Triple degaussing and heating integrated power supply

Abstract

A triple degaussing and heating integrated power supply is applied to the field of pipeline heating and degaussing and is composed of a main circuit, a strong magnetic degaussing control circuit, a direct current degaussing control circuit, an alternating current preheating control circuit and output coils, and the main circuit, the strong magnetic degaussing control circuit, the direct current degaussing control circuit and the alternating current preheating control circuit share at least one output coil. The output coil is composed of a plurality of strands of enameled wires or steel wires, it is ensured that the workpieces are demagnetized while being heated, and the workpieces are welded in real time.

Description

Technical Field

[0001] The utility model relates to a power supply used for pipeline demagnetization, in particular to an integrated power supply which can perform functions such as demagnetization and heating while performing heat treatment and welding on the pipeline. Background Art

[0002] When repairing and welding oil pipelines, generally speaking, since the oil pipelines are used underground for a long time, they will be affected by the geomagnetic field and magnetized. Since the pipelines are too long, the magnetism will be very strong. When the pipelines need to be repaired, arc welding is used for welding, which is affected by the magnetic field, resulting in welding deviations and affecting the welding quality. Therefore, it is necessary to demagnetize the pipeline before welding. In order to improve the welding quality, the pipeline needs to be preheated during welding, otherwise cold welding will cause cracks in the weld. In this way, the repaired pipeline must be preheated before welding, and it also needs to be demagnetized in advance.

[0003] In traditional technology, for various workpieces with residual magnetism that need to be welded at the same time as heat treatment, the workpiece is generally demagnetized and preheated before welding. After the preheating work is completed, welding can be carried out, which is inefficient and the temperature cannot be ensured during welding. Because the traditional operation process is: first measure the residual magnetism of the workpiece, first wrap the demagnetization cable of the demagnetizer, demagnetize the workpiece with the demagnetizer according to the residual magnetism, and then measure again. After the residual magnetism is basically zero, remove the wound demagnetization cable of the demagnetizer, and then wrap the workpiece with the electromagnetic induction heating cable, and then start heating the workpiece. In this process, for super long workpieces, the magnetic field of other parts will magnetize the workpiece of the welding part again. After the heating temperature reaches the requirement, when welding starts, if the magnetization is too fast and too strong, it will seriously affect the welding quality, and demagnetization may be required again. Therefore, the staff needs to complete the entire process by winding the cable at least twice, and the welding quality may not be guaranteed.

[0004] This brings a complicated process flow to the traditional operation process, which requires multiple winding, connection and replacement of the workpiece, and requires the use of at least two sets of different equipment, which has high requirements for the on-site environment and greatly increases the cost of the overall equipment. And the welding quality is still not necessarily guaranteed.

[0005] In traditional technology, no other equipment or devices have been seen to be used in the above-mentioned occasions to improve the relevant efficiency and quality, and to improve the relevant existing process to achieve higher accuracy and economy.

[0006] In some technical means similar to the present application, such as the invention patent application in China (name: A low-frequency demagnetization power supply for electric transformer, publication number: CN109889055A), a low-frequency demagnetization circuit of a certain structure with only a single function is provided, and it must be used in conjunction with a transformer. It is not feasible to apply it directly or based on relevant principles to the technical occasions of the present application. Utility Model Content

[0007] In view of the above-mentioned deficiencies in the prior art, the utility model provides a triple demagnetization and heating integrated power supply to solve at least one of the above-mentioned technical problems.

[0008] The technical solution of this utility model is as follows:

[0009] A triple demagnetization and heating integrated power supply consists of a main circuit, a strong magnetic demagnetization control circuit, a DC demagnetization control circuit, an AC preheating control circuit and an output coil. The main circuit, the strong magnetic demagnetization control circuit, the DC demagnetization control circuit and the AC preheating control circuit share at least one output coil, and the output coil is made of multiple strands of enameled wire or Lisi wire.

[0010] Preferably, in the main circuit, the three-phase input circuit is connected to the terminal block UVWNE, and then the rear end of the terminal block UVWNE is connected to the input end of the circuit breaker K1, the output end of the circuit breaker K1 is connected to the AC side of the rectifier circuit BR0, and the non-inductive capacitor Ci is connected in parallel to the two ends of the DC side of the rectifier circuit BR0; the positive electrode of the rectifier circuit BR0 is connected to one end of the main contact of the AC contactor K2, and the other side of the main contact of the AC contactor K2 is connected to the negative electrode of the diode D0; the positive electrode of the diode D0 is connected to one end of the reactance L0, and the other end of the reactance L0 is connected to the positive electrode of the rectifier circuit BR0; the positive electrode of the diode D0 is connected to the source of the half-bridge insulated gate bipolar transistor (D1) The cathode of the diode D0 is respectively connected to one end of the capacitor Cg and the capacitor Ch, the positive ends of the inverter group DR1 and the inverter group DR2, and one end of the first contact of the output relay K3; the drain of the half-bridge insulated gate bipolar transistor (D1) is respectively connected to the negative electrode of the rectifier circuit BR0, the other end of the capacitor Cg and the capacitor Ch, the negative ends of the inverter group DR1 and the inverter group DR2, and one end of the second contact of the output relay K3; one end of the filter capacitor group C0 is connected to one side of the circuit breaker K1, and the other end is connected to the negative end of the rectifier circuit BR0; one end of the resistor R is connected to one end of the filter capacitor group C0, and the other end is connected to the negative end of the rectifier circuit BR0.

[0011] Preferably, the terminal row consists of 3-phase 4-wire U, V, W and E, or 3-phase 5-wire U, V, W, N and E; the rectifier circuit BR0 consists of at least 3 half-bridge rectifier modules and a non-inductive capacitor Ci.

[0012] Preferably, the strong magnetic demagnetization control circuit includes a three-phase input circuit, a boost circuit, a rectifier circuit BR0, a filter circuit, a discharge circuit, an output relay K3 and an output coil circuit, wherein the three-phase input circuit is composed of 3-phase 4-wire U, V, W and E, or 3-phase 5-wire U, V, W, N and E, and is input into the rectifier circuit BR0 through the circuit breaker K1, and then connected to the non-inductive capacitor Ci; the rectifier circuit BR0 is composed of at least 3 half-bridge rectifier modules and a non-inductive capacitor Ci; the filter circuit adopts a large-capacitance filter capacitor group C0, the discharge circuit is composed of a resistor R, and the other end of the first contact of the output relay K3 and the other end of the second contact are respectively connected to the two ends of the output coil.

[0013] Preferably, the boost circuit is a BOOST circuit DR0 composed of a half-bridge insulated gate bipolar transistor (D1), an inductor L0 and a diode D0, wherein the boost drive signal of the half-bridge insulated gate bipolar transistor (D1) is controlled by the control board output control signal, and when the output boost voltage reaches the required value, the output control is stopped.

[0014] Preferably, the DC demagnetization control circuit is composed of a capacitor Ch, an inverter group DR1, a DC isolation capacitor C1, a transformer TR1, and a rectifier circuit BR1, wherein one output end of the inverter group DR1 is connected to one end of the DC isolation capacitor C1, the other output end of the inverter group DR1 is connected to one end of the primary side of the transformer TR1, and the other end of the primary side of the transformer TR1 is connected to the other end of the DC isolation capacitor C1. One end of the secondary side of the transformer TR1 is connected to one end of the input of the rectifier circuit BR1, and the other end of the secondary side of the transformer TR1 is connected to the other end of the input of the rectifier circuit BR1; the positive and negative poles of the rectifier circuit BR1 are respectively connected to the two ends of the output coil.

[0015] Preferably, the inverter group DR1 is a bridge inverter topology circuit, which is composed of two full-bridge insulated gate bipolar transistor IGBT modules.

[0016] Preferably, the rectifier circuit BR1 is composed of four diodes or two half-bridge IGBT modules.

[0017] Preferably, the AC preheating control circuit is composed of a capacitor Cg, an inverter group DR2, a capacitor C2, a transformer TR2, and impedance matching capacitors C3 and C4, wherein one output end of the inverter group DR2 is connected to one end of the capacitor C2, the other output end of the inverter group DR2 is connected to one end of the primary side of the transformer TR2, and the other end of the primary side of the transformer TR2 is connected to the other end of the capacitor C2. One end of the secondary side of the transformer TR2 is connected to one end of the capacitor C3, the other end of the secondary side of the transformer TR2 is connected to one end of the capacitor C4, and the other end of the capacitor C3 and the other end of the capacitor C4 are respectively connected to the two ends of the output coil.

[0018] Preferably, the inverter group DR2 is a bridge inverter topology circuit, and its control signal is connected to the output terminal of the drive board of the control board. The inverter group DR2 is composed of four half-bridge IGBTs or two full-bridge IGBT modules.

[0019] The beneficial effects of the utility model compared with the prior art are as follows:

[0020] The technical solution of the utility model can be applied to pipelines, especially on extra-long steel pipes or solid steel workpieces. After high-voltage DC pulse demagnetization is used to remove most of the retained magnetic field, low-voltage DC is continued to be used to eliminate the remaining magnetism, so that welding can be performed while electromagnetic induction heating is performed. The utility model is particularly suitable for pipeline repair in petrochemical industry, and repair can be performed simultaneously without affecting the application of the pipeline, thereby improving efficiency.

[0021] The utility model relates to an integrated power supply with the integrated functions of strong magnetic demagnetization + direct current demagnetization + alternating current heating demagnetization, which is composed of a main circuit, a strong magnetic demagnetization control circuit, a direct current demagnetization control circuit, an alternating current preheating control circuit and an output coil, so that pulse demagnetization, direct current demagnetization and electromagnetic induction heating circuits can share an output coil. In this scheme, direct current demagnetization, alternating current demagnetization and electromagnetic induction heating share the coil wound by the same output cable, and the overall function is continuously realized in one, and there is no need to manually reconnect and switch according to the function. When the power supply is working, the automatic working mode is selected. After power is turned on, the direct current boost will be performed first. When the voltage reaches the requirement, the relay will be automatically connected, and pulse high-voltage demagnetization will be performed instantly. The demagnetization current can reach thousands of amperes, and the demagnetization time is milliseconds. The pulse demagnetization is completed quickly; then the direct current low-voltage continuous demagnetization, alternating current demagnetization and electromagnetic induction heating are started together. During the direct current low-voltage demagnetization, a direct current of hundreds of amperes is continuously output for demagnetization, and the alternating current output by electromagnetic induction is simultaneously used for alternating current demagnetization, and the electromagnetic induction principle is used to heat the workpiece with electromagnetic induction. That is, direct current demagnetization, alternating current demagnetization and electromagnetic induction heating share a demagnetization and heating coil composed of an output cable. The present application integrates direct current pulse demagnetization, direct current demagnetization and alternating current demagnetization into the electromagnetic induction heating power supply. While heating the workpiece that needs to be heat treated, the workpiece with an ultra-strong magnetic field can be demagnetized, ensuring that demagnetization is performed while heating, so that the workpiece can be welded in real time. The parameters of the electromagnetic induction heating output current, high-voltage pulse demagnetization intensity and low-voltage direct current demagnetization current are continuously adjustable, and the entire heating and demagnetization process can be completed automatically and overcomes many defects in traditional technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a circuit structure diagram of the utility model.

[0023] Figure 2It is a circuit schematic diagram of the auxiliary control board and the driving part of the utility model.

[0024] Figure 3 It is a schematic diagram of the strong magnetic demagnetization working circuit of the utility model.

[0025] Figure 4 It is a schematic diagram of the DC demagnetization working circuit of the utility model.

[0026] Figure 5 It is a schematic diagram of an AC preheating control circuit of the utility model.

[0027] Figure 6 The utility model is a schematic diagram of a circuit for simultaneously operating DC demagnetization and AC preheating control. DETAILED DESCRIPTION

[0028] The present invention is described in detail below with reference to the accompanying drawings and embodiments. Examples of embodiments of the present invention are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar components or components having the same or similar functions. In addition, if the detailed description of the known technology is unnecessary for the features of the present application shown, it will be omitted. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be interpreted as limiting the present invention.

[0029] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein, including technical terms and scientific terms, etc., have the same meaning as the general understanding of ordinary technicians in the field to which the utility model belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as here.

[0030] Those skilled in the art will appreciate that, unless expressly stated, the singular forms "one", "said", and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present utility model refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof. It should be understood that when we refer to an element as being "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or there may be an intermediate element. In addition, the "connection" or "coupling" used herein may include wireless connection or wireless coupling or other forms of connection. The term "and / or" used herein includes all or any unit and all combinations of one or more associated listed items.

[0031] The integrated power supply and its circuit of the present application are further described below in conjunction with specific implementation cases. It should be understood that these embodiments are only used to illustrate the present application and are not limited to the scope of the present application. At the same time, according to the specific application scenarios, relevant application technicians can make various necessary fine-tuning or modifications to the present application. These equivalent forms will not change the overall structure of the power supply, and therefore also fall within the scope defined by the claims attached to the present application.

[0032] The circuit structure of the utility model is as follows Figure 1 As shown, the external three-phase 380VAC power supply is connected to the terminal block UVWNE, and then the rear end of the terminal block is connected to the input end of the circuit breaker K1, the output end of K1 is connected to the AC side of the rectifier circuit BR0 (composed of 3 half-bridge rectifier modules), and the non-inductive capacitor Ci is connected in parallel to both ends of the DC side of BR0. The positive pole of the rectifier circuit BR0 is connected to one end of the main contact of the AC contactor K2, and the other side of the main contact of K2 is connected to the negative pole of the diode D0. The positive pole of D0 is connected to one end of the reactor L0, and the other end of L0 is connected to the positive pole of the rectifier circuit BR0. The positive pole of the diode D0 is also connected to the source of the inverter group DRO, and the drain of DRO is connected to the negative pole of the rectifier circuit BR0. One end of the filter capacitor group C0 is connected to one side of the AC contactor K2, and the other end is connected to the negative end of the rectifier bridge BR0. One end of the resistor R is connected to one end of the capacitor group C0, and the other end is connected to the negative end of the rectifier circuit BR0. The cathode of diode D0 is also connected to one end of capacitor Cg, one end of capacitor Ch, the positive end of inverter group DR1, the positive end of inverter group DR2 and one end of the first contact of AC contactor K3, and the drain of half-bridge insulated gate bipolar transistor D1 is also connected to the other end of capacitor Cg, the other end of capacitor Ch, the negative end of inverter group DR1, the negative end of inverter group DR2 and one end of the second contact of AC contactor K3. The other end of the first contact of AC contactor K3 and the other end of the second contact are respectively connected to the two ends of the output coil. One output end of inverter group DR1 is connected to one end of capacitor C1, and the other output end of inverter group DR1 is connected to one end of the primary side of transformer TR1, and the other end of the primary side of transformer TR1 is connected to the other end of capacitor C1. One end of the secondary side of transformer TR1 is connected to one end of the input of rectifier circuit BR1, and the other end of the secondary side is connected to the other end of the input of rectifier circuit BR1. The positive and negative electrodes of rectifier circuit BR1 are respectively connected to the two ends of load COIL. One output end of the inverter group DR2 is connected to one end of the capacitor C2, and the other output end of the inverter group DR2 is connected to one end of the primary side of the transformer TR2, and the other end of the primary side of TR2 is connected to the other end of the capacitor C2. One end of the secondary side of the transformer TR2 is connected to one end of the capacitor C3, and the other end of the secondary side is connected to one end of the capacitor C4. The other end of the capacitor C3 and the other end of the capacitor C4 are respectively connected to the two ends of the load COIL.

[0033] The integrated power supply with triple demagnetization and heating functions disclosed in the embodiment of the utility model (having the integrated functions of strong magnetic demagnetization + low voltage demagnetization + AC heating demagnetization) includes a common main circuit and a DC boost circuit, a DC pulse demagnetization circuit, a DC low voltage continuous demagnetization circuit and an electromagnetic induction heating circuit. At the same time, the pulse demagnetization, DC demagnetization, AC demagnetization and electromagnetic induction heating circuits share an output coil induction heating circuit and a demagnetization circuit, and the induction heating circuit and the demagnetization circuit share a coil. The main circuit circuit is as follows Figure 1 As shown, the three-phase 380VAC power supply enters the circuit breaker K1, and is connected to the rectifier circuit BR0 (composed of 3 half-bridge rectifier modules) by K1. At the same time, the Ci non-inductive capacitor is connected after rectification to prevent external high-frequency signals from being input into this power supply. At the same time, it can also prevent the high-frequency signal output of this power supply from interfering with the grid power supply, playing a role in shielding a high-frequency circuit. When the AC contactor K2 is not closed, the rectified DC current can be blocked by the reactance L0 and then enter the capacitor filter group. When high-voltage pulse demagnetization is required, the BOOST of the control board outputs a PWM signal. See Figure 2 As shown, after the PWM signal of BOOST is output by DSP, it is connected to the driver board 1, and then connected to the G pole of the IGBT in the BOOST circuit through the driver board 1, the input voltage is boosted to a certain voltage value, and then under the high-intensity magnetic field, this voltage needs to be increased to about 800V DC (for example, between 780V and 880V), after high-voltage pulse demagnetization (for example: when the boosted DC voltage is 800V, the short-term output current can reach about 2000-3000A, depending on the size of the wound coil inductance), the voltage is reduced to about the normal rectifier voltage, and then the control board outputs a control signal to close the AC contactor K2, providing a DC bus voltage circuit for subsequent low-voltage DC demagnetization and AC induction heating. The filtering of the DC filter capacitor group provides the output of the DC low-voltage demagnetization inverter circuit, and also provides the induction heating inverter output. After power failure, for safety, the voltage on the filter capacitor will be released through the discharge circuit R.

[0034] The DC degaussing control circuit is mainly composed of capacitor Ch, inverter group DR1, DC isolation capacitor C1, transformer TR1, rectifier circuit BR1, etc. Figure 1 As shown in the box of part A in the figure. The inverter group DR1 full-bridge phase-shift inverter topology consists of two half-bridge IGBT (half-bridge insulated gate bipolar transistor) modules, and the four-way control signals are controlled by the control board (see Figure 2) outputs a DC demagnetization PWM signal, and after passing through the driver board 2, it is provided to the G poles of the four IGBTs to achieve the purpose of control. The DC demagnetization adopts a bridge phase-shifted resonant soft switching control strategy. After isolation by the transformer TR1, it is output to the rectifier circuit BR1, which is composed of two half-bridge diode modules. The DC voltage range output to the coil is from 0 to 60V, and the output current range is from 0 to 800A.

[0035] The AC preheating control working circuit is mainly composed of capacitor Cg, inverter group DR2, capacitor C2, transformer TR2 and impedance matching capacitors C3 and C4. The inverter group DR2 is composed of four half-bridge insulated gate bipolar transistors IGBT. Figure 1 The DR2 full-bridge phase-shift inverter topology consists of two half-bridge IGBT modules, and the four-way control signals are controlled by the control board (see Figure 2 ) outputs the induction heating PWM signal, and after passing through the driving board 3, it is provided to the G poles of the four IGBTs to achieve the purpose of control. The induction heating adopts the bridge phase-shift resonance and frequency automatic tracking control strategy. After the impedance transformation and isolation of the transformer TR2, it is output to the capacitors C3 and C4 and forms a resonant induction circuit with the output coil. The resonant frequency is a series resonant circuit composed of the inductance L of the output coil and the capacitors C3 and C4. C3 and C4 are selected as different impedance matching capacitors according to the electromagnetic induction effect of the material of the heated workpiece. Generally, the operating frequency of induction heating is basically set within 5-20KHz, that is, locked in the medium frequency range.

[0036] The final output is directly applied to the workpiece through the coil. For the user, as long as the output coil is wound around the workpiece and the residual magnetic field strength on the workpiece is measured, the relevant high-voltage pulse demagnetization voltage value can be set according to the size of the magnetic field. Alternatively, high-voltage pulse demagnetization is not required and only DC low voltage is used for demagnetization. Alternatively, since there is no residual magnetism, DC demagnetization is not required at all and heat treatment can be directly performed while welding can be performed directly. The operation is simple and convenient, and these process operations can be set directly through the human-computer interaction control interface of the power supply.

[0037] Therefore, the technical solution provided by the present application not only saves manpower and material resources, but also reduces the cost of equipment, simplifies the operation process, improves efficiency, and improves the quality of heat treatment and welding. At the same time, the utility model also provides a new circuit structure design for use in related occasions and reduces the cost and energy consumption.

[0038] The working process and application mode of the present application may be as follows in some embodiments:

[0039] First use a measuring instrument to measure the size and direction of the magnetic field on the pipeline. After determining the polarity of the demagnetization, connect the direction of the demagnetization coil to the corresponding output terminal of the power supply as required.

[0040] First, the strong magnetic demagnetization function is performed, that is, the high voltage instantaneous demagnetization function. The overall structure of the power supply is shown in Figure 3 As shown. The circuit consists of a three-phase input circuit, a rectifier circuit, a filter circuit, a discharge circuit and an output coil circuit. The three-phase input circuit consists of 3-phase 4-wire (U, V, W and E), or 3-phase 5-wire (U, V, W, N and E), and is input into the rectifier circuit through the circuit breaker K1. The rectifier circuit consists of BR0 (3 half-bridge rectifier modules) and Ci, that is, the Ci non-inductive capacitor is connected after rectification. The input rectified voltage is sent to the boost circuit as shown in Figure 3 A BOOST circuit DR0 composed of a half-bridge insulated gate bipolar transistor (D1), a reactor L0 and a diode D0 is boosted by a boost circuit, and the boosted voltage reaches a DC voltage of about 800V. The filter circuit adopts a large capacitor filter C0 capacitor group. The discharge circuit is composed of R. The output coil circuit is composed of a coil. When the voltage is boosted to 800V (it can also be controlled to a certain value between 780V and 880V, for example), the controller outputs a high-voltage demagnetization control signal, and the output relay K3 is attracted, and the DC output of the coil is completed instantly, forming the first demagnetization circuit, that is, high-voltage DC pulse demagnetization. After the demagnetization is completed, this part of the circuit no longer works.

[0041] Secondly, DC low-voltage continuous demagnetization and AC induction heating can be carried out simultaneously, such as Figure 6 As shown. The independent working process of DC low voltage continuous demagnetization and AC induction heating is as follows:

[0042] DC low voltage continuous degaussing circuit Figure 4The circuit includes a three-phase input circuit, a rectifier circuit, a filter circuit, a discharge circuit, a DC low-voltage control circuit and an output coil circuit. The three-phase input circuit consists of 3 phases and 4 wires (U, V, W and E), or 3 phases and 5 wires (U, V, W, N and E), and is input into the rectifier circuit through the circuit breaker K1. The rectifier circuit consists of BR0 (composed of 3 half-bridge rectifier modules) and Ci, that is, the Ci non-inductive capacitor is connected after rectification. The filter circuit adopts a large capacitor filter C0 capacitor group. The discharge circuit is composed of R. The output coil circuit is composed of COIL. The control part of the low-voltage continuous demagnetization is composed of capacitor Ch, inverter group DR1, DC isolation capacitor C1, transformer TR1, and rectifier circuit BR1. DR1 is composed of four IGBTs (insulated gate bipolar transistors), and can also be composed of two full-bridge IGBT modules. The control signal is output by the control board and provided to the G poles of the four IGBTs after passing through the driver board. The controller output adopts a bridge phase-shifted resonant soft switching control strategy. After being isolated by transformer TR1, the output is sent to the rectifier circuit BR1, which is composed of 4 diodes or 2 half-bridge diode modules. It uses passive rectification technology to output DC voltage, which is connected to the output coil to form a DC current magnetic field. The purpose of this part is to further offset the low weak magnetic field after high-voltage pulse demagnetization. The output current is relatively small and the output voltage is also relatively low.

[0043] AC induction heating circuit Figure 5 The three-phase input circuit is composed of 3-phase 4-wire (U, V, W and E), or 3-phase 5-wire (U, V, W, N and E), and is input into the rectifier circuit through the circuit breaker K1. The rectifier circuit is composed of BR0 (composed of 3 half-bridge rectifier modules) and Ci, that is, the Ci non-inductive capacitor is connected after rectification. The filter circuit adopts a large capacitor filter C0 capacitor group. The discharge circuit is composed of R. The output coil circuit is composed of COIL. The AC induction heating control part is composed of capacitor Cg, inverter group DR2, capacitor C2, transformer TR2 and impedance matching capacitors C3 and C4. Among them, the inverter group DR2 is composed of four half-bridge IGBTs (insulated gate bipolar transistors), and can also be composed of two full-bridge IGBTs (insulated gate bipolar transistors) modules. The control signal is output by the control board and provided to the G poles of the four IGBTs (insulated gate bipolar transistors) after passing through the driver board. The controller output adopts a bridge phase-shifted resonance real-time frequency locking control strategy. After the impedance transformation and isolation of transformer TR2, it is output to the output coil through capacitors C3 and C4. At the same time, the output AC signal frequency is composed of the series resonant circuit composed of the inductance L of the output coil and C3C4. This part heats the workpiece through the electromagnetic induction principle of AC, using the hysteresis thermal effect and skin effect theory.

[0044] The present application may have the following characteristics and effects in some specific application scenarios: 1. The electromagnetic induction heating power supply is embedded in a triple demagnetization circuit: The present application adds a triple demagnetization circuit on the basis of the conventional electromagnetic induction heating power supply. In order to meet the needs of the ultra-strong DC magnetic field, a high-voltage DC pulse demagnetization function is provided. The retained strong magnetic field is first weakened, and then demagnetized again by low-voltage DC demagnetization, so as to avoid the DC magnetic field in other parts of the workpiece magnetizing the weakened magnetic field. The demagnetization function is performed according to the strength of the retained magnetic field contained in the workpiece, so the present device has a continuously adjustable demagnetization current, which can be completed by operating on the touch screen. At the same time, during the operation of the equipment, the pulse demagnetization, DC low-voltage demagnetization, AC demagnetization and induction heating processes are all automatic. 2. Sharing of induction heating and demagnetization circuits: The present application can realize different functional requirements on the same set of shared main circuits at the same time, changing the simple combination of the demagnetizer circuit and the electromagnetic induction circuit that only integrates the demagnetizer circuit and the electromagnetic induction circuit into one machine that already exists on the market. The present device does not require an internal switching circuit, which further reduces the cost of the power supply and improves the reliability of the power supply. 3. Remote control: This application is that when the integrated power supply with triple demagnetization and heating functions is used in the field, it can be directly controlled at the workpiece site far away from the power supply. There are two types of control: wired connection control box control and wireless control box control. 4. Meet the needs of ultra-low temperature environment: This application is that the integrated power supply with triple demagnetization and heating functions can still operate normally when the ambient temperature is as low as -40°C, which is very suitable for use in ultra-low temperature environments in the field. 5. High-brightness field-specific OLED screen: This application is that demagnetization and electromagnetic induction share an OLED screen to meet the operation under strong light in the field. 6. Integrated full air cooling structure: This application is that the cooling method of the overall power supply adopts an integrated full air cooling structure, which is particularly suitable for field operations. 7. Multiple communication control: This application is to adopt multiple communication methods, with a remote wireless mode for simple connection and use, and also has a hardware interface mode using wired and optical fiber communication. The communication protocol supports Ethernet TCP / IP and wireless WIFI Modbus, and supports basic customizable RS485 and RS232 user communication protocols, etc. 8. Dual-core control mode: It consists of ARM for human-computer interaction and DSP for control output, with high-frequency, accurate and reliable ZCS and ZVS control strategies. It also has multiple heating working modes and a full range of protections. 9. Optimal working point of induction heating: It has the function of automatic tracking of the resonant frequency and phase of induction heating, ensuring that the IGBT works at the optimal working point of ZVS and ZCS in real time, and will not readjust the power supply parameters due to changes in the winding cable.

[0045] The above is only a preferred embodiment of the utility model, and does not impose any form of limitation on the method steps or structure of the utility model. Any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the utility model are within the scope of the technical solution of the utility model.

Claims

1. A triple degaussing and heating integrated power supply, characterized in that: The utility model is composed of a main circuit, a strong magnetic demagnetization control circuit, a DC demagnetization control circuit, an AC preheating control circuit and an output coil. The main circuit, the strong magnetic demagnetization control circuit, the DC demagnetization control circuit and the AC preheating control circuit share at least one output coil, and the output coil is composed of multiple strands of enameled wire or Lisi wire.

2. A triple degaussing and heating integrated power supply according to claim 1, characterized in that: In the main circuit, the three-phase input circuit is connected to the terminal block (UVWNE), and then the rear end of the terminal block (UVWNE) is connected to the input end of the circuit breaker (K1), the output end of the circuit breaker (K1) is connected to the AC side of the rectifier circuit (BR0), and the non-inductive capacitor (Ci) is connected in parallel to the two ends of the DC side of the rectifier circuit (BR0); the positive electrode of the rectifier circuit (BR0) is connected to one end of the main contact of the AC contactor (K2), and the other side of the main contact of the AC contactor (K2) is connected to the negative electrode of the diode (D0); the positive electrode of the diode (D0) is connected to one end of the reactance (L0), and the other end of the reactance (L0) is connected to the positive electrode of the rectifier circuit (BR0); the positive electrode of the diode (D0) is connected to the source of the half-bridge insulated gate bipolar transistor (D1), and the diode (D0) is connected to the source of the half-bridge insulated gate bipolar transistor (D1). The negative electrode of the diode (D0) is respectively connected to one end of the capacitor (Cg) and the capacitor (Ch), the positive ends of the inverter group (DR1) and the inverter group (DR2), and one end of the first contact of the output relay (K3); the drain of the half-bridge insulated gate bipolar transistor (D1) is respectively connected to the negative electrode of the rectifier circuit (BR0), the other end of the capacitor (Cg) and the capacitor (Ch), the negative ends of the inverter group (DR1) and the inverter group (DR2), and one end of the second contact of the output relay (K3); one end of the filter capacitor group (C0) is connected to one side of the circuit breaker (K1), and the other end is connected to the negative end of the rectifier circuit (BR0); one end of the resistor (R) is connected to one end of the filter capacitor group (C0), and the other end is connected to the negative end of the rectifier circuit (BR0).

3. A triple degaussing and heating integrated power supply according to claim 2, characterized in that: The terminal block is composed of 3-phase 4-wire (U, V, W and E), or 3-phase 5-wire (U, V, W, N and E); the rectifier circuit (BR0) is composed of at least 3 half-bridge rectifier modules and a non-inductive capacitor (Ci).

4. A triple degaussing and heating integrated power supply according to claim 1, characterized in that: The strong magnetic demagnetization control circuit comprises a three-phase input circuit, a boost circuit, a rectifier circuit (BR0), a filter circuit, a discharge circuit, an output relay (K3) and an output coil circuit, wherein the three-phase input circuit consists of three-phase four-wire (U, V, W and E) or three-phase five-wire (U, V, W, N and E), and is input into the rectifier circuit (BR0) through a circuit breaker (K1), and then connected to a non-inductive capacitor (Ci); the rectifier circuit (BR0) consists of at least three half-bridge rectifier modules and a non-inductive capacitor (Ci); the filter circuit is composed of a large-capacitance filter capacitor group (C0), the discharge circuit consists of a resistor (R), and the other end of the first contact of the output relay (K3) and the other end of the second contact are respectively connected to the two ends of the output coil.

5. A triple degaussing and heating integrated power supply according to claim 4, characterized in that: The boost circuit is a BOOST circuit DR0 composed of a half-bridge insulated gate bipolar transistor (D1), a reactance (L0) and a diode (D0), wherein the boost drive signal of the half-bridge insulated gate bipolar transistor (D1) is controlled by the control signal output by the control board, and when the output boost voltage reaches the required value, the output control is stopped.

6. A triple degaussing and heating integrated power supply according to claim 1, characterized in that: The DC demagnetization control circuit is composed of a capacitor (Ch), an inverter group (DR1), a DC isolation capacitor (C1), a transformer (TR1), and a rectifier circuit (BR1), wherein one output end of the inverter group (DR1) is connected to one end of the DC isolation capacitor (C1), the other output end of the inverter group (DR1) is connected to one end of the primary side of the transformer (TR1), the other end of the primary side of the transformer (TR1) is connected to the other end of the DC isolation capacitor (C1), one end of the secondary side of the transformer (TR1) is connected to one end of the input of the rectifier circuit (BR1), and the other end of the secondary side of the transformer (TR1) is connected to the other end of the input of the rectifier circuit (BR1); the positive pole and the negative pole of the rectifier circuit (BR1) are respectively connected to the two ends of the output coil.

7. A triple degaussing and heating integrated power supply according to claim 6, characterized in that: The inverter group (DR1) is a bridge inverter topology circuit, which is composed of two full-bridge insulated gate bipolar transistor (IGBT) modules.

8. A triple degaussing and heating integrated power supply according to claim 6, characterized in that: The rectifier circuit (BR1) consists of four diodes or two half-bridge IGBT modules.

9. A triple degaussing and heating integrated power supply according to claim 1, characterized in that: The AC preheating control circuit is composed of a capacitor (Cg), an inverter group (DR2), a capacitor (C2), a transformer (TR2) and impedance matching capacitors (C3, C4), wherein one output end of the inverter group (DR2) is connected to one end of the capacitor (C2), the other output end of the inverter group (DR2) is connected to one end of the primary side of the transformer (TR2), the other end of the primary side of the transformer (TR2) is connected to the other end of the capacitor (C2), one end of the secondary side of the transformer (TR2) is connected to one end of the capacitor (C3), the other end of the secondary side of the transformer (TR2) is connected to one end of the capacitor (C4), and the other end of the capacitor (C3) and the other end of the capacitor (C4) are respectively connected to the two ends of the output coil.

10. A triple degaussing and heating integrated power supply according to claim 9, characterized in that: The inverter group (DR2) is a bridge inverter topology circuit, and its control signal is connected to the output end of the driver board of the control board. The inverter group (DR2) is composed of four half-bridge IGBTs or two full-bridge IGBT modules.

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