CN110445408A - The control system of 10~300kHz broadband is adjustable Inverting digital power supply - Google Patents
The control system of 10~300kHz broadband is adjustable Inverting digital power supply Download PDFInfo
- Publication number
- CN110445408A CN110445408A CN201910779148.2A CN201910779148A CN110445408A CN 110445408 A CN110445408 A CN 110445408A CN 201910779148 A CN201910779148 A CN 201910779148A CN 110445408 A CN110445408 A CN 110445408A
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- Prior art keywords
- control system
- dsp
- real time
- time data
- circuit
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Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B6/00—Heating by electric, magnetic or electromagnetic fields
- H05B6/02—Induction heating
- H05B6/04—Sources of current
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B6/00—Heating by electric, magnetic or electromagnetic fields
- H05B6/02—Induction heating
- H05B6/06—Control, e.g. of temperature, of power
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/0003—Details of control, feedback or regulation circuits
- H02M1/0012—Control circuits using digital or numerical techniques
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- General Induction Heating (AREA)
Abstract
This application discloses the control systems of the adjustable Inverting digital power supply of one kind 10~300kHz broadband, are applied to induction heating equipment, comprising: FPGA, for controlling the input and output of operating circuit switching value；DSP carries out temperature control or energy hole to the operating circuit using pid control algorithm for acquiring the real time data of sensor, and according to the real time data.The system architecture that the application is combined by FPGA and DSP, had not only solved the deficiency of custom circuit, but also overcome the limited disadvantage of original programming device gate circuit number amount, and flexibly can accurately carry out temperature control, also improve power factor, more energy-efficient.
Description
Technical field
The present invention relates to induction heating field, in particular to the adjustable Inverting digital power supply of one kind 10~300kHz broadband
Control system.
Background technique
Currently, the induction heating power of domestic production is adopted mainly based on middle low frequency and superaudio in control hardware aspect
Control frequency range with analog circuit or monolithic processor controlled method, this kind of control method is relatively narrow, and control precision is not high, and
Once adjusting output frequency, then need to adjust compared with many places element, flexibility is poor.
Therefore, how to provide a kind of scheme of solution above-mentioned technical problem is that current those skilled in the art need to solve
Problem.
Summary of the invention
In view of this, the purpose of the present invention is to provide a kind of widebands for controlling precision height, flexible modulation, wide frequency range
The control system of rate is adjustable Inverting digital power supply.Its concrete scheme is as follows:
A kind of control system of the adjustable Inverting digital power supply of 10~300kHz broadband is applied to induction heating equipment, packet
It includes:
FPGA, for controlling the input and output of operating circuit switching value；
DSP, for acquiring the real time data of sensor, and according to the real time data, using pid control algorithm to described
Operating circuit carries out temperature control or energy hole.
Preferably, the DSP is specifically used for:
According to the real time data, using pid control algorithm, temperature is carried out to the operating circuit according to target temperature profile
Degree control, or energy hole is carried out to the operating circuit according to target power curve.
Preferably, the DSP is also used to:
The fault diagnosis and circuit protection of the operating circuit are carried out according to the real time data.
Preferably, the circuit protection includes:
Overcurrent protection, over-voltage or under-voltage protection, overheat protector, short-circuit protection, open-circuit-protection, input phase failure protection, induction
Device excessive low water level protection, current over-zero detection and phase-detection.
Preferably, the process of the fault diagnosis that the operating circuit is carried out according to the real time data, comprising:
The fault diagnosis of the operating circuit is carried out according to the real time data, and determines fault level.
Preferably, the control system further include:
The human-computer interaction interface being connect with the DSP；
It is connect with the DSP or the FPGA, the external interface of expansion module can be connect.
Preferably, the human-computer interaction interface specifically includes:
Tangible display screen and machine driving button.
Preferably, the external interface specifically includes:
I/O interface and/or RS485 interface and/or CAN interface.
Preferably, the control system further include:
Memory, for storing the operation log of the real time data and the DSP.
Preferably, the control system further include:
The host computer being connect with the DSP.
The invention discloses the control systems of the adjustable Inverting digital power supply of one kind 10~300kHz broadband, are applied to induction
Heating equipment, comprising: FPGA, for controlling the input and output of operating circuit switching value；DSP, for acquiring the reality of sensor
When data temperature control or energy control are carried out to the operating circuit using pid control algorithm and according to the real time data
System.The system architecture that the present invention is combined by FPGA and DSP, had not only solved the deficiency of custom circuit, but also overcome original compile
The shortcomings that journey device gate circuit limited amount, temperature control flexibly can be accurately carried out, power factor is also improved, more saves
It can be efficiently.
Detailed description of the invention
In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below
There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this
The embodiment of invention for those of ordinary skill in the art without creative efforts, can also basis
The attached drawing of offer obtains other attached drawings.
Fig. 1 is the knot of the control system of the adjustable Inverting digital power supply of one kind 10~300kHz broadband in the embodiment of the present invention
Structure distribution map；
Fig. 2 is a kind of control principle drawing of pid control algorithm in the embodiment of the present invention；
Fig. 3 is a kind of partial schematic diagram of target temperature profile in the embodiment of the present invention.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
The embodiment of the invention discloses the control system of the adjustable Inverting digital power supply of one kind 10~300kHz broadband, applications
It is shown in Figure 1 in induction heating equipment, comprising:
FPGA 1, for controlling the input and output of operating circuit switching value；
DSP 2, for acquiring the real time data of sensor, and according to the real time data, using pid control algorithm to institute
It states operating circuit and carries out temperature control or energy hole.
DSP (Digital Singnal Processor, digital signal processor) 2 in the present embodiment, optional model
TMS320F28335, the DSP have precision high, and at low cost, small power consumption, performance is high, and peripheral hardware integrated level is high, and data and program are deposited
The features such as reserves are big, and A/D conversion is more accurate quick, the high speed processing ability with 150MHz have 32 floating point processing units,
Support ADC (Analog to Digital in 6 (Direct Memory Access, direct memory access) channels DMA
Converter, analog-digital converter), (Multichannel Buffered Serial Port, multichannel buffer are serial by McBSP
Mouthful) and EMIF (External Memory Interface, external memory interface), there is the PWM (Pulse on up to 18 tunnels
Width Modulation, pulse width modulation) signal output, wherein having 6 tunnels is the distinctive high-precision PWM output of TI
(HRPWM), there are 12 16 channel ADC.In terms of data acquisition using FPGA (Field Programmable Gate Array,
Field programmable gate array) 1, it is in PAL (Programmable Array Logic, programmable logic array), GAL
(Generic Array Logic, Universal Array Logic), CPLD (Complex Programmable Logic Device, it is multiple
Miscellaneous programmable logic device) etc. the product that further develops on the basis of programming devices, as specific integrated circuit (ASIC)
One of field semi-custom circuit, FPGA 1 had not only solved the deficiency of custom circuit, but also overcame original programming device door
The limited disadvantage of circuit number.
Wherein, operating circuit specifically includes rectifying part, filtering part, Converting Unit, power output part and inductor,
Alternating current in power grid is converted to direct current by rectifying part, and direct current is converted to the alternating current of target output frequency by Converting Unit
After be sent to power output part, power output part by power transfer to inductor, make inductor to workpiece carry out induction plus
Heat.
Therefore, DSP 2 carry out data acquisition when, obtained real time data generally comprise operating circuit electric data and
The environmental data of surrounding, environmental data generally refer to workpiece temperature or cooling water temperature.Electric data includes operating circuit
Voltage value, current value etc., DSP 2 carries out operation monitoring and output power to the voltage value and current value of operating circuit, with this
Realize energy hole.
The induction heating equipment of the adjustable Inverting digital power supply of broadband, wideband here are mainly used in the present embodiment
Rate is adjustable to generally refer to the frequency range of 10~300kHz, and frequency range is wider, and the control system in the present embodiment can be real
It now flexibly accurately adjusts, does not need frequently to replace hardware circuit, also do not need frequently to adjust each device inside induction heating equipment
Relative position between part can satisfy a variety of induction heating demands.
It is understood that the system architecture that a FPGA+DSP is combined in the present embodiment, it can be to one or more works
Make circuit and carries out data acquisition, temperature control and energy hole.
Wherein, the DSP 2 is specifically used for: according to the real time data, using pid control algorithm, according to target temperature
Curve carries out temperature control to the operating circuit, or carries out energy hole to the operating circuit according to target power curve.
It is understood that the principle of pid control algorithm can accurately realize thermostatic control similar to Fig. 2 in DSP 2,
Make the error for controlling temperature can be with stability contorting in ± 1 degree Celsius range, so that the heating temperature of induction heating equipment can
Stablize in ± 5 degree Celsius ranges；Similar therewith, DSP 2 is able to carry out constant power output, namely ensure that effective in real time
Energy hole.In addition, DSP 2 can also carry out the adjusting of frequency automatic tracing using related algorithm, to remain higher electricity
Active power factor, usually between 92%~94%.
In general, target temperature profile includes three phases, first stage heating, second stage constant temperature, phase III
Cooling, Fig. 3 is a kind of example in target temperature profile the first two stage, in start temperature control DSP 2 according to target temperature song
Line carries out temperature control, and usual control form is that the Converting Unit into operating circuit exports relevant pwm signal.
It is understood that goal temperature curve can be by staff's self-setting, temperature height, time are long
Short and entire variation tendency can be carried out relevant parameter setting；In order to guarantee the working environment peace of induction heating equipment
Entirely, it needs first to do identification when target temperature profile is arranged, by inputting the methods of password, fingerprint recognition, Application on Voiceprint Recognition,
Determine the set interface that just can enter target temperature profile after staff's identity is errorless.
It is understood that the trend of target power curve, parameter setting are similar with target temperature profile, it is no longer superfluous herein
It states.
Further, the DSP 2 is also used to: according to the real time data carry out the operating circuit fault diagnosis and
Circuit protection.
Wherein, the circuit protection includes: overcurrent protection, over-voltage or under-voltage protection, overheat protector, short-circuit protection, open circuit
Protection, input phase failure protection, the detection of inductor excessive low water level protection, current over-zero and phase-detection.
It is understood that circuit protection mentioned here be directed to operating circuit, therefore be previously mentioned overcurrent, over-voltage, owe
Pressure, excess temperature, short circuit, phase shortage, water shortage are the failure that certain a part may occur in operating circuit, and specifically such as input overcurrent is protected
Shield, input phase failure protection, DC loop overvoltage protection, DC loop short-circuit protection, switching tube short-circuit protection, switching tube overcurrent
Protection, the protection of switching tube overheat protector, inversion output overcurrent, resonant tank short-circuit protection, resonant tank open-circuit-protection, inductor
The event of the components such as excessive low water level protection, cooling water over-voltage/under-voltage protection, cooling water overheat protector, converter module overheat protector, contactor
Barrier protection etc., wherein DC loop is often referred to circuit of the rectifying part for burning voltage, and switching tube is often referred to Converting Unit
The device of middle control circuit cutting or conducting, cooling water are induction heating equipment internal cooling system.And current over-zero detection and phase
Position detection, the purpose is to locking phases, prevent current break from burning out inverter module.
Further, the process of the fault diagnosis that the operating circuit is carried out according to the real time data, comprising:
The fault diagnosis of the operating circuit is carried out according to the real time data, and determines fault level.
It is understood that according to fault diagnosis as a result, relevant fault level can be determined.Different severity
Failure needs the processing of different stage, if fault level is more slight, can warn and remind staff, can also be same
When reduce output power, or adjustment target temperature profile reduces a possibility that fault level increases；If fault level is more serious,
It then needs to alert immediately, takes emergency stop measure, cutoff action circuit etc..
Further, the control system further include:
The human-computer interaction interface 3 being connect with the DSP 2；
It is connect with the DSP 2 or the FPGA 1, the external interface 4 of expansion module can be connect.
Wherein, the human-computer interaction interface 3 is specific can include:
Tangible display screen and machine driving button.
It is understood that human-computer interaction interface 3 can be used for real-time display input and output voltage, electric current, frequency, temperature,
The parameters such as power can carry out the parameter settings such as different target frequencies, target temperature, heating time, namely be mentioned above
Target temperature profile adjustment or power timesharing it is given etc..In view of the operation of actual working environment and old operative employee are practised
It is used, the part of above parameter setting can be equally realized by machine driving button, while also solving and wearing gloves or hand
The problem of when having when greasy dirt an inconvenient operation touch-screen.
Wherein, the external interface 4 specifically includes: I/O interface and/or RS485 interface and/or CAN interface.
It is understood that the external interface of control system is flexible in the present embodiment, for supporting multiple functions module
Extension, after the flexible suitable power supply of setting or communication interface, the input and output of control system can support up to 25 way switch
Analog signals such as amount, 12 road voltage and currents, while also supporting CAN bus, the Various types of data communication such as RS485, can with it is existing
PLC or industrial personal computer are communicated to realize automation control.
Further, the control system further include:
Memory 5, for storing the operation log of the real time data and the DSP 2.
It is understood that operation log includes acquiring the real time data being collected into, temperature controlled operation, failure before
Monitoring and troubleshooting movement etc..
Further, the control system further include:
The host computer 6 being connect with the DSP 2.
It is understood that host computer 6 can show the data of multiple induction heating equipments, and visual analyzing is made,
With more intuitively image embodies the working performance of the induction heating equipment.
The invention discloses the control systems of the adjustable Inverting digital power supply of one kind 10~300kHz broadband, are applied to induction
Heating equipment, comprising: FPGA, for controlling the input and output of operating circuit switching value；DSP, for acquiring the reality of sensor
When data temperature control or energy control are carried out to the operating circuit using pid control algorithm and according to the real time data
System.The system architecture that the present embodiment is combined by FPGA and DSP, had not only solved the deficiency of custom circuit, but overcome it is original can
The shortcomings that programming device gate circuit limited amount, flexibly can accurately carry out temperature control, also improve power factor, more
It is energy-efficient.
Finally, it is to be noted that, herein, relational terms such as first and second and the like be used merely to by
One entity or operation are distinguished with another entity or operation, without necessarily requiring or implying these entities or operation
Between there are any actual relationship or orders.Moreover, the terms "include", "comprise" or its any other variant meaning
Covering non-exclusive inclusion, so that the process, method, article or equipment for including a series of elements not only includes that
A little elements, but also including other elements that are not explicitly listed, or further include for this process, method, article or
The intrinsic element of equipment.In the absence of more restrictions, the element limited by sentence "including a ...", is not arranged
Except there is also other identical elements in the process, method, article or apparatus that includes the element.
Above to a kind of control system of the adjustable Inverting digital power supply of 10~300kHz broadband provided by the present invention into
It has gone and has been discussed in detail, used herein a specific example illustrates the principle and implementation of the invention, the above implementation
The explanation of example is merely used to help understand method and its core concept of the invention；Meanwhile for the general technology people of this field
Member, according to the thought of the present invention, there will be changes in the specific implementation manner and application range, in conclusion this explanation
Book content should not be construed as limiting the invention.
Claims (10)
1. the control system of one kind 10~300kHz broadband is adjustable Inverting digital power supply, which is characterized in that be applied to induction plus
Hot equipment, comprising:
FPGA, for controlling the input and output of operating circuit switching value；
DSP, for acquiring the real time data of sensor, and according to the real time data, using pid control algorithm to the work
Circuit carries out temperature control or energy hole.
2. control system according to claim 1, which is characterized in that the DSP is specifically used for:
According to the real time data, using pid control algorithm, temperature control is carried out to the operating circuit according to target temperature profile
System, or energy hole is carried out to the operating circuit according to target power curve.
3. control system according to claim 2, which is characterized in that the DSP is also used to:
The fault diagnosis and circuit protection of the operating circuit are carried out according to the real time data.
4. control system according to claim 3, which is characterized in that the circuit protection includes:
Overcurrent protection, over-voltage or under-voltage protection, overheat protector, short-circuit protection, open-circuit-protection, input phase failure protection, inductor lack
Water conservation, current over-zero detection and phase-detection.
5. control system according to claim 4, which is characterized in that described to carry out the work electricity according to the real time data
The process of the fault diagnosis on road, comprising:
The fault diagnosis of the operating circuit is carried out according to the real time data, and determines fault level.
6. according to claim 1 to any one of 5 control systems, which is characterized in that the control system further include:
The human-computer interaction interface being connect with the DSP；
It is connect with the DSP or the FPGA, the external interface of expansion module can be connect.
7. control system according to claim 6, which is characterized in that the human-computer interaction interface specifically includes:
Tangible display screen and machine driving button.
8. control system according to claim 6, which is characterized in that the external interface specifically includes:
I/O interface and/or RS485 interface and/or CAN interface.
9. control system according to claim 6, which is characterized in that further include:
Memory, for storing the operation log of the real time data and the DSP.
10. control system according to claim 9, which is characterized in that further include:
The host computer being connect with the DSP.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910779148.2A CN110445408A (en) | 2019-08-22 | 2019-08-22 | The control system of 10~300kHz broadband is adjustable Inverting digital power supply |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910779148.2A CN110445408A (en) | 2019-08-22 | 2019-08-22 | The control system of 10~300kHz broadband is adjustable Inverting digital power supply |
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| CN110445408A true CN110445408A (en) | 2019-11-12 |
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| CN109861519A (en) * | 2019-01-23 | 2019-06-07 | 广东美的制冷设备有限公司 | Power circuit and air conditioner |
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| CN102139823A (en) * | 2011-03-28 | 2011-08-03 | 江苏通用电梯有限公司 | Solar photovoltaic (PV) elevator control system with bidirectional power flow |
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Application publication date: 20191112 |