CN110446290B - Quasi-resonance control method for induction heating - Google Patents
Quasi-resonance control method for induction heating Download PDFInfo
- Publication number
- CN110446290B CN110446290B CN201910759576.9A CN201910759576A CN110446290B CN 110446290 B CN110446290 B CN 110446290B CN 201910759576 A CN201910759576 A CN 201910759576A CN 110446290 B CN110446290 B CN 110446290B
- Authority
- CN
- China
- Prior art keywords
- frequency
- reactive power
- fundamental wave
- induction heating
- moment
- 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
Images
Classifications
-
- 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
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- General Induction Heating (AREA)
Abstract
The invention provides a quasi-resonance control method for induction heating, which comprises the following steps: firstly, detecting the fundamental wave reactive power and frequency at the current moment; secondly, comparing the fundamental wave reactive power with a constant greater than 0, and calculating the forward difference of the fundamental wave reactive power at the current moment; obtaining a frequency step by utilizing a forward difference value of fundamental wave reactive power; and finally, adjusting the system from high frequency to low frequency according to the frequency step length, and outputting the system to a control unit to regulate and control the main circuit so that the main circuit is in a quasi-resonance state. When the fundamental wave reactive power is close to 0, the step length of the frequency is adjusted by adopting a step length variable frequency method, overshoot or oscillation is avoided, the tracking speed of the induction heating system is improved, and the fundamental wave reactive power is set to be a constant larger than 0 during control, so that the induction heating system is in a weak-induction quasi-resonance state, and the problem of a weak-capacitive state caused by disturbance is avoided.
Description
Technical Field
The invention relates to the technical field of manufacturing of induction heating equipment, in particular to a quasi-resonance control method for induction heating.
Background
Compared with other heating modes, the induction heating has the advantages of high heating efficiency, high speed, good controllability, easy realization and the like, thereby being widely applied to the industrial fields of metallurgy, machinery, electronics and the like. The traditional induction heating mode of series resonance heating has the advantages of small power adjustment range, low tracking precision of resonance frequency and difficult coordination of efficiency. In order to improve the utilization rate of the power supply of the induction heating system, the power supply is usually operated in a resonance state, but in the heating process, the performance parameters of the heating material are changed due to the change of temperature, so that the inherent resonance frequency of the system is changed. If the output frequency of the power supply cannot be adjusted in time, the system can work in a non-resonant state. Frequency tracking techniques are required to ensure that the induction heating system is always operating at resonance.
When the circuit resonates, the circuit has the following characteristics: 1) the circuit is resistive, i.e. the current and the voltage are in the same phase; 2) the current in the circuit is maximum; 3) the maximum active power output and the maximum reactive power output simultaneously are 0; 4) the voltages on the capacitor and inductor are opposite in phase, equal in magnitude and possibly greater than the supply voltage, etc. According to the characteristic of the resonance circuit, the method for judging whether the circuit is in resonance comprises the following steps: judging by monitoring whether the current and voltage phases are in the same phase; detecting whether the voltages on the capacitor and the inductor are equal to each other or not to judge; whether the output power is maximum or not and whether the output no-power is 0 or not are judged. Each of these judgment methods has merits and demerits. The method comprises the steps of monitoring whether the phase of current and voltage is in the same phase or not, detecting the current of a resonant circuit, generating a PWM (pulse width modulation) driving signal with the same frequency as the current of the resonant circuit after phase compensation and zero-crossing comparison, and enabling the working frequency of an inverter to be equal to or slightly higher than the resonant frequency of the inverter. The method for detecting whether the voltages on the capacitor and the inductor are equal or not is adopted, the voltage on the inductor cannot be directly measured, and the method is rarely used in practice; the frequency tracking method is adjusted by using the maximum output power method, and disturbance near a maximum power point is easy to slide to a weak capacitive state in the adjusting process, so that large peak current is caused when a switching device is switched on in a current conversion mode, and bridge arm direct connection is caused by reverse recovery of a freewheeling diode.
Disclosure of Invention
The invention provides a quasi-resonance control method for induction heating, wherein the maximum power point of induction heating changes along with the change of parameters, and the problem that the system is easy to slide to a weak capacitive state due to disturbance when the system is in a resonance state by adopting methods such as disturbance observation and the like is solved. Aiming at the defect that the induction heating is in a resonance method by the traditional maximum power tracking method, the induction heating circuit system is in a weak-inductance quasi-resonance state by detecting reactive power and controlling according to the condition that the active power is maximum (not a fixed value) and the reactive power is 0 (a fixed value) during resonance. The reactive power is set to a value slightly larger than 0, so that the problem of weak capacitive state caused by disturbance when the reactive power is 0 is avoided. Meanwhile, the tracking speed of the induction heating circuit system can be improved by adopting variable step frequency tracking monitoring.
The technical scheme of the invention is realized as follows:
a quasi-resonance control method for induction heating comprises the following steps:
s1, collecting the voltage u (k) and the current i (k) output by the main circuit at the moment k by using a detection circuit, calculating the fundamental wave reactive power Q (k) at the moment k, and recording the frequency f (k) at the moment k;
s2, judging whether the fundamental wave reactive power Q (k) at the moment k is equal to a threshold h, if so, judging whether the frequency f (k +1) at the moment k +1 is equal to the frequency f (k) at the moment k, executing a step S7, otherwise, executing a step S3, wherein the threshold h is a constant greater than zero;
s3, calculating a difference value delta Q of the fundamental wave reactive power at the moment k and the moment k-1, and calculating a frequency step length delta f according to the difference value delta Q of the fundamental wave reactive power;
s4, judging whether the fundamental wave reactive power Q (k) at the moment k is larger than a threshold value h, if so, executing a step S5, otherwise, executing a step S6;
s5, adding the frequency f (k) in step S1 to the frequency step Δ f in step S3 to obtain the frequency f (k +1) at the time of k +1, and executing step S7;
s6, subtracting the frequency step Δ f from step 3 from the frequency f (k) in step S1 to obtain the frequency f (k +1) at the time of k +1, and executing step S7;
and S7, outputting the frequency f (k +1) at the moment of k +1 to the control unit to regulate and control the main circuit.
The method for calculating the fundamental wave reactive power q (k) at the time k in step S1 includes:
s11, collecting voltage u of main circuit at moment kα(k) And current iα(k) Voltage uα(k) And current iα(k) Respectively phase-shifted by 90 degrees to obtain a voltage uβ(k) And current iβ(k)；
S12, converting the voltage u on the coordinate system alpha betaα(k) And voltage uβ(k) Obtaining a voltage u (k) on a coordinate system dq through coordinate transformation;
s13, converting the current i in the coordinate system alpha betaα(k) And current iβ(k) Obtaining current i (k) on a coordinate system dq through coordinate transformation;
s14, calculating power W (k) on a coordinate system dq according to the voltage u (k) in the step S12 and the current i (k) in the step S13;
and S15, dividing the power W (k) obtained in the step S14 into active power p (k) and reactive power q (k), and performing low-pass filtering on the reactive power q (k) to obtain fundamental wave reactive power Q (k).
The power w (k) in step S14 is: w (k) u (k) i (k), w (k) p (k) + q (k).
The frequency step Δ f in step S3 is a variation value, and the magnitude of the frequency step Δ f is related to the magnitude of the difference Δ Q of the fundamental wave reactive power.
The frequency step length delta f is calculated by adopting a piecewise function, fuzzy control or a neural network.
A control system of a quasi-resonance control method for induction heating comprises a control unit, a detection filter circuit, a photoelectric isolation and drive circuit and a main circuit; the control unit is connected with the detection filter circuit, the control unit is connected with the photoelectric isolation and drive circuit, the photoelectric isolation and drive circuit is connected with the main circuit, and the main circuit is connected with the detection filter circuit.
The beneficial effect that this technical scheme can produce: the method adopts a step length changing method when the frequency is changed, the smaller the step length of the frequency is adjusted when the fundamental wave reactive power is close to 0, the overshoot is avoided, the induction heating circuit system slides to the capacitive property, and the frequency tracking speed of the induction heating circuit system is increased; during control, the fundamental wave reactive power Q is h (h is greater than 0) instead of Q being 0, so that the induction heating circuit system is ensured to work in a weak induction state.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a flow chart of the present invention.
Fig. 2 is a fundamental reactive power detection schematic diagram of the present invention.
Fig. 3 is a schematic structural diagram of a quasi-resonant control system according to an embodiment of the present invention.
Fig. 4 is an equivalent schematic diagram of the induction heating circuit system of the present invention.
Fig. 5 is a phasor diagram of the capacitance, inductance and resistance of fig. 4.
Fig. 6 is a graph of impedance versus frequency of fig. 4.
Fig. 7 is a graph of the output power versus frequency of fig. 4.
Fig. 8 is a schematic diagram of a single-phase full-bridge structure according to an embodiment of the present invention.
Fig. 9 is a single term full bridge waveform diagram of fig. 8.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive effort based on the embodiments of the present invention, are within the scope of the present invention.
The embodiment 1 of the invention provides a quasi-resonance control method for induction heating, an equivalent schematic diagram of an induction heating circuit system is shown in fig. 4, the equivalent schematic diagram comprises a power supply, a resistor R, an inductor L and a capacitor C, the resistor R, the inductor L and the capacitor C are connected in series, and the voltage at two ends of the power supply is
The voltages on the resistor R, the inductor L and the capacitor C are respectively
And
the phasor diagram of the resistor R, the inductor L and the capacitor C is shown in fig. 5. The value of equivalent inductance of the induction heating circuit system is different due to different load temperatures, and the resonant frequency of the induction heating circuit system is changed accordingly. By inductionThe resonant frequency f can be known by the equivalent principle of the heating circuit system0Comprises the following steps:
the output power versus frequency curve for an induction heating system is shown in fig. 7. The closer the system frequency is to the resonance point frequency, the larger the output power is, and the real-time power tracking can be carried out according to the characteristic. In the traditional method, frequency tracking is realized by a phase-locked loop or zero-crossing detection technology and a hardware circuit thereof, so that a system reaches a quasi-resonance state to output the maximum power, and the method is seriously dependent on the performance of the zero-crossing detection and phase-locked loop technology. And the negative influence caused by using a hardware circuit can be avoided by directly utilizing the power tracking through the power characteristic curve, and the output power is directly tracked to be maintained at the secondary maximum power. The design process is simplified, the hardware circuit is simplified, and the system structure is simplified.
The series resonant circuit is characterized in that: the current in the circuit is maximum; the output power is maximum or no power is minimum; the voltages on the capacitor and inductor are equal and possibly greater than the supply voltage; the circuit exhibits pure resistance, etc. The method for judging whether the circuit is in resonance according to the characteristics of the series resonance circuit mainly comprises the following steps: (1) whether the current and voltage are in phase; (2) whether the current in the circuit is maximum; (3) whether the output power is maximum; (4) whether the voltages on the capacitor and the inductor are equal; (5) whether the output reactive power is 0, etc. The method has certain difficulty in accurately judging whether the actual series resonance heating circuit is in the resonance state or not, and the advantages and the disadvantages of the method are different.
As shown in fig. 6, when f ═ f0When the load equivalent impedance is minimum, namely R, the power output power is maximum; when f is>f0When the frequency of the power supply is increased, the equivalent impedance of the load is inductive, and the output power of the power supply is reduced along with the increase of the frequency; when f is<f0And the equivalent impedance of the load is capacitive, and the output power of the power supply is reduced along with the reduction of the frequency. From the above analysis, it can be seen that the power supply output power is maximum or the reactive power is 0 only at the time of resonance. In practiceIn the control engineering, in order to avoid the phenomenon that a working point slides to a capacitive state, so that a larger peak current is caused when a switching device is switched on in a current conversion mode and a bridge arm is directly connected due to the reverse recovery of a fly-wheel diode, the working frequency of a switch of the inverter is controlled to be slightly greater than the inherent resonant frequency f of a load0So as to ensure that the load loop of the induction heating circuit system works in a weak induction resonance state, namely a quasi-resonance state.
The quasi-resonance control method for induction heating comprises the following steps: the inductance of the load element of the induction heating circuit system changes due to the increase or decrease of the load temperature, so that the oscillation frequency also changes along with the change of the load temperature. If the induction heating circuit system is always in a resonance state, the frequency output by the inverter is also changed. The invention adopts a control strategy of controlling the output reactive power to be close to 0 but slightly larger than 0, and controls the output frequency of the DC/AC inverter system to be adjusted from high to low, so that the induction heating circuit system works in a weak-induction quasi-resonance state.
The medium-high frequency induction heating circuit system is generally controlled by square waves, a single-phase voltage type full-bridge inverter circuit schematic diagram is shown in fig. 8, a single-phase full-bridge circuit comprises four switching tubes which can be regarded as two half-bridge circuits, namely VT1And VT4Is a half-bridge circuit, VT2And VT3Is a half bridge circuit. When the square wave control is adopted, the paired switching tubes are simultaneously switched on and off, the difference between the on and off is 180 degrees, and the inductive voltage uoThe waveform of (2) is shown in fig. 9.
The voltage u of the inductoroExpanding into a Fourier series, comprising:
as can be seen from the formula (2), the output waveform contains low harmonics such as 3, 5, and 7.
When the temperature of the heating workpiece changes, the equivalent inductance of the heating workpiece also changes, so that the resonant frequency of the circuit changes. For the square wave control adopted in fig. 9, because the low-order harmonic content is large, the conventional current zero crossing point detection frequency tracking method is not accurate enough, and the power generated by the low-order harmonic is not considered. And the method for enabling the circuit to be in the accurate resonance state by adopting the frequency tracking method that the reactive power tends to be 0 is more accurate.
The fundamental principle of the frequency tracking method that the fundamental wave reactive power tends to be 0 is as follows: first, the fundamental wave reactive power Q during the adjustment of the frequency from high to low during induction heating is detected, and if the fundamental wave reactive power Q >0, the frequency is decreased, whereas if Q is 0, the frequency is increased, and the frequency is maintained. Such control switches the induction heating system circuitry between weak capacitive, resistive and weak inductive properties. The analysis of the induction heating circuit system shows that the working point slides to a capacitive resonance state, so that large peak current is caused when the commutation of the switching device is switched on, and bridge arm direct connection is caused by the reverse recovery of the freewheeling diode. Therefore, in order to avoid this, the frequency tracking method with reactive power of 0 needs to be improved.
As shown in fig. 1, a quasi-resonance control method for induction heating includes the following steps:
s1, collecting the voltage u (k) and the current i (k) output by the main circuit at the moment k by using the detection circuit, calculating the fundamental wave reactive power Q (k) at the moment k, and recording the frequency f (k) at the moment k.
As shown in fig. 2, the method for calculating the fundamental reactive power q (k) at time k in step S1 includes:
s11, collecting voltage u of main circuit at moment kα(k) And current iα(k) Voltage uα(k) And current iα(k) Respectively phase-shifted by 90 degrees to obtain a voltage uβ(k) And current iβ(k)。
S12, converting the voltage u on the coordinate system alpha betaα(k) And voltage uβ(k) The voltage u (k) on the coordinate system dq is obtained by coordinate transformation.
S13, converting the current i in the coordinate system alpha betaα(k) And current iβ(k) The current i (k) in the coordinate system dq is obtained by coordinate transformation.
S14, calculating power W (k) on a coordinate system dq according to the voltage u (k) in the step S12 and the current i (k) in the step S13; the power W (k) is: w (k) u (k) i (k), w (k) p (k) + q (k).
And S15, dividing the power W (k) obtained in the step S14 into active power p (k) and reactive power q (k), and passing the reactive power through a low-pass filter LPF to obtain fundamental wave reactive power Q (k).
S2, determining whether the fundamental wave reactive power q (k) at time k is equal to a threshold h, if so, the frequency f (k +1) at time k +1 is equal to the frequency f (k) at time k, that is, the frequency f (k +1) ═ f (k) at time k + 1, executing step S7, otherwise, executing step S3, where the threshold h is a constant greater than zero, and the value range of the threshold h is 1Var to 10 Var. If the fundamental reactive power q (k) is equal to the threshold h, the frequency is kept constant, whereas the frequency step is changed, thereby adjusting the frequency.
And S3, calculating the difference value delta Q of the fundamental wave reactive power at the moment k and the moment k-1, and calculating the frequency step length delta f according to the difference value delta Q of the fundamental wave reactive power. The frequency step size delta f is a change value, and the size of the frequency step size delta f is related to the size of the difference value delta Q of the fundamental wave reactive power. The frequency step length delta f is calculated by mainly adopting a piecewise function, fuzzy control or a neural network.
S4, judging whether the fundamental wave reactive power Q (k) at the moment k is larger than a threshold value h, if so, executing a step S5, otherwise, executing a step S6.
S5, adding the frequency f (k) in step S1 to the frequency step Δ f in step S3 to obtain the frequency f (k +1) at the time of k +1, and executing step S7; that is, the frequency f (k +1) at the time k +1 is f (k) +. af.
S6, subtracting the frequency step Δ f from step 3 from the frequency f (k) in step S1 to obtain the frequency f (k +1) at the time of k +1, and executing step S7; that is, the frequency f (k +1) ═ f (k) — Δ f at the time k + 1.
And S7, outputting the frequency f (k +1) at the moment of k +1 to a control unit to regulate and control the main circuit, and ensuring that the induction heating circuit is always in a weak induction resonance state.
Embodiment 3, as shown in fig. 3, a quasi-resonant control system for induction heating includes a control unit, a detection filter circuit, a photoelectric isolation and drive circuit, and a main circuit; the control unit is connected with the detection filter circuit, the control unit is connected with the photoelectric isolation and drive circuit, the photoelectric isolation and drive circuit is connected with the main circuit, and the main circuit is connected with the detection filter circuit. The control unit adopts a DSP control chip, the main circuit comprises an H-bridge circuit and an induction heating circuit, the middle points of two branches of the H-bridge circuit are respectively connected with the induction heating circuit, the H-bridge circuit is connected with a photoelectric isolation and drive circuit, and the induction heating circuit is connected with a detection filter circuit. The DSP control chip receives the output voltage and current from the current and voltage group detection circuit, then calculates the output reactive power, and adjusts the system from high frequency to low frequency in a weak inductive resonance state by utilizing a variable step reactive power trend 0 frequency tracking method. The sampling filter circuit comprises a detection circuit and a conditioning circuit, wherein the detection circuit adopts a voltage and current Hall sensor, and the conditioning circuit adopts a second-order Butterworth low-pass filter circuit. The conditioning circuit conditions the signal to 0-3V according to the characteristics of the AD module in the DSP control circuit, and increases the amplitude limiting function to ensure that the signal is within the signal range which can be accepted by the AD module in the DSP control circuit, thereby preventing the damage to the DSP caused by overlarge signal voltage.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (6)
1. A quasi-resonance control method for induction heating is characterized by comprising the following steps:
s1, collecting the voltage u (k) and the current i (k) output by the main circuit at the moment k by using a detection circuit, calculating the fundamental wave reactive power Q (k) at the moment k, and recording the frequency f (k) at the moment k;
s2, judging whether the fundamental wave reactive power Q (k) at the moment k is equal to a threshold h, if so, judging whether the frequency f (k +1) at the moment k +1 is equal to the frequency f (k) at the moment k, executing a step S7, and otherwise, executing a step S3, wherein the threshold h is a constant greater than zero;
s3, calculating a difference value delta Q of the fundamental wave reactive power at the moment k and the moment k-1, and calculating a frequency step length delta f according to the difference value delta Q of the fundamental wave reactive power;
s4, judging whether the fundamental wave reactive power Q (k) at the moment k is larger than a threshold value h, if so, executing a step S5, otherwise, executing a step S6;
s5, adding the frequency f (k) in step S1 to the frequency step Δ f in step S3 to obtain the frequency f (k +1) at the time of k +1, and executing step S7;
s6, subtracting the frequency step Δ f from step 3 from the frequency f (k) in step S1 to obtain the frequency f (k +1) at the time of k +1, and executing step S7;
and S7, outputting the frequency f (k +1) at the moment of k +1 to the control unit to regulate and control the main circuit.
2. The quasi-resonance control method for induction heating according to claim 1, wherein the calculation method of the fundamental wave reactive power q (k) at the time k in step S1 is:
s11, collecting voltage u of main circuit at moment kα(k) And current iα(k) Voltage uα(k) And current iα(k) Respectively phase-shifted by 90 degrees to obtain a voltage uβ(k) And current iβ(k)；
S12, converting the voltage u on the coordinate system alpha betaα(k) And voltage uβ(k) Obtaining a voltage u (k) on a coordinate system dq through coordinate transformation;
s13, converting the current i in the coordinate system alpha betaα(k) And current iβ(k) Obtaining current i (k) on a coordinate system dq through coordinate transformation;
s14, calculating power W (k) on a coordinate system dq according to the voltage u (k) in the step S12 and the current i (k) in the step S13;
and S15, dividing the power W (k) obtained in the step S14 into active power p (k) and reactive power q (k), and performing low-pass filtering on the reactive power q (k) to obtain fundamental wave reactive power Q (k).
3. The quasi-resonant control method for induction heating according to claim 2, wherein the power w (k) in step S14 is: w (k) u (k) i (k), w (k) p (k) + q (k).
4. The quasi-resonance control method for induction heating according to claim 1, wherein the frequency step Δ f in step S3 is a variation value, and the magnitude of the frequency step Δ f is related to the magnitude of the difference Δ Q of the fundamental wave reactive power.
5. The quasi-resonance control method for induction heating according to claim 1 or 4, wherein the frequency step Δ f is calculated by using a piecewise function, fuzzy control or a neural network.
6. The control system of the quasi-resonant control method for induction heating according to claim 1, comprising a control unit, a detection filter circuit, a photoelectric isolation and drive circuit and a main circuit; the control unit is connected with the detection filter circuit, the control unit is connected with the photoelectric isolation and drive circuit, the photoelectric isolation and drive circuit is connected with the main circuit, and the main circuit is connected with the detection filter circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910759576.9A CN110446290B (en) | 2019-08-16 | 2019-08-16 | Quasi-resonance control method for induction heating |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910759576.9A CN110446290B (en) | 2019-08-16 | 2019-08-16 | Quasi-resonance control method for induction heating |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110446290A CN110446290A (en) | 2019-11-12 |
| CN110446290B true CN110446290B (en) | 2021-05-14 |
Family
ID=68436106
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910759576.9A Active CN110446290B (en) | 2019-08-16 | 2019-08-16 | Quasi-resonance control method for induction heating |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110446290B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113733536A (en) * | 2021-09-08 | 2021-12-03 | 南通三信塑胶装备科技股份有限公司 | Method for automatically debugging resonance frequency of corona machine |
| CN114679070B (en) * | 2022-04-13 | 2023-02-03 | 深圳市京泉华科技股份有限公司 | Tidal energy control system and control method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104770059A (en) * | 2012-10-30 | 2015-07-08 | 三井造船株式会社 | Inductive heating device, method for controlling inductive heating device, and program |
| CN107727927A (en) * | 2017-12-01 | 2018-02-23 | 江苏科技大学 | A kind of sensing heating levelling machine frequency converter Resonance detector and frequency-tracking system |
| CN109246875A (en) * | 2018-10-09 | 2019-01-18 | 三英精控（天津）仪器设备有限公司 | Multi-functional boosting resonant heating circuit |
-
2019
- 2019-08-16 CN CN201910759576.9A patent/CN110446290B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104770059A (en) * | 2012-10-30 | 2015-07-08 | 三井造船株式会社 | Inductive heating device, method for controlling inductive heating device, and program |
| CN107727927A (en) * | 2017-12-01 | 2018-02-23 | 江苏科技大学 | A kind of sensing heating levelling machine frequency converter Resonance detector and frequency-tracking system |
| CN109246875A (en) * | 2018-10-09 | 2019-01-18 | 三英精控（天津）仪器设备有限公司 | Multi-functional boosting resonant heating circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110446290A (en) | 2019-11-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2019153308A1 (en) | Ripple optimization control method for pfc circuit output voltage and related circuit | |
| CN108656994B (en) | Electric automobile IPT system of variable capacitance | |
| CN101295878A (en) | Current control method and device of flexible DC power transmission current transformer | |
| CN112117888B (en) | Control method of totem-pole rectifier based on zero crossing point current distortion online compensation | |
| CN110446290B (en) | Quasi-resonance control method for induction heating | |
| CN111049392B (en) | Double-active-bridge expanded phase-shifting minimum reflux power control method based on coordinate transformation | |
| CN109004883A (en) | A kind of busbar voltage low-pressure area control method of small capacitances motor driven systems | |
| CN104579091B (en) | Direct torque control device and method | |
| CN109004849B (en) | PWM rectifier fast response control method for electric servo loading system | |
| CN112953250A (en) | Power supply control method, power supply module and storage medium | |
| CN111969877B (en) | Control method and device of half-bridge inverter | |
| CN102959848B (en) | Rectification circuit device | |
| CN113054859A (en) | High-frequency single-phase full-bridge inverter and control method thereof | |
| Bode et al. | A novel hysteresis current controller for multilevel single phase voltage source inverters | |
| CN102969716A (en) | Method for controlling active power filter of marine electrical network | |
| Yanfeng et al. | The comparative analysis of PI controller with PR controller for the single-phase 4-quadrant rectifier | |
| Ren et al. | Robust adaptive control of a CACZVS three-phase PFC converter for power supply of silicon growth furnace | |
| CN110011524B (en) | Control method, device and equipment for harmonic suppression and readable storage medium | |
| CN204190642U (en) | Based on the load phase adjuster of current follow-up control | |
| CN108322069B (en) | Three-phase current source type power supply and load integrated control system | |
| CN112542978B (en) | Motor driving system based on bidirectional staggered parallel DC-DC inverter | |
| Feng et al. | The super-twisting sliding mode control for half-bridge three-level LLC resonant converter | |
| CN206820538U (en) | Three arm rectification adversers concatenate load type UPS circuits | |
| CN109067230A (en) | A kind of online adaptive dead zone removing method of SiC MOSFET inverter | |
| CN116545261B (en) | DC converter for micro-grid, control method and storage medium |
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 |