment signal produced by adjusting the output current signal; performing exclusive-or operation on the phase-shifted adjusting signal and a zero-crossing signal obtained from the output current signal; and converting the output value AD of the XOR operation and then filtering, wherein the result after filtering is the feedback operation parameter.
Further, the step of inputting the given operation parameter and the feedback operation parameter into a preset calculation model to output an adjustment signal includes the steps of: calculating a difference value between the given operation parameter and the feedback operation parameter, and performing proportional calculation and integral calculation on the difference value; accumulating the result of the proportional calculation and the calculation value of the integral calculation, and performing limit processing on the accumulated numerical value; and outputting the adjusting signal according to the numerical value after the limiting processing, wherein the frequency of the adjusting signal is the numerical value after the limiting processing.
Further, the limit processing includes: and when the accumulated numerical value is less than or equal to the maximum switching frequency of the inverter circuit in the induction heating device in normal operation and the accumulated numerical value is greater than or equal to the minimum switching frequency of the inverter circuit in the induction heating device in normal operation, the frequency of the output adjusting signal is the accumulated numerical value.
Further, the limit processing further includes: when the accumulated value is greater than the maximum switching frequency, the frequency of the output adjusting signal is the maximum switching frequency; and when the accumulated numerical value is smaller than the minimum switching frequency, the frequency of the output adjusting signal is the minimum switching frequency.
Further, the frequency corresponding to the given operation parameter is equal to the resonant frequency of the resonant circuit in the induction heating device when the efficiency of the induction heating device reaches the target efficiency.
An induction heating apparatus, a control method using the induction heating apparatus described above.
The induction heating device comprises a rectification circuit connected with a power grid, an inverter circuit connected with the rectification circuit, a heating coil connected with the inverter circuit and a controller for controlling the induction heating device.
In one embodiment, the induction heating device is an induction heating power supply.
Compared with the prior art, the control method of the induction heating device provided by the invention has the advantages that the given operation parameters when the efficiency of the induction heating device reaches the target efficiency and the feedback operation parameters acquired and processed in the current running state of the induction heating device are input into the preset calculation model for processing, the preset calculation model obtains the adjusting signal, the induction heating device adjusts the switching frequency of the induction heating device according to the adjusting signal, and the working efficiency of the induction heating device is improved.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.
FIG. 1 is a flow chart of a method for controlling an induction heating apparatus according to an embodiment of the present invention;
FIG. 2 is a diagram illustrating a result of the duty cycle of the XOR operation output waveform according to an embodiment of the present invention;
FIG. 3 is a diagram illustrating another example of the duty cycle of the XOR output waveform.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The induction heating device is widely applied to various fields, such as the use in the flameless welding of air-conditioning copper pipes, due to the particularity of the heating mode. The core of controlling the heating efficiency of the induction heating apparatus is the adjustment of the resonance frequency of the heating coil therein, and the operating efficiency of the induction heating apparatus is maximized when the resonance frequency of the heating coil coincides with the switching frequency of the inverter circuit in the induction heating apparatus.
In the prior art, the adjustment of the resonant frequency of the heating coil generally adopts a hardware chip to perform frequency tracking adjustment, the adjustment is fixed in the process, digitalization cannot be realized, and the control precision is also to be improved.
In order to solve various defects of the induction heating device, the invention provides a control method of the induction heating device, which comprises the following steps:
calculating a given operation parameter when the heating efficiency of the induction heating device reaches the target efficiency, wherein the given operation parameter is obtained by theoretical calculation under an ideal state according to the processing condition of the induction heating device;
collecting operation parameters related to the heating efficiency of the induction heating device, processing the operation parameters and taking the processed result as a feedback operation parameter;
inputting the given operation parameter and the feedback operation parameter into a preset calculation model to output an adjusting signal;
and adjusting the induction heating device through the adjusting signal to enable the feedback operation parameter to be close to or equal to the given operation parameter.
According to the control method of the induction heating device, the given operation parameters when the heating efficiency of the induction heating device reaches the target efficiency and the feedback operation parameters acquired and processed in the current running state of the induction heating device are input into the preset calculation model to be processed, the preset calculation model obtains the adjusting signal, the induction heating device adjusts the switching frequency of the induction heating device according to the adjusting signal, and the working efficiency of the induction heating device is improved.
The principles and construction of the present invention will be described in detail below with reference to the drawings and examples.
The induction heating apparatus in this embodiment is an induction heating power supply, which includes: the system comprises a rectification circuit connected with a power grid, an inverter circuit connected with the rectification circuit, an LC resonance circuit connected with the inverter circuit and a controller for controlling the induction heating device.
First, the given calculation parameter is a constant value in the entire control method, which corresponds to a regulation criterion. The resonant frequency can be calculated according to specific values of inductance and capacitance of the LC resonant circuit, the amplitude range of input voltage of the induction heating device in normal operation can be known according to the processing condition of the induction heating device, and a duty ratio X is selected. The method comprises the steps that a waveform can be obtained by integrating the resonant frequency, the voltage amplitude and the duty ratio X, a numerical value can be obtained after the waveform is subjected to AD conversion, the numerical value is set as a given operation parameter, the frequency reflected by the given operation parameter is equal to the resonant frequency of an LC resonant circuit, and when the switching frequency of an inverter circuit in the induction heating device also reaches the resonant frequency, the heating efficiency of the induction heating device can be maximized, which is the target efficiency of the induction heating device.
Further, as shown in fig. 1, the controller collects an output current signal of the inverter circuit, the collected output current signal is a waveform diagram of the output current, and a waveform diagram corresponding to the zero-crossing signal can be obtained from the waveform diagram of the output current signal. Meanwhile, only after the input end of the rectifying circuit receives the adjusting signal for driving the rectifying circuit to work, the rectifying circuit starts to work, and the inverter circuit can generate a corresponding output current signal, so that the output current signal of the inverter circuit acquired every time corresponds to an adjusting signal for driving the inverter circuit to generate. The feedback operation parameter is the result obtained after the zero-crossing signal and the adjusting signal generated by driving the zero-crossing signal are converted. Specifically, the conversion treatment is as follows: firstly, the adjusting signal is subjected to phase shifting (the phase shifting angle is equal to 180 degrees X), then the adjusting signal after phase shifting and a zero-crossing signal generated by the corresponding driving of the adjusting signal are subjected to exclusive-or operation processing, the output value of the exclusive-or operation is subjected to AD conversion and then filtered, and the filtered value is a feedback operation parameter. The XOR operation is performed on the regulation signal and the output current signal because both the regulation signal and the output current signal are oscillograms, and the feedback operation parameters and the given operation parameters input by the preset calculation model provided by the invention are specific numerical values in order to realize digitization of the whole control method and improve the control precision.
Further, the calculation process of the preset calculation model in the present invention is: subtracting the given operation parameter and the feedback operation parameter obtained according to the method to obtain a difference value, performing proportional calculation and integral calculation on the difference value, then accumulating the result of the proportional calculation and the result of the integral calculation, finally performing limit processing on the accumulated numerical value, and outputting an adjusting signal according to the numerical value after the limit processing, wherein the frequency of the adjusting signal is the numerical value after the limit processing. The limiting value processing comprises the steps that when the accumulated numerical value is smaller than or equal to the maximum switching frequency when an inverter circuit in the induction heating device normally operates and is larger than or equal to the minimum switching frequency when the inverter circuit in the induction heating device normally operates, the accumulated numerical value is the frequency of the adjusting signal; when the accumulated value is greater than the maximum switching frequency, the maximum switching frequency is the frequency of the adjusting signal; and when the accumulated value is smaller than the minimum switching frequency, the minimum switching frequency is the frequency of the regulating signal.
As can be seen from the above, the output result of the budget calculation model is the frequency of the adjustment signal, the adjustment signal is a waveform for driving the induction heating device, the voltage amplitude of the adjustment signal is determined according to the specific processing of the induction heating device as well as the given operation parameters, and the duty ratio of the adjustment signal is not limited herein.
From the above it is clear how the whole control method and the process parameters involved in the control method are available, and the method is explained in detail below with reference to fig. 2 and 3. In the present embodiment, it is first assumed that the duty ratio selected when calculating a given operation parameter is 50%, and the adjustment signal is a square wave signal having a duty ratio of 50%. An output current signal which is a sine wave is collected at a certain moment in the operation process, a zero-crossing signal which is a square wave is obtained from the output current signal, the corresponding adjusting signal is shifted by 90 degrees (180 degrees by 50 percent), then the adjusted signal after phase shifting and the zero-crossing signal are subjected to exclusive-or operation, and if the duty ratio of a graph after exclusive-or operation is 50 percent, the switching frequency of the inverter circuit at the moment is equal to the resonance frequency (shown in figure 2). And performing AD conversion on the result of the XOR operation, wherein the frequency corresponding to the value obtained after the conversion is equal to the frequency corresponding to the given parameter, the difference calculated by the budget calculation model is zero at the moment, and the adjustment of the switching frequency of the heating device is in place. If the duty ratio of the pattern after the exclusive or operation is not 50%, it indicates that the switching frequency of the inverter circuit is not equal to the resonant frequency (shown in fig. 3). And performing AD conversion on the result of the XOR operation, wherein the frequency corresponding to the value obtained after the conversion is not equal to the frequency corresponding to the given parameter, the difference calculated by the budget calculation model is not zero at the moment, the budget calculation model can obtain an output value according to the difference, the output value is the frequency value of the next adjusting signal, and the heating device adjusts the switching frequency according to the adjusting signal. The entire heating device repeats the above process until the switching frequency is adjusted to coincide with the resonance frequency.
The present invention also proposes an induction heating apparatus using the control method described above.
The control method of the induction heating device provided by the invention realizes the digital realization method that the switching frequency of the inverter circuit is consistent with the resonance frequency of the heating coil, is convenient to control and adjust, and can improve the control precision.
The above description is intended to be illustrative of the preferred embodiment of the present invention and should not be taken as limiting the invention, but rather, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.
Claims (8)
1. A control method of an induction heating apparatus, characterized by comprising the steps of: calculating given operation parameters when the heating efficiency of the induction heating device reaches the target efficiency; collecting an output current signal of the heating device, and shifting the phase of an adjusting signal generated by adjusting the output current signal; performing exclusive-or operation on the phase-shifted adjusting signal and a zero-crossing signal obtained from the output current signal; converting the output value AD of the XOR operation and then filtering, and enabling the result after filtering processing to be a feedback operation parameter; inputting the given operation parameter and the feedback operation parameter into a preset calculation model to output another regulation signal; and adjusting the induction heating device through the adjusting signal output by the preset calculation model to enable the feedback operation parameter to be close to or equal to a given operation parameter.
2. The control method of an induction heating apparatus as set forth in claim 1, wherein said inputting said given operation parameter and said feedback operation parameter into a preset calculation model to output another regulation signal comprises the steps of: calculating a difference value between the given operation parameter and the feedback operation parameter, and performing proportional calculation and integral calculation on the difference value; accumulating the result of the proportional calculation and the calculation value of the integral calculation, and performing limit processing on the accumulated numerical value; and outputting the adjusting signal according to the numerical value after the limit value processing, wherein the frequency of the adjusting signal is the numerical value after the limit value processing.
3. The control method of an induction heating apparatus according to claim 2, characterized in that said limit processing includes: and when the accumulated numerical value is less than or equal to the maximum switching frequency of the inverter circuit in the induction heating device in normal operation and the accumulated numerical value is greater than or equal to the minimum switching frequency of the inverter circuit in the induction heating device in normal operation, the frequency of the output adjusting signal is the accumulated numerical value.
4. The control method of an induction heating apparatus according to claim 3, wherein said limit processing further comprises: when the accumulated value is greater than the maximum switching frequency, the frequency of the output adjusting signal is the maximum switching frequency; and when the accumulated value is smaller than the minimum switching frequency, the frequency of the output adjusting signal is the minimum switching frequency.
5. The control method of an induction heating apparatus according to claim 1, wherein the frequency corresponding to said given operation parameter is equal to a resonance frequency of a resonance circuit in said induction heating apparatus at which an efficiency of said induction heating apparatus reaches a target efficiency.
6. An induction heating apparatus, characterized by using the control method of an induction heating apparatus according to any one of claims 1 to 5.
7. The induction heating apparatus as set forth in claim 6, comprising a rectification circuit connected to a power grid, an inverter circuit connected to said rectification circuit, a resonance circuit connected to said inverter circuit, and a controller controlling said induction heating apparatus.
8. The induction heating unit of claim 7, wherein said induction heating unit is an induction heating power supply.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111599930.XA CN114302521B (en) | 2021-12-24 | 2021-12-24 | Control method of induction heating device and induction heating device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111599930.XA CN114302521B (en) | 2021-12-24 | 2021-12-24 | Control method of induction heating device and induction heating device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114302521A CN114302521A (en) | 2022-04-08 |
| CN114302521B true CN114302521B (en) | 2022-11-25 |
Family
ID=80969280
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111599930.XA Active CN114302521B (en) | 2021-12-24 | 2021-12-24 | Control method of induction heating device and induction heating device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114302521B (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102403923A (en) * | 2011-09-01 | 2012-04-04 | 阳春丽 | PWM (pulse width modulation) phase-shifting control method |
| CN110493907A (en) * | 2019-09-18 | 2019-11-22 | 安徽工程大学 | A kind of digitlization induction heating power and its control method |
-
2021
- 2021-12-24 CN CN202111599930.XA patent/CN114302521B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102403923A (en) * | 2011-09-01 | 2012-04-04 | 阳春丽 | PWM (pulse width modulation) phase-shifting control method |
| CN110493907A (en) * | 2019-09-18 | 2019-11-22 | 安徽工程大学 | A kind of digitlization induction heating power and its control method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114302521A (en) | 2022-04-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101814825B (en) | Linear-regulated PFC (Power Factor Correction) control circuit and control method | |
| CN108900093B (en) | Single-phase PFC circuit power frequency ripple eliminating method, PFC topology system and charging pile system | |
| CN108809073A (en) | Control method, control system and the air conditioner of APFC circuit voltages | |
| CN103280808A (en) | Variable ring width hysteresis current control method based on timer | |
| CN106340939A (en) | Contactless power transmission device and power transfer system | |
| CN112787496B (en) | Variable frequency controller, control method thereof and variable frequency electric appliance | |
| CN104883042A (en) | Method and device for processing output voltage ripple of charger | |
| CN114302521B (en) | Control method of induction heating device and induction heating device | |
| CN104113199A (en) | Active PFC circuit and control method thereof | |
| CN109067194B (en) | Control method and control circuit for frequency converter, medium and frequency conversion air conditioner | |
| JP4572595B2 (en) | CONVERTER CONTROL METHOD, CONVERTER CONTROL DEVICE, AIR CONDITIONER, ITS CONTROL METHOD AND CONTROL DEVICE | |
| CN112600272B (en) | Constant-current constant-voltage control method and system based on wireless charging system | |
| CN1799187B (en) | Inverter power source control circuit for high-frequency heater | |
| KR20140102183A (en) | Rectifier device and method for controlling same | |
| CN203301359U (en) | Active PFC circuit | |
| CN112968597B (en) | Single-period control method of power factor correction circuit in continuous mode | |
| JP2012010558A (en) | System interconnection power converter and method for controlling system interconnection power converter | |
| CN111641333B (en) | Multi-carrier period PFC control method | |
| CN113036939B (en) | Non-contact electromagnetic conversion power supply device and power supply method | |
| CN114679047A (en) | Control method and control device of power factor correction circuit and air conditioner | |
| CN110995045A (en) | Inverter system with low-pass filter and improved control method thereof | |
| Park et al. | PFC dual boost converter based on input voltage estimation for DC inverter air conditioner | |
| CN104702132B (en) | A kind of control method and device of switching tube | |
| CN113078810B (en) | Intelligent power factor correction method for medical switching power supply | |
| CN114337307B (en) | Control system and control method for single-stage resonant conversion device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |