CN103737155B - Single-phase full-bridge inversion topological magnetic biasing staged processing circuit and method - Google Patents
Single-phase full-bridge inversion topological magnetic biasing staged processing circuit and method Download PDFInfo
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- CN103737155B CN103737155B CN201410004776.0A CN201410004776A CN103737155B CN 103737155 B CN103737155 B CN 103737155B CN 201410004776 A CN201410004776 A CN 201410004776A CN 103737155 B CN103737155 B CN 103737155B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/10—Other electric circuits therefor; Protective circuits; Remote controls
- B23K9/1006—Power supply
- B23K9/1043—Power supply characterised by the electric circuit
- B23K9/1056—Power supply characterised by the electric circuit by using digital means
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Abstract
The invention discloses a single-phase full-bridge inversion topological magnetic biasing staged processing circuit and method. The processing circuit comprises a first sensor for acquiring primary-side current and performing signal processing and signal conditioning modules, wherein the first sensor and the signal conditioning modules are connected with a proportional regulator; the primary-side current processed by using the proportional regulator is partitioned into two paths, one path enters a first comparator together with a preset given signal through a channel A, the first comparator is connected with a first signal conditioning module, and the first signal conditioning module is connected with a digital controller; the other path enters a second comparator together with a processed output current signal through a channel B, the second comparator is connected with a second signal conditioning module, and the second signal conditioning module is connected with the digital controller. The processing circuit is quick in dynamic response and high in reliability. Staged processing is performed in combination with the characteristics of an analog circuit and digital control according to the severity of magnetic biasing, the processing requirement of a rapid magnetic biasing phenomenon can be met fully, and the system reliability and security are enhanced greatly.
Description
Technical field
The present invention relates to a kind of magnetic bias classification treatment circuit, particularly relate to single-phase full bridge inversion topological magnetic bias classification treatment circuit and method.
Background technology
Single-phase full bridge inverter circuit, is generally made up of four device for power switching and transformer.Compare half-bridge circuit structure, the electric current that each device for power switching bears reduces half, and therefore, full bridge inverter is the first-selection of high-power energy conversion equipment, and such as output current adopts this structure substantially at the inversion welding source of more than 400A.But this circuit does not possess the ability suppressing transformer bias, causes system reliability low.
When the impulse amplitude be applied in two PWM half periods on main transformer or width not etc. time, will DC component be produced in transformer.The sharply change of exciting current, makes magnetization curve Severe distortion, produces transformer bias phenomenon, causes primary current overcurrent, the thermal losses of power device etc. is strengthened, causes its permanent damage, jeopardize security of system.But, now in output current, generally can not produce obvious characteristic signal, and during system magnetic bias, primary side current of transformer skyrockets the time generally within several microsecond, and the time of therefore bias magnetic signal detection and control process, The faster the better.
Mainly adopt methods such as increasing block capacitor, increase transformer magnetic circuit air gap, series connection linear inductance to suppress magnetic bias at present, but the existence of these methods easily increase volume of transformer, cannot eliminate magnetic bias completely, reduce the problems such as system dynamic response.Application number is the patent of invention " inversion welding source Intelligent magnetic biasing detection and treatment device " of 201110352645.8, propose a kind of new magnetic bias real-time detection circuit, the magnetic bias moment that the method can detect in time and intensity, and take correspondingly control strategy by digitial controller, but when magnetic bias situation is very serious, to cause system failure in several microsecond, the method will be difficult to safety and the reliability of system in this serious magnetic bias situation of guarantee.
Summary of the invention
For solving the deficiency that prior art exists, the invention discloses single-phase full bridge inversion topological magnetic bias classification treatment circuit and method, the method is by distinguishing the magnetic bias order of severity, be divided into serious magnetic bias and general magnetic bias two kinds of ranks, take classification treatment measures, while can ensureing security of system in time, the magnetic bias moment produced according to circuit and power, the control strategy that programming realization is different in digitial controller, reach and eliminate magnetic bias scene, improve the object of system reliability, can be widely used in the system based on full bridge inverter structure, there is important practical significance and using value.
For achieving the above object, concrete scheme of the present invention is as follows:
Single-phase full bridge inversion topological magnetic bias classification treatment circuit, comprise for gathering primary current and carrying out first sensor and the Signal-regulated kinase of signal transacting, first sensor and Signal-regulated kinase are connected with proportional controller, primary current signal after proportional controller process divides two-way, leading up to A channel and preset Setting signal enters the first comparator, first comparator is connected with the first Signal-regulated kinase, and the first Signal-regulated kinase is connected with digitial controller;
Separately lead up to channel B with process after output current signal enter the second comparator, the second comparator is connected with secondary signal conditioning module, and secondary signal conditioning module is connected with digitial controller.
Output current signal after described process is the signal through the second sensor and Signal-regulated kinase and adder process.
Described adder is also connected with regulation voltage input module.
Described proportional controller is by resistance R7, R8 and operational amplifier U
1_1Bcomposition, proportional controller is for regulating the amplitude of primary current signal.
Described preset Setting signal is UP through resistance R11 and R12 dividing potential drop and the filtered signal of C2.
Described regulation voltage input module is by resistance R1 with for the potentiometer R2 of dividing potential drop and form for filter capacitor C1.
Described adder is by resistance R3, R4, R5, R6 and operational amplifier U
1_1Acomposition.
Described first Signal-regulated kinase is pull-up resistor R10; Described secondary signal conditioning module is pull-up resistor R9.
Signal-regulated kinase in described first sensor and Signal-regulated kinase, by rectifier bridge D1_1, R13, R12 " and operational amplifier U
1_1Ccomposition; Signal-regulated kinase in described second sensor and Signal-regulated kinase, by R11 " and operational amplifier U
1_1Dcomposition.
Single-phase full bridge inversion topological magnetic bias hierarchical processing method, comprises the following steps:
Obtain primary side current of transformer signal by current sensor, and convert in-phase pulse current signal to through signal conditioning circuit, through proportional controller, the primary current signal that output amplitude is adjustable, compares with preset given signal;
Meanwhile, by current sensor real-time acquisition system output current, and convert voltage signal to, the feedback signal adjustable by output amplitude after regulation voltage input module and adder process;
When primary current signal is greater than preset given signal, for serious magnetic bias, primary current signal will by tributary circuit A, export the PWM locking signal of high level through the first comparator, then through pull-up resistor R10, ensure that this signal inerrably sends into digitial controller process, the priority of this situation is set to the highest by digitial controller, once receive this signal, driving pulse will be blocked at once, ensure security of system;
When primary current signal is less than preset given signal, for general magnetic bias, primary current signal by path B, will compare with treated output current signal, bias magnetic signal is exported by the first comparator, after pull-up resistor R9 process, send into digitial controller, the position that digitial controller occurs according to bias magnetic signal and power, realize the quick adjustment of PWM dutycycle, transformer is hightailed saturated, recover normal hysteresis curve workspace, reach the object eliminating magnetic bias.
Described bias magnetic signal contains position and the width of bias magnetic signal generation.
Digitial controller can adopt single-chip microcomputer, DSP or FPGA, and The faster the better for the processing speed of certain controller.No matter which kind of mode, all will ensure the limit priority of this program.Build because magnetic bias testing circuit all have employed analog device, thus can be timely, correct detect bias magnetic signal; And the bias magnetic signal detected is sent to digitial controller, able to programmely realize various control strategy, adapt to the bias phenomenon process under different process, different occasion and application background.
Beneficial effect of the present invention:
This method makes full use of the no-load voltage ratio relation of energy conversion system input and output and advanced digital control technology, has the advantage that measure is in the past incomparable:
(1) dynamic response is fast, and reliability is high.In conjunction with analog circuit and numerically controlled feature, according to the magnetic bias order of severity, carry out classification process, will can meet the processing requirements of quick bias phenomenon completely, significantly elevator system reliability and security.Method simple and easy and be convenient to realize and commercial application.
(2) highly versatile, pervasive degree is high.This method is suitable for the most of energy conversion system based on single-phase full bridge inverter circuit structure, such as, in welding system, be no matter in source of welding current design process corresponding to the welding procedures such as direct current weldering, impulse welding, cold metal transfer weldering, all can continue to use this scheme.
(3) flexible and changeable, intelligent good.This method can according to the diversity of practical engineering application and particularity, and the control strategy that programming realization is different in digitial controller, processes automatically according to bias phenomenon, system is possessed intelligent.
Accompanying drawing explanation
Fig. 1 overall structure schematic diagram of the present invention;
Fig. 2 physical circuit connection diagram of the present invention.
Detailed description of the invention:
Below in conjunction with accompanying drawing, the present invention is described in detail:
As shown in Figure 1, single-phase full bridge inversion topological magnetic bias classification treatment circuit, comprise for gathering primary current and carrying out first sensor and the Signal-regulated kinase of signal transacting, first sensor and Signal-regulated kinase are connected with proportional controller, primary current signal after proportional controller process divides two-way, leading up to A channel and preset Setting signal enters the first comparator, and the first comparator is connected with the first Signal-regulated kinase, and the first Signal-regulated kinase is connected with digitial controller;
Separately lead up to channel B with process after output current signal enter the second comparator, the second comparator is connected with secondary signal conditioning module, and secondary signal conditioning module is connected with digitial controller.
Output current signal after described process is the signal through the second sensor and Signal-regulated kinase and adder process.Described adder is also connected with regulation voltage input module.Signal-regulated kinase in described first sensor and Signal-regulated kinase, by rectifier bridge D1_1, R13, R12 " and operational amplifier U
1_1Ccomposition, wherein rectifier bridge D1_1 and resistance R13 forms homophase rectifier, realizes the primary current signal rectification of interchange to become in-phase signal, R12 " and operational amplifier U
1_1Cform follower, realize impedance matching, ensure that subsequent conditioning circuit normally works; Signal-regulated kinase in described second sensor and Signal-regulated kinase is by R11 " and operational amplifier U
1_1Dthe follower of composition, realizes impedance matching, ensures that subsequent conditioning circuit normally works.Proportional controller is by resistance R7, R8 and operational amplifier U
1_1Bcomposition, proportional controller is for regulating the amplitude of primary current signal.Preset Setting signal is UP through resistance R11 and R12 dividing potential drop and the filtered signal of C2.Regulation voltage input module is by resistance R1 with for the potentiometer R2 of dividing potential drop and form for filter capacitor C1.Adder is by resistance R3, R4, R5, R6 and operational amplifier U
1_1Acomposition.First Signal-regulated kinase is pull-up resistor R10; Described secondary signal conditioning module is pull-up resistor R9.
Because transformer bias will cause primary current overcurrent, therefore obtain the primary current signal after processing by sensor, signal conditioning circuit and proportional controller.If system creates serious magnetic bias, be difficult to regulate and eliminate, primary current signal by tributary circuit A, directly will compare with preset Setting signal, produces system protection signal, by digitial controller Immediate management, closes PWM driving pulse, safeguards system safety.If general magnetic bias, primary current signal will by path B, compare with the system output current signal obtained through sensor, signal condition and adder/subtracter etc., bias magnetic signal is exported by comparator, contain position and the width of bias magnetic signal generation, after signal condition link, send into digitial controller.The position occurred according to bias magnetic signal and power, the quick adjustment of programming realization PWM dutycycle, makes transformer hightail saturated, recovers normal hysteresis curve workspace, reaches the object eliminating magnetic bias.
As shown in Figure 2, primary side current of transformer signal is obtained, via rectifier bridge D1_1, R13, R12 by current sensor " and operational amplifier U
1_1Cthe homophase of composition adjusts and follows circuit, the AC signal of primary current is converted to in-phase pulse current signal U
i1, via resistance R7, R8 and operational amplifier U
1_1Bthe proportional controller formed, the former limit fed-back current signals that output amplitude is adjustable; Meanwhile, after resistance R11 and R12 dividing potential drop and C2 filtering, export preset Setting signal, i.e. the maximum former limit overcurrent value that can tolerate of energy conversion system, pull-up resistor R10 is used for guaranteeing that controller can receive serious bias magnetic signal accurately; Meanwhile, by current sensor real-time acquisition system output current, and pass through by R11 " and operational amplifier U
1_1Dthe circuit conversion of following of composition becomes voltage signal U
i2, and by the U produced after resistance R1 and potentiometer R2 dividing potential drop and electric capacity C1 filtering
mtogether, via resistance R3, R4, R5, R6 and operational amplifier U
1_1Athe adder formed adds up, the current feedback signal that output amplitude is adjustable, and wherein the effect of potentiometer R2 regulates feedback current amplitude, determines the critical point that bias phenomenon occurs.
When transformer bias causes former limit overcurrent larger, serious threat is to security of system, namely after exceeding setting value, to obtain and the primary side current of transformer converted through path A and its maximum set value, will compare through comparator U2_1A, produce PWM locking signal and send into digitial controller, the priority of this situation is set to the highest by controller, once receive this signal, driving pulse will be blocked at once, ensure security of system.If transformer bias degree is in adjustable extent, to obtain and the primary side current of transformer converted through path B and output current signal, will compare through comparator U2_1B, bias magnetic signal can be obtained in time and deliver to digitial controller and process.Pull-up resistor R9 is used for guaranteeing that controller can receive bias magnetic signal accurately.Controller then after detecting bias magnetic signal, can adjust the dutycycle of follow-up PWM driving pulse, makes main transformer recover normal hysteresis curve workspace, reaches the object eliminating magnetic bias, improves the stability of a system and reliability.
Claims (6)
1. the processing method of single-phase full bridge inversion topological magnetic bias classification treatment circuit, described single-phase full bridge inversion topological magnetic bias classification treatment circuit, comprise for gathering primary current and carrying out first sensor and the Signal-regulated kinase of signal transacting, first sensor and Signal-regulated kinase are connected with proportional controller, primary current signal after proportional controller process divides two-way, leading up to A channel and preset Setting signal enters the first comparator, first comparator is connected with the first Signal-regulated kinase, and the first Signal-regulated kinase is connected with digitial controller;
Separately lead up to channel B with process after output current signal enter the second comparator, the second comparator is connected with secondary signal conditioning module, and secondary signal conditioning module is connected with digitial controller;
Output current signal after described process is the signal through the second sensor and Signal-regulated kinase and adder process;
Described adder is also connected with regulation voltage input module;
Described first Signal-regulated kinase is pull-up resistor R10; Described secondary signal conditioning module is pull-up resistor R9;
It is characterized in that, comprise the following steps:
Obtain primary side current of transformer signal by current sensor, and convert in-phase pulse current signal to through signal conditioning circuit, through proportional controller, the primary current signal that output amplitude is adjustable, compares with preset given signal;
Meanwhile, by current sensor real-time acquisition system output current, and convert voltage signal to, the feedback signal adjustable by output amplitude after regulation voltage input module and adder process;
When primary current signal is greater than preset given signal, for serious magnetic bias, primary current signal will by tributary circuit A, export the PWM locking signal of high level through the first comparator, then through pull-up resistor R10, ensure that this signal inerrably sends into digitial controller process, the priority of this situation is set to the highest by digitial controller, once receive this signal, driving pulse will be blocked at once, ensure security of system;
When primary current signal is less than preset given signal, for general magnetic bias, primary current signal by path B, will compare with treated output current signal, bias magnetic signal is exported by the second comparator, after pull-up resistor R9 process, send into digitial controller, the position that digitial controller occurs according to bias magnetic signal and power, realize the quick adjustment of PWM dutycycle, transformer is hightailed saturated, recover normal hysteresis curve workspace, reach the object eliminating magnetic bias;
Described bias magnetic signal contains position and the width of bias magnetic signal generation.
2. the processing method of single-phase full bridge inversion topological magnetic bias classification treatment circuit as claimed in claim 1, it is characterized in that, described proportional controller is by resistance R7, R8 and operational amplifier U
1_1Bcomposition, proportional controller is for regulating the amplitude of primary current signal.
3. the processing method of single-phase full bridge inversion topological magnetic bias classification treatment circuit as claimed in claim 1, is characterized in that, described preset Setting signal is reference voltage Up through resistance R11 and R12 dividing potential drop and the filtered signal of C2.
4. the processing method of single-phase full bridge inversion topological magnetic bias classification treatment circuit as claimed in claim 1, is characterized in that, described regulation voltage input module is by resistance R1 with for the potentiometer R2 of dividing potential drop and form for filter capacitor C1.
5. the processing method of single-phase full bridge inversion topological magnetic bias classification treatment circuit as claimed in claim 1, it is characterized in that, described adder is by resistance R3, R4, R5, R6 and operational amplifier U
1_1Acomposition.
6. the processing method of single-phase full bridge inversion topological magnetic bias classification treatment circuit as claimed in claim 1, is characterized in that, the Signal-regulated kinase in described first sensor and Signal-regulated kinase, by rectifier bridge D1_1, R13, R12 " and operational amplifier U
1_1Ccomposition; Signal-regulated kinase in described second sensor and Signal-regulated kinase, by R11 " and operational amplifier U
1_1Dcomposition.
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| CN105633918B (en) * | 2014-11-07 | 2019-02-12 | 北京时代科技股份有限公司 | A kind of diamagnetic saturation device of inverter |
| CN110943432B (en) * | 2019-11-07 | 2022-04-05 | 厦门拓宝科技有限公司 | Control device and method for restraining direct-current magnetic bias of single-phase power-frequency transformer |
| CN112039330B (en) * | 2020-09-09 | 2022-03-18 | 深圳市永联科技股份有限公司 | Method for solving magnetic bias |
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