Metal electro-plastic processing hybrid transformer and collaborative temperature control method

Abstract

This application relates to the field of power electronics technology and discloses a hybrid converter and a collaborative temperature control method for electroplastic treatment of metals. The converter includes a phase-shifted full-bridge circuit, a rectifier-filter circuit, a pulse generator circuit, and a bootstrap clamping power supply circuit. The phase-shifted full-bridge circuit is connected to the rectifier-filter circuit via a transformer, together forming the DC output side. The peak pulse side is composed of a pulse generator circuit that controls the current rise phase and a bootstrap clamping power supply circuit that controls the fall phase. This collaborative temperature control method is applied to the hybrid converter. This application solves the technical problem of the limitations of using a single current waveform in electroplasticity research in existing technologies.

Description

Technical Field

[0001] This application relates to the field of power electronics technology, specifically a hybrid converter and synergistic temperature control method for metal electroplastic treatment. Background Technology

[0002] With the increasing demands for metal properties driven by the development of aerospace, electronics, and other fields, traditional heat conduction-based metal processing methods are becoming increasingly demanding. These methods are complex, energy-intensive, and offer little improvement in metal properties, making them insufficient for the processing and production of high-end metal materials. Therefore, research on the electroplasticity of metal materials has emerged as a major direction for future development. Currently, there are no power supplies specifically designed for metal processing on the market; only power supplies with similar output parameters are available, primarily in DC or pulsed form. Pulsed power supplies, in particular, represent a blind spot in the study of metal electroplasticity. While theories such as electron wind, thermally activated strain rate, and induced magnetic field effects are used as primary starting points, none can fully and accurately quantify the specific impact of changes in current parameters on metal properties.

[0003] The analysis of the electroplasticity mechanism of metals mainly involves two aspects: thermal effects and electrical effects. Among these, the study of electrical effects is key to revealing its essential mechanism. To accurately investigate the role of electrical effects, it is necessary to effectively distinguish them from thermal effects. It is generally believed that the effect of direct current is primarily thermal; while the instantaneously applied high-energy pulsed current (100~1000 A / mm²) is the main means of highlighting electrical effects. Currently, the power supplies widely used in metal electroplastic processing are mostly in the form of direct current, and the application of pulsed current is relatively limited. In practice, capacitor energy storage is often used as its instantaneous energy source. Such power supplies generally suffer from drawbacks such as severe pulse tailing, large size, and high heat loss. Furthermore, their switching devices mostly use thyristors, which also have certain limitations in terms of controllability and operating frequency. Summary of the Invention

[0004] The purpose of this application is to provide a hybrid converter and synergistic temperature control method for metal electroplastic processing, so as to solve the technical problem of the limitation of single current waveform in electroplasticity research in the prior art.

[0005] To achieve the above objectives, this application provides a hybrid converter with metal electroplastic treatment, including a phase-shifted full-bridge circuit, a rectifier and filter circuit, a pulse generation circuit, and a bootstrap clamping power supply circuit; wherein: the phase-shifted full-bridge circuit is connected to the rectifier and filter circuit through a transformer, together forming the DC output side; the peak pulse side is composed of a pulse generation circuit divided into a current rising phase and a bootstrap clamping power supply circuit controlled by the falling phase.

[0006] Preferably, the phase-shifted full-bridge inverter circuit includes diodes. ,capacitance Switching transistor Switching transistor Switching transistor Switching transistor ,capacitance ,capacitance ,capacitance ,capacitance and inductor Among them: diodes With capacitor This is the input section of the inverter circuit; the switching transistor. to A full-bridge inverter circuit is constructed, with capacitors connected in parallel on each side. to ,inductance Connected in series with the primary transformer, making the inductance The capacitor connected in parallel with the switch forms a soft switch.

[0007] Preferably, the rectifier filter circuit includes diodes. ,diode ,diode ,inductance and capacitor Among them: diodes and Construct a full-wave rectifier circuit, with a series inductor and parallel capacitors A diode is connected in series at the output terminal. This makes the output current on each side relatively independent.

[0008] Preferably, the pulse generating circuit includes a switching transistor. Switching transistor Switching transistor Switching transistor ,diode ,diode and capacitor Among them: switching transistors to Construct a full-bridge pulse generator circuit, with output diodes With capacitor The parallel connection provides energy for the pulse peak, and the output series-side diodes... This makes the output current relatively independent.

[0009] Preferably, the bootstrap clamping power supply circuit includes a diode. ,diode ,inductance Switching transistor and capacitor Among them: diodes ,inductance Switching transistor With capacitor Series connection, diode Parallel to inductor With switching transistor middle.

[0010] Preferably, metallic materials and stray inductance include inductors. and resistance Among them: inductance and resistance It is represented by a series structure, which represents the actual load situation.

[0011] Preferably, the DC output side is equipped with a corresponding control method, including:

[0012] Acquire the output current of the rectifier and filter circuit The size serves as feedback and sets the DC output size. The difference is calculated and transmitted to the preset proportional-integral module. After limiting, the dead-time, direction shift, and inversion control are applied to the four switches of the full-bridge inverter circuit. to This controls the output circuit.

[0013] Preferably, a corresponding control method is provided on the pulse peak side, including:

[0014] The rising phase is when the peak current value is collected. With the set peak The difference between the magnitudes is fed into the proportional-integral module to control the switching transistor. With switching transistor The pulse width is adjusted to regulate the output peak value and capacitor voltage. This is in the switching transistor With switching transistor Adjust the switching transistor under conduction conditions The conduction time is adjusted to regulate the energy feedback amount, and to perform the following: Flexible adjustment.

[0015] Preferably, the hybrid converter is equipped with a corresponding collaborative temperature control method, including:

[0016] DC side by collecting output current As a feedback control variable, the DC power is calculated in conjunction with the load parameters; the power calculation on the peak pulse side is performed separately for the rising and falling phases to obtain the peak pulse power.

[0017] The total power is the sum of the DC power and the peak pulse power;

[0018] In total power control, when a peak pulse power is applied, the DC power needs to be adjusted accordingly to stabilize the total power at the set value. DC power is adjusted by controlling the phase angle of the phase-shifted full-bridge circuit; peak pulse power is adjusted by changing the pulse frequency or adjusting the falling platform voltage to control the rate of current decrease.

[0019] Preferably, the peak pulse power is calculated by taking the circuit inductance, input voltage, falling plateau voltage, set peak current and pulse frequency, and obtaining the average power of this part by the current square integration method.

[0020] Beneficial effects: The hybrid converter and synergistic temperature control method for metal electroplasticity treatment in this application provide a flexible combination of DC and pulse outputs, allowing for a more systematic exploration of the change mechanism of metal electroplasticity; the addition of a bootstrap clamping power supply circuit greatly accelerates and controls the discharge process, thereby reducing the thermal effect caused by the pulse and highlighting the electrical effect, achieving decoupling between electricity and heat, and making the electroplasticity research process clearer; the temperature control uses both DC and peak values ​​for synergistic temperature control, highlighting the influence of the peak electrical effect on metal electroplasticity at a fixed temperature. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is an overall topology diagram of a hybrid converter with metal electroplastic treatment provided in an embodiment of this application;

[0023] Figure 2 A topology diagram of the phase-shifted full-bridge inverter circuit provided in the embodiments of this application;

[0024] Figure 3 A topology diagram of the rectifier filter circuit provided in the embodiments of this application;

[0025] Figure 4 This is a topology diagram of the pulse generation circuit provided in the embodiments of this application;

[0026] Figure 5 A topology diagram of the bootstrap clamp power supply circuit provided in an embodiment of this application;

[0027] Figure 6 A topological diagram of the metallic material and stray inductor provided in the embodiments of this application;

[0028] Figure 7 A block diagram of a DC-side control method for a hybrid converter provided in an embodiment of this application;

[0029] Figure 8 A block diagram of a pulse peak-side control method for a hybrid converter provided in an embodiment of this application;

[0030] Figure 9 A logic diagram for the coordinated temperature control of a hybrid converter provided in an embodiment of this application;

[0031] Figure 10 Simulation waveforms provided for embodiments of this application Figure 1 ;

[0032] Figure 11 Simulation waveforms provided for embodiments of this application Figure 2 ;

[0033] Figure 12 Simulation waveforms provided for embodiments of this application Figure 3 .

[0034] The implementation, functional features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0035] The technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0036] In this document, the term "comprising" is intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0037] Unlike existing single DC or pulse power supplies, this embodiment discloses a hybrid converter and a collaborative temperature control method for metal electroplastic treatment. It provides a hybrid converter for metal electroplastic treatment that can study the metal plasticity changes under single DC or pulse conditions, and can also explore the electroplasticity under DC temperature control with instantaneous high-energy pulse injection. The addition of a bootstrap clamping power supply circuit to the topology can accelerate and control the pulse tail time, thereby significantly reducing the thermal effects caused by instantaneous high-energy pulses.

[0038] The hybrid converter with metal electroplastic treatment disclosed in this embodiment will now be described in detail.

[0039] Reference Figure 1 , Figure 1 The overall topology diagram of the hybrid converter with metal electroplastic treatment provided in the embodiments of this application is shown.

[0040] like Figure 1 As shown, this embodiment discloses a hybrid converter with metal electroplastic treatment, including: a phase-shifted full-bridge circuit, a rectifier and filter circuit, a pulse generation circuit, and a bootstrap clamping power supply circuit; wherein: the phase-shifted full-bridge circuit is connected to the rectifier and filter circuit through a transformer to jointly form the DC output side; the peak pulse side is composed of a pulse generation circuit divided into a current rising phase and a bootstrap clamping power supply circuit controlled by the falling phase.

[0041] In this specific application, the phase-shifted full-bridge circuit and the rectifier-filter circuit are the output terminals of the DC thermal effect, while the pulse generation circuit and the bootstrap clamping power supply circuit highlight the influence of the pulse electrical effect. The overall topology of the hybrid converter in this embodiment combines the DC thermal effect and the peak electrical effect in its output waveform, overcoming the limitations of electroplasticity studies under a single current waveform. Specifically:

[0042] The DC side uses a phase-shifted full-bridge circuit to control the current magnitude, aiming to have a fixed output current under a wide range of input voltages;

[0043] The peak-side topology can inject high-energy pulses instantaneously on a DC basis to study the electrical effects of metallic materials at phase transition temperatures; the bootstrap clamping power supply circuit can utilize the energy of stray inductance in the line to provide a higher clamping voltage for the pulse discharge process, thereby accelerating the discharge speed and reducing the heat generated by the peak pulse.

[0044] Furthermore, the coordinated temperature control uses the current area method to back-calculate the output power to achieve precise temperature control.

[0045] Reference Figure 2 , Figure 2 This is a topology diagram of the phase-shifted full-bridge inverter circuit provided in an embodiment of this application.

[0046] like Figure 2 As shown, the phase-shifted full-bridge inverter circuit includes diodes. ,capacitance Switching transistor Switching transistor Switching transistor Switching transistor ,capacitance ,capacitance ,capacitance ,capacitance and inductor Among them: diodes With capacitor This is the input section of the inverter circuit; the switching transistor. to A full-bridge inverter circuit is constructed, with capacitors connected in parallel on each side. to ,inductance Connected in series with the primary transformer, making the inductance The capacitor connected in parallel with the switch forms a soft switch.

[0047] Reference Figure 3 , Figure 3 This is a topology diagram of the rectifier filter circuit provided in an embodiment of this application.

[0048] like Figure 3 As shown, the rectifier filter circuit includes diodes. ,diode ,diode ,inductance and capacitor Among them: diodes and Construct a full-wave rectifier circuit, with a series inductor and parallel capacitors A diode is connected in series at the output terminal. This makes the output current on each side relatively independent.

[0049] Reference Figure 4 , Figure 4 This is a topology diagram of the pulse generation circuit provided in an embodiment of this application.

[0050] like Figure 4 As shown, the pulse generation circuit includes a switching transistor. Switching transistor Switching transistor Switching transistor ,diode ,diode and capacitor Among them: switching transistors to Construct a full-bridge pulse generator circuit, with output diodes With capacitor The parallel connection provides energy for the pulse peak, and the output series-side diodes... This also makes the output current relatively independent.

[0051] Reference Figure 5 , Figure 5 The topology diagram of the bootstrap clamp power supply circuit provided in the embodiments of this application is shown.

[0052] like Figure 5 As shown, the bootstrap clamp power supply circuit includes diodes. ,diode ,inductance Switching transistor and capacitor Among them: diodes ,inductance Switching transistor With capacitor Series connection, diode Parallel to inductor With switching transistor middle.

[0053] Reference Figure 6 , Figure 6 The diagram shows the topology of the metal material and stray inductor provided in the embodiments of this application.

[0054] like Figure 6 As shown, metallic materials and stray inductance include inductance. and resistance Among them: inductance and resistance It is represented by a series structure, which represents the actual load situation.

[0055] In the specific application of this embodiment, the phase-shifted full-bridge inverter circuit and the rectifier filter circuit are connected through a transformer to jointly form the DC output side.

[0056] In the specific application of this embodiment, the pulse peak side consists of a pulse generation circuit and a bootstrap clamping power supply circuit, which are responsible for controlling the rise and fall phases of the pulse peak, respectively.

[0057] The DC-side output control is based on the phase angle control of the inverter circuit, which can ensure the stability of the output current over a wide range of voltage inputs.

[0058] Pulse peak control during the rising phase to switch the transistor With switching transistor The peak current is controlled by the pulse width during the on-state, and the capacitance is used during the descent phase. The higher discharge platform provided accelerates current decay, thereby effectively suppressing tail current and reducing the resulting heat loss, making the heat power generated during the pulse process more controllable.

[0059] like Figure 5 The bootstrap clamping power supply circuit shown is key to making the peak pulse descent process controllable. The capacitor voltage in the bootstrap clamping power supply circuit... The magnitude of the discharge current is independent of the input voltage source and depends only on the energy in the circuit. Compared with the traditional full-bridge pulse circuit, its discharge process can be independently controlled and accelerated, especially under low voltage and large stray inductance conditions, which significantly improves the tail current.

[0060] In the switching transistor With switching transistor After being turned off, the residual current in the stray inductor flows to the capacitor through the freewheeling path. Charging. When the next pulse cycle arrives, the switching transistor... When the circuit is turned on, current flows through the inductor. Limited and fed back to capacitor Repeat the above charging process to increase the capacitor voltage. It rises to a higher level, thereby accelerating the decay of the pulse current. The voltage value can be adjusted by adjusting the inductor. With capacitor The parameters can be set, or the switching transistor can be controlled. The conduction time is adjusted to regulate the energy feedback, thereby achieving the desired effect. Flexible adjustment.

[0061] Reference Figure 7 , Figure 7 A block diagram of a DC-side control method for a hybrid converter provided in an embodiment of this application.

[0062] like Figure 7 As shown, the implementation details of the DC-side control method for the hybrid converter in this embodiment are as follows: The output current of the rectifier filter circuit is collected. The size serves as feedback and sets the DC output size. The difference is calculated and transmitted to the preset PI (Proportional-Integral) module. After limiting (LIM), dead-time, shift, and inversion (NOT) are applied to control the four switches of the full-bridge inverter circuit. to This enables control of the output circuit.

[0063] Reference Figure 8 , Figure 8 A block diagram of a pulse peak-side control method for a hybrid converter provided in an embodiment of this application.

[0064] like Figure 8 As shown, the rising phase is when the peak current value is collected. With the set peak The difference between the values ​​is calculated and fed into the PI controller to control... and The pulse width is adjusted to regulate the magnitude of the output peak. That is in and Adjust according to the conduction condition The conduction time is adjusted to regulate the energy feedback, thereby achieving the desired effect. Flexible adjustment.

[0065] Reference Figure 9 , Figure 9A logic diagram for the coordinated temperature control of a hybrid converter provided in an embodiment of this application.

[0066] like Figure 9 As shown, the implementation details of the coordinated temperature control of the hybrid converter are as follows: On the DC side, the output current is collected as a feedback control quantity, and the DC power is calculated by combining it with known load parameters. The power calculation on the peak pulse side is performed separately for the rising and falling phases: under the condition that the circuit inductance, input voltage, falling plateau voltage, set peak current, and pulse frequency are known, the average power of this part is obtained by the current square integral method. The total system power is the sum of DC power and peak pulse power. In total power control, when the peak pulse power is added, the DC power needs to be adjusted accordingly to stabilize the total power at the set value. The adjustment of DC power is achieved by controlling the phase angle of the phase-shifted full bridge; the adjustment of peak pulse power can be achieved by changing the pulse frequency or adjusting the falling plateau voltage to control the current falling rate, given the peak current setting.

[0067] Reference Figures 10 to 12 , Figure 10 Simulation waveforms provided for embodiments of this application Figure 1 , Figure 11 Simulation waveforms provided for embodiments of this application Figure 2 , Figure 12 Simulation waveforms provided for embodiments of this application Figure 3 .

[0068] Figure 10 The DC output side is 200A, the peak pulse side is 1900A, the frequency is 500Hz, and the pulse width is 40μs, as provided in the embodiments of this application. The waveform diagram is a simulation waveform at 755V. Figure 11 The DC output current provided in this embodiment remains 200A, but the peak current has been changed to 25μs, resulting in a reduction of the peak current to 1600A. Figure 12 The DC current is changed to 500A in the embodiment of this application, while the peak side parameters remain unchanged, and the final peak pulse is 1850A.

[0069] like Figure 10As shown in the figure: (a) green G_5 is the driving waveform of the peak pulse generation circuit; (b) green Iout_DC is the DC side output current waveform; red Iout_Pulse is the peak side output current waveform; yellow Iout is the DC plus peak output waveform in the mixed state; blue Iout1 is the output waveform without DC and bootstrap power supply circuit; since Iout, Iout_DC, and Iout_Pulse will partially overlap, the main focus is on observing the final output current Iout; (c) shows the circuit voltage situation, green Vout_DC is the DC side output voltage; blue Vout_Pulse is the peak side output voltage; red Vout is the total output voltage; yellow Vc is the bootstrap clamp power supply voltage; it should be noted that green Vout_DC will be obscured by red Vout.

[0070] like Figure 11 As shown in the figure: (a) green G_5 is the driving waveform of the peak pulse generation circuit; (b) green Iout_DC is the DC side output current waveform; red Iout_Pulse is the peak side output current waveform; yellow Iout is the DC plus peak output waveform in the mixed state; blue Iout1 is the output waveform without DC and bootstrap power supply circuit; since Iout, Iout_DC, and Iout_Pulse will partially overlap, the main focus is on observing the final output current Iout; (c) shows the circuit voltage situation, green Vout_DC is the DC side output voltage; blue Vout_Pulse is the peak side output voltage; red Vout is the total output voltage; yellow Vc is the bootstrap clamp power supply voltage; it should be noted that green Vout_DC will be obscured by red Vout.

[0071] like Figure 12 As shown in the figure: (a) green G_5 is the driving waveform of the peak pulse generation circuit; (b) green Iout_DC is the DC side output current waveform; red Iout_Pulse is the peak side output current waveform; yellow Iout is the DC plus peak output waveform in the mixed state; blue Iout1 is the output waveform without DC and bootstrap power supply circuit; since Iout, Iout_DC, and Iout_Pulse will partially overlap, the main focus is on observing the final output current Iout; (c) shows the circuit voltage situation, green Vout_DC is the DC side output voltage; blue Vout_Pulse is the peak side output voltage; red Vout is the total output voltage; yellow Vc is the bootstrap clamp power supply voltage; it should be noted that green Vout_DC will be obscured by red Vout.

[0072] Figures 10 to 12This is a simulation waveform diagram of the hybrid converter in this embodiment under DC plus pulse hybrid output. The corresponding main parameters include peak side current. DC side current and bootstrap clamping power supply voltage Meanwhile, the simulation parameters are designed as follows: the load is a TC4 titanium alloy with a length of 100mm, a width of 25mm, and a height of 0.5mm; the line stray current is 4μH; the DC side filter inductance is 35μH; the phase-shifted full-bridge soft-opening tube inductance is 4.5μH; the operating voltage of the phase-shifted full-bridge and pulse peak is 250V; and the transformer primary and secondary side ratio is 8:1.

[0073] like Figure 10 As shown, 20μF The voltage is 25μF, and waveform (a) in the figure shows the drive signal for the pulse output. From... Figure 10 It can be clearly seen that the pulse peak decreases 15μs faster than the rise, and it is also significantly faster than the output out1 of the original pulse generator circuit.

[0074] like Figure 11 As shown, the peak-side pulse width was changed. , , With the parameters adjusted to 25μs, 30μH, and 10μF, the peak output amplitude is now 1600A. The fall time is 7μs at 950V.

[0075] like Figure 12 The image shows a change in the DC output parameters. Adjusting it to 500A while keeping other parameters unchanged, the peak current is now 1850A. The pulse fall time remains unchanged at 7.1 μs.

[0076] based on Figures 10 to 12 We have clarified that the hybrid converter and control method for metal electroplastic treatment in this embodiment achieves at least the following technical effects:

[0077] Traditional electroplastic heating of metals often employs direct current (DC), and the current waveforms of high-energy pulse injection tests are limited or even consist of a single pulse waveform. However, the electroplasticity of metals is not a simple thermal effect; therefore, traditional waveforms cannot decouple the DC thermal and electrical effects. To address this, the hybrid converter for metal electroplastic processing in this embodiment can flexibly output a combination of DC and pulse waveforms, allowing for a more systematic exploration of the mechanisms underlying metal electroplasticity.

[0078] from Figures 10 to 12As can be seen from (b) respectively, compared with the original pulse generation circuit of Iout1 in blue, the addition of the bootstrap clamp power supply circuit in this embodiment can greatly accelerate the discharge process and make it controllable. This can reduce the thermal effect brought by the pulse, thereby highlighting the electrical effect, achieving decoupling between electricity and heat, and making the electroplasticity investigation process clearer.

[0079] Simultaneously, temperature control is achieved through a combination of DC and peak pulses. With a fixed total power, adjusting the power ratio between the DC and peak pulses amplifies the DC thermal or peak electrical effects during the electroplasticity treatment process. For example, by superimposing a peak pulse (with temperature fluctuations within acceptable limits) under stable DC temperature control, the influence of the peak electrical effect on the electroplasticity of the metal at a fixed temperature can be studied.

[0080] The following is a summary and explanation of this embodiment in conjunction with a specific application. The hybrid converter with metal electroplastic treatment proposed in this embodiment includes four parts: a phase-shifted full-bridge circuit, a rectifier and filter circuit, a pulse generator circuit, and a bootstrap clamping power supply circuit. Among them, the phase-shifted full-bridge circuit and the rectifier and filter circuit are the DC thermal effect output terminals, while the pulse generator and bootstrap clamping power supply circuit highlight the influence of the pulse electrical effect.

[0081] The DC output side consists of a full-bridge inverter circuit and a rectifier and filter circuit. The full-bridge inverter circuit uses SiC MOSFETs as switching devices and the output DC current is used as the control parameter. Precise control of the output current is achieved by adjusting the phase angle of the inverter circuit. This DC-side circuit structure can adapt to the power supply stability requirements of different pulse rise rates and can achieve constant DC output over a wide input voltage range.

[0082] The peak pulse side consists of a pulse generation circuit and a bootstrap clamping power supply circuit, with SiC MOSFETs used as the switching devices. The pulse generation circuit employs a full-bridge structure: switches 1 and 4 control the width and peak value of the pulse current; switches 2 and 3 provide a freewheeling path. With the introduction of the bootstrap clamping power supply circuit, the circuit's discharge speed is no longer limited by the voltage source, significantly improving the discharge slope, especially at lower input voltages.

[0083] Furthermore, the bootstrap clamping power supply circuit allows for adjustment of the clamping voltage by regulating the capacitor and inductor parameters, thereby controlling the discharge rate. During the pulse generation phase, energy feedback can be achieved by turning on the corresponding switching transistors to reduce losses. Simultaneously, the power supply level can be adjusted by controlling the on / off state of the switching transistors in the control circuit, thus flexibly controlling the magnitude of the clamping voltage.

[0084] Accordingly, the present invention also provides a current control output method and a coordinated temperature control method suitable for DC-DC peak pulse converters. The main implementation process of this method includes:

[0085] The current output control comprises two parts: the DC side and the peak pulse side. The DC side control uses the output current of the rectifier-filter circuit as closed-loop feedback. This feedback is compared with a set DC reference value to generate an error signal, which is then processed by a PI regulator. Finally, the DC output current is controlled by adjusting the phase shift angle of the inverter circuit. The peak pulse side employs a similar control strategy: the peak output current of the pulse generator circuit is used as feedback. After the same closed-loop regulation, the peak pulse current is adjusted by controlling the on-time of switches 1 and 4. Both parts work together to achieve a hybrid regulation of DC thermal effects and peak pulse electrical effects.

[0086] In coordinated temperature control, the output power of both the DC and peak pulse components needs to be adjusted simultaneously. For example, it is known that the thermal power required to maintain a certain metal material at 1000°C is 500W. By pre-measuring the load resistance and line inductance parameters, the corresponding output voltage can be calculated on the DC side based on the controlled output current, thus obtaining the real-time output power on the DC side. For the peak pulse side, its output power needs to be calculated separately for the current rise and fall stages: given the load resistance and inductance, the required rise pulse width can be determined based on the target peak current and input voltage; simultaneously, the fall pulse width can be determined using the reverse discharge voltage set by the bootstrap clamp power supply circuit; combined with the pulse repetition frequency, the average power of the peak pulse component can be calculated using the current square integral method. By combining the power calculation results from both the DC and pulse sides, coordinated temperature control of the metal material can be achieved.

[0087] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0088] 1. The topology proposed in this invention can flexibly output arbitrary combinations of DC and peak current waveforms, making it suitable for studying the respective effects of thermal and electrical effects in the electroplastic processing of metals. This structure can be used to study DC processing methods dominated by pure thermal effects, as well as to explore the high-energy pulse processing mechanism dominated by electrical effects, and also supports the analysis of the combined effects of the two.

[0089] 2. To overcome the pulse tailing phenomenon caused by stray line parameters and to solve the problem of turn-off time being limited by power supply voltage in traditional full-bridge pulse generation circuits, this invention introduces an improved bootstrap clamping energy feeding circuit. This circuit utilizes internally stored energy to provide a clamping voltage higher than the input voltage during the turn-off phase, thereby accelerating the turn-off process. Its effect is unaffected by the power supply voltage, and the improvement is particularly significant under low-voltage input conditions. Furthermore, this circuit can also achieve energy feedback during the pulse generation phase, helping to reduce system losses.

[0090] 3. Regarding temperature control, this invention achieves precise control of the load temperature by synergistically adjusting the combined output power of DC and pulse. Specifically, the DC side controls its output power by adjusting the phase shift angle of the inverter circuit; the pulse peak side controls the power injected by the pulse by adjusting the pulse peak value and repetition frequency. Overall temperature control must ensure that the total output power remains essentially constant, while the power distribution between the DC and pulse peak components can be dynamically and synergistically adjusted according to process requirements.

[0091] Finally, it should be noted that the above description is only a preferred embodiment of this application and is not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A hybrid transformer for metal electroplastic processing, characterized by, It includes a phase-shifted full-bridge circuit, a rectifier and filter circuit, a pulse generator circuit, and a bootstrap clamping power supply circuit; wherein: the phase-shifted full-bridge circuit is connected to the rectifier and filter circuit through a transformer, together forming the DC output side; the peak pulse side is composed of a pulse generator circuit divided into a current rising phase and a bootstrap clamping power supply circuit controlled by the falling phase. The pulse generation circuit includes a switching transistor. Switching transistor Switching transistor Switching transistor ,diode ,diode and capacitor Among them: switching transistors to Construct a full-bridge pulse generator circuit, with output diodes With capacitor The parallel connection provides energy for the pulse peak, and the output series-side diodes... This makes the output current relatively independent; The bootstrap clamping power supply circuit includes diodes. ,diode ,inductance Switching transistor and capacitor Among them: diodes ,inductance Switching transistor With capacitor Series connection, diode Parallel to inductor With switching transistor middle; The pulse peak side is equipped with corresponding control methods, including: The rising phase is when the peak current value is collected. With the set peak The difference between the magnitudes is fed into the proportional-integral module to control the switching transistor. With switching transistor The pulse width is adjusted to regulate the output peak value and capacitor voltage. This is in the switching transistor With switching transistor Adjust the switching transistor under conduction conditions The conduction time is adjusted to regulate the energy feedback amount, and to perform the following: Flexible adjustment.

2. The hybrid converter with metal electroplastic treatment according to claim 1, characterized in that, Phase-shifted full-bridge inverter circuit includes diodes ,capacitance Switching transistor Switching transistor Switching transistor Switching transistor ,capacitance ,capacitance ,capacitance ,capacitance and inductor Among them: diodes With capacitor This is the input section of the inverter circuit; the switching transistor. to A full-bridge inverter circuit is constructed, with capacitors connected in parallel on each side. to ,inductance Connected in series with the primary transformer, making the inductance The capacitor connected in parallel with the switch forms a soft switch.

3. The hybrid converter with metal electroplastic treatment according to claim 1, characterized in that, The rectifier filter circuit includes diodes. ,diode ,diode ,inductance and capacitor Among them: diodes and To form a full-wave rectifier circuit, an inductor is connected in series. and parallel capacitors A diode is connected in series at the output terminal. This makes the output current on each side relatively independent.

4. The hybrid converter with metal electroplastic treatment according to claim 1, characterized in that, Metallic materials and stray inductance, including inductance and resistance Among them: inductance and resistance It is represented by a series structure, which represents the actual load situation.

5. The hybrid converter with metal electroplastic treatment according to claim 2, characterized in that, The DC output side is equipped with corresponding control methods, including: Acquire the output current of the rectifier and filter circuit The size serves as feedback and sets the DC output size. The difference is calculated and transmitted to the preset proportional-integral module. After limiting, the dead-time, direction shift, and inversion control are applied to the four switches of the full-bridge inverter circuit. to This controls the output circuit.

6. A method for coordinated temperature control of a metal electroplastic treatment hybrid converter, using the metal electroplastic treatment hybrid converter as described in any one of claims 1-5, characterized in that, The hybrid converter is equipped with corresponding collaborative temperature control methods, including: DC side by collecting output current As a feedback control variable, the DC power is calculated in conjunction with the load parameters; the power calculation on the peak pulse side is performed separately for the rising and falling phases to obtain the peak pulse power. The total power is the sum of the DC power and the peak pulse power; In total power control, when a peak pulse power is applied, the DC power needs to be adjusted accordingly to stabilize the total power at the set value. DC power is adjusted by controlling the phase angle of the phase-shifted full-bridge circuit; peak pulse power is adjusted by changing the pulse frequency or adjusting the falling platform voltage to control the rate of current decrease.

7. The synergistic temperature control method for a hybrid converter with metal electroplastic treatment according to claim 6, characterized in that, The calculation process for peak pulse power involves obtaining the average power of this part by using the current square integral method based on circuit inductance, input voltage, falling plateau voltage, set peak current, and pulse frequency.

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