A coating power supply circuit

Abstract

The present invention relates to the technical field of magnetron sputtering power supply, and in particular to a coating power supply circuit, wherein a power switch is connected in series between an output end of a power supply unit and an output end of a power supply, and when an arc is detected, the power supply output is quickly shut down by disconnecting the power switch; a line inductance is respectively connected in series to the power supply output end and the power supply output end, and the line inductance can absorb arc energy, suppress arc energy in the circuit, and protect the power supply; a first freewheeling branch is connected in parallel to the output end of the power supply unit, and a second freewheeling branch is connected in parallel to the output end of the power supply, the first freewheeling branch and the power supply unit and the line inductance connected in series form a first energy absorption circuit, the second freewheeling branch and the power supply output end and the line inductance connected in series form a second energy absorption circuit, and network loops on both sides of the power switch absorb energy synchronously, can quickly absorb the energy stored in a filter loop inside the power supply and the line inductance, achieve rapid arc extinguishing, and ensure the safety and stability of the power supply.

Description

Technical Field

[0001] The invention relates to the technical field of magnetron sputtering power supply, and in particular to a coating power supply circuit. Background Art

[0002] In the vacuum magnetron sputtering coating process, arcing usually occurs in the vacuum chamber where the coating occurs due to poor coating material quality and unreasonable sputtering power settings. When the arc occurs, the current in the circuit increases abnormally, often several times the normal working current, and the power supply is close to a short circuit state, seriously affecting the safety of components in the internal circuit of the power supply. With the continuous development of coating technology, higher requirements are put forward for the speed of arc extinguishing and whether the arc extinguishing is thorough.

[0003] At present, energy storage elements are usually added to the power supply circuit to absorb arc energy and suppress the arc. For example, capacitor elements are added inside the power supply, and the capacitor charges to absorb the arc energy in the circuit, or a large-capacity inductor is connected in series in the power supply circuit to absorb energy to suppress the impact of arc current on the power supply. However, at the moment the power is disconnected, the capacitor or inductor releases energy, which will produce a stronger arc, threatening the safety of the power supply, and the arcing phenomenon will become more frequent. The coating can hardly be carried out normally, and the coating quality is greatly affected.

[0004] In the prior art, some circuits add energy-consuming elements to the arc suppression circuit to consume energy, but most of the arc suppression circuits or arc absorption circuits have only one, which requires periodic cycle consumption, and it is difficult to meet the demand for efficient and thorough arc extinguishing of the power supply.

[0005] Based on the problems in the prior art, the present invention provides a coating power supply circuit. Summary of the invention

[0006] The purpose of the present invention is to provide a film-coated power supply circuit to solve the technical problems in the prior art that the arc extinguishing circuit of the power supply is not efficient and the arc extinguishing effect is not thorough.

[0007] The technical solution of the present invention is: a coating power supply circuit, comprising a power supply unit, a first line inductance group is connected in series to the output end of the power supply unit, a first freewheeling branch and a second freewheeling branch are connected in parallel between the output end of the power supply unit and the power supply output end, a power switch is connected in series on the main road connecting the output end of the power supply unit to the power supply output end; the power supply output end is connected to a load through the second line inductance group in series;

[0008] The first freewheeling branch and the second freewheeling branch are both provided with branch switch components;

[0009] When the power switch is closed and the branch switches are all disconnected, the output of the power supply unit supplies power to the load via the first line inductance group and the second line inductance group for coating;

[0010] When the branch circuit switch components are all closed and the power switch component is disconnected, two network absorption loops are formed on both sides of the power switch component to synchronously consume arc energy in the network absorption loop.

[0011] Preferably, the first freewheeling branch and the second freewheeling branch each include at least a switch element for controlling the opening and closing of the branch, and an energy-consuming element for consuming circuit energy, and the switch elements on the first freewheeling branch and the second freewheeling branch are opened synchronously.

[0012] Preferably, the first freewheeling branch freewheels the first line inductance group, and the power supply unit, the first freewheeling branch and the first line inductance group form a first energy absorption loop, and the energy in the consumption loop is absorbed by the first energy consumption element in the first freewheeling branch;

[0013] The second freewheeling branch freewheels the second line inductance group, and the load, the second line inductance group and the second freewheeling branch form a second energy absorption loop, and the energy in the consumption loop is absorbed by the second energy consumption element in the second freewheeling branch.

[0014] Preferably, the first line inductance group includes a first line inductance and a second line inductance, and the first line inductance and the second line inductance are respectively connected in series to the output positive and negative electrodes of the power supply unit;

[0015] The first freewheeling branch includes a first switch element and the first energy-consuming element connected in series, one end of the first switch element is connected in parallel between the first line inductor and the positive output electrode of the power supply, and one end of the first energy-consuming element is connected in parallel between the first line inductor and the negative output electrode of the power supply.

[0016] Preferably, the second line inductor group includes a third line inductor and a fourth line inductor, and the third line inductor and the fourth line inductor are respectively connected in series to the positive and negative electrodes of the power output;

[0017] The second freewheeling branch includes an absorption circuit and a switch circuit connected in parallel;

[0018] One common end of the absorption circuit and the switch circuit is connected in parallel between the first line inductance and the positive pole of the power supply output, and the other common end of the absorption circuit and the switch circuit is connected in parallel between the second line inductance and the negative pole of the power supply.

[0019] Preferably, the absorption circuit includes a diode, a capacitor and the second energy consumption element;

[0020] The diode and the second energy dissipation element are connected in parallel, and a common end of the parallel connection is connected in series with one end of the capacitor. The other end of the capacitor and the other common end of the diode and the second energy dissipation element are connected to the positive and negative poles of the power supply output respectively.

[0021] Preferably, the first energy dissipation element and the second energy dissipation element are both resistors.

[0022] Preferably, the power switch element, the first switch element and the second switch element are respectively one of a power switch tube and a mechanical switch element;

[0023] The power switch component, the first switch component and the second switch component are connected to a control system and are controlled to be turned on or off according to the coating state of the load.

[0024] Compared with the prior art, the advantages of the present invention are:

[0025] The present invention connects a power switch in series between the output end of the power supply unit and the output end of the power supply, and when an arc is detected, the power supply output is quickly shut down by disconnecting the power switch. A wire inductor is connected in series to the power supply output end and the power supply output end, respectively, so as to absorb more arc energy, effectively suppress arc current, and protect the power supply.

[0026] Based on the rapid shutdown of power supply output and arc current suppression by inductance, a first freewheeling branch is connected in parallel to the output end of the power supply unit, and a second freewheeling branch is connected in parallel to the output end of the power supply. The first freewheeling branch and the power supply unit and the line inductance connected in series constitute a first energy absorption circuit, and the second freewheeling branch and the power supply output end and the line inductance connected in series constitute a second energy absorption circuit. The network circuits on both sides of the power switch respectively provide freewheeling to the corresponding inductors to maintain a stable change in the circuit current and absorb energy synchronously. The energy stored in the internal filter circuit of the power supply and the line inductance can be quickly absorbed, thereby improving the arc extinguishing efficiency and making the arc extinguishing more thorough, thereby ensuring the safety and stability of the power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0028] Figure 1 It is a schematic diagram of the principle of the coating power supply circuit of the present invention;

[0029] Figure 2 It is a schematic diagram of the operation of the coating power supply circuit of the present invention under normal coating state;

[0030] Figure 3 It is a schematic diagram of the working state of the coating power supply circuit of the present invention when an arc occurs and the arc is extinguished;

[0031] Figure 4 is a schematic diagram of the power supply unit of the present invention;

[0032] Among them: 1. first freewheeling branch; 2. second freewheeling branch; 3. first line inductance group; 4. second line inductance group; 5. power supply unit; 6. power switch component; 7. vacuum chamber; 8. first energy absorption circuit; 9. second energy absorption circuit; 10. arc extinguishing circuit. DETAILED DESCRIPTION

[0033] The present invention is further described in detail below in conjunction with specific embodiments:

[0034] For ease of understanding, the application scenario of the present invention is first described. The present invention is used for the internal circuit of a coating power supply. The specific circuit structure is shown in the attached Figure 1 The vacuum chamber 7 is used as a load, and the metal substrate is coated inside the vacuum chamber 7. The power circuit provides electrical energy. Arcing may occur during the coating process. The current in the circuit is several times higher than the normal operating current, and the power output is close to a short-circuit state, threatening the power safety. Therefore, when an arc is detected, it is necessary to quickly shut down the output and suppress or absorb the arc energy to avoid abnormal increase in circuit current caused by the arc and protect the power safety.

[0035] like Figure 1 As shown, a coating power supply circuit includes a power supply unit 5, a first line inductance group 3 is connected in series to the output end of the power supply unit 5, and a second line inductance group 4 is connected in series to the output end of the power supply. The inductors in the first line inductance group 3 and the second line inductance group 4 filter the output of the power supply part to remove high frequencies and retain low frequencies.

[0036] A power switch 6 is provided in series on a transmission line connecting the power supply unit 5 to a load (in this embodiment, the load refers to the vacuum chamber 7 ), and an arc extinguishing circuit 10 is provided in parallel.

[0037] In actual applications, there may be a switch for controlling the output in the internal structure of the power supply unit 5. For the convenience of description, in the embodiment of the present invention, it is assumed that the power supply unit 5 is in a normal power supply state, and the on and off of the power circuit is controlled by the power switch 6.

[0038] Specifically, the arc extinguishing circuit 10 includes a first freewheeling branch 1 and a second freewheeling branch 2 , and the power switch element 6 is connected in series between common ends of the first freewheeling branch 1 and the second freewheeling branch 2 on the same side.

[0039] Among them, the first freewheeling branch 1 and the second freewheeling branch 2 both include at least a switch element for controlling the opening and closing of the branch, and an energy-consuming element for consuming circuit energy, and the switch elements on the first freewheeling branch 1 and the second freewheeling branch 2 are opened synchronously.

[0040] In normal operation, refer to the attached Figure 2 , power switch 6 (eg, in the circuit diagram) ) is closed, the arc extinguishing circuit 10 is disconnected as a whole and does not work ( ), the output of the power supply unit 5 supplies power to the vacuum chamber 7 via the first line inductance group 3 and the second line inductance group 4 for coating.

[0041] When an arc occurs, disconnect the power switch 6, quickly shut down the power output, and simultaneously open , the first freewheeling branch 1 and the second freewheeling branch 2 are turned on, forming two independent network absorption loops on both sides of the power switch 6.

[0042] As attached Figure 3 As shown, on the left side of the turned-off power switch 6, the first line inductance group 3 includes the first line inductance And the second line , first line feeling And the second line They are respectively connected in series to the positive and negative output electrodes of the power supply unit 5; Closed, the first freewheeling branch 1 is connected to the first line inductor And the second line sense Continue to flow, keep the first line feeling And the second line sense The internal current changes relatively smoothly.

[0043] Similarly, on the right side of the power switch 6, the second line inductor group 4 includes the third line inductor And the fourth line of feeling , the third line sense And the fourth line of feeling Connect in series to the positive and negative poles of the power supply output respectively. Closed, the second freewheeling branch 2 is inductive to the third line And the fourth line of feeling Continue current, keep the third line sense And the fourth line of feeling The internal current changes relatively smoothly to avoid sudden changes (jumps).

[0044] The power circuit is in arc extinguishing working state:

[0045] Power supply unit 5, first freewheeling branch 1, first line inductor And the second line sense A complete first energy absorption loop 8 is formed, and the energy in the consumption loop is absorbed by the first energy consumption element in the first freewheeling branch 1. The first energy consumption element is a resistor, as shown in the attached Figure 3 Resistance in .

[0046] Vacuum chamber 7, third line sensor And the fourth line of feeling The second freewheeling branch 2 and the second energy absorption circuit 9 are formed, and the energy in the consumption circuit is absorbed by the second energy consumption element in the second freewheeling branch 2. The second energy consumption element is a resistor, as shown in the attached Figure 3 Resistance in .

[0047] resistance and resistor A power resistor is used. The resistor is an energy-consuming element. The greater its power, the higher its energy consumption efficiency. However, the greater the resistor power, the larger its corresponding volume. Since the power circuit is limited by the installation space when used as a whole, it is necessary to balance the power (dissipation efficiency) and volume (installation space) of the resistor during specific implementation.

[0048] In detail, the first freewheeling branch 1 includes a first switch element connected in series and the first energy dissipating element, the resistor , the first switch One end is connected in parallel to the first line sense and the positive electrode of the power supply output, one end of the first energy dissipation element is connected in parallel to the second line inductor and between the negative electrode of the power supply output; the first switch element controls the first freewheeling branch 1 to be disconnected.

[0049] In the arc energy absorption state, the specific flow direction of the current in the first energy absorption loop 8 on the left side of the power switch 6 is shown in the attached figure. Figure 3 As shown in FIG. 1 , the current of the first energy absorption loop 8 is from the first line inductor The current flowing through the first switch element of the first freewheeling branch and resistor and through the second line sense Flows through the power supply unit 5, and then flows from the first line Outflow to resistor , so the closed loop, in the cycle process, through the resistor Constantly consuming the first line of feeling , second line sense And the energy temporarily stored in the power supply unit 5.

[0050] The second freewheeling branch 2 includes an absorption circuit and a switch circuit connected in parallel.

[0051] The common end of the absorption circuit and the switch circuit is connected in parallel to the first line inductor. The other side of the common end of the absorption circuit and the switch circuit is connected in parallel to the second line inductor. and the negative terminal of the power supply.

[0052] Among them, the absorption circuit adopts RCD circuit, including diode ,capacitance And resistor (i.e., the second energy dissipating element); diode and resistor A common terminal and a capacitor in parallel One end in series; capacitor The other end of the diode and resistor The other common end of the parallel connection is connected to the positive and negative poles of the power supply output respectively.

[0053] In normal operation, the power supply unit 5 supplies the capacitor Medium charge, capacitor After the short-term fast charging is completed, the absorption circuit is disconnected and is in an open circuit state.

[0054] The switch circuit includes a second switch element, such as Figure 3 Switches in .

[0055] In the arc energy absorption state, the current flow direction in the second energy absorption loop 9 on the right side of the power switch 6 is as shown in the attached figure. Figure 3 As shown in FIG. 1 , the second switch element After closing, the capacitor Discharge, on the one hand, the current flows from the capacitor Flows through the positive output of the power supply, giving the third line a sense And the fourth line of feeling Freewheeling, third line sense And the fourth line of feeling The current drops steadily and rapidly, and the current flows through the negative electrode of the power supply output terminal through the resistor , forming a loop, on the other hand, the capacitor The current flows through the second switch element Flow resistance on the side , forming a loop.

[0056] Since the second switch The branch has no load, capacitor The energy consumption is mainly caused by the second switch and resistor The formed loop is used to cycle consumption and absorption. During the energy absorption process, the third line senses And the fourth line of feeling And resistor The current in the third line decreases until it reaches zero, and And the fourth line of feeling The current ends faster and ends faster than the resistance Earlier.

[0057] In capacitor Both sides form a loop, the resistance Capacitance , third line sense And the fourth line of feeling The released energy is dissipated. At the moment when the power switch 6 is disconnected, the resistor Protect ,avoid High current shock caused by short circuit.

[0058] When the arc is detected by the output voltage and current, and the arc energy is absorbed in the circuit, the power switch 6 is closed ( ), disconnect the first switch element and a second switch element , the power circuit returns to normal operation and continues coating.

[0059] Power switch 6 ( )、The first switch and a second switch element A power switch tube (such as a MOS tube, an IGBT device) and a mechanical switch element are respectively used.

[0060] First switch , the second switch And the power switch 6 ( ) are connected to the control system and are controlled to be turned on or off according to the coating state in the vacuum chamber 7. The control system can be a hardware circuit (e.g., an analog circuit) or a software processor, such as a DSP (digital signal processor), FPGA (field programmable gate array), or MCU (microcontroller unit).

[0061] During the coating process, whether an arc occurs and whether the arc energy in the circuit is completely absorbed are both based on circuit detection and depend on the specific circumstances.

[0062] For example, when the current-voltage curve in the coating process in the vacuum chamber 7 is detected, and the voltage curve decreases while the current increases, it is determined that an arc has occurred in the circuit, and the power supply needs to be disconnected to suppress and absorb the arc energy.

[0063] When it is detected that the inside of the vacuum chamber 7 cools down rapidly (the voltage and current of the equivalent load in the corresponding chamber are reduced to 0), it is determined that the circuit energy absorption is complete, and the power supply is restarted again to restore the normal coating state.

[0064] In this embodiment, the power supply unit 5 adopts a combination of a transformer and a diode rectifier circuit, as shown in the attached Figure 4 As shown in , electrical isolation is performed through an isolation transformer, a rectifier diode is connected to the secondary side of the transformer for rectification, and a filter capacitor is used for filtering after rectification, so that the output of the power supply unit is close to DC.

[0065] Compared with the prior art, this embodiment has the following characteristics:

[0066] The present invention connects a power switch in series between the output end of the power supply unit and the output end of the power supply, and when an arc is found, the power switch is disconnected to quickly shut down the power output;

[0067] A line inductor is connected in series at the power supply output terminal and the power supply output terminal respectively, and the line inductor can absorb arc energy, suppress arc energy in the circuit, and protect the power supply;

[0068] The first freewheeling branch 1 is connected in parallel to the output end of the power supply unit, and the second freewheeling branch 2 is connected in parallel to the output end of the power supply. The first freewheeling branch 1 and the power supply unit 5 and the line inductance ( , ) constitutes the first energy absorption loop 8, the second freewheeling branch 2 and the power supply output end and the line inductance ( , ) constitutes a second energy absorption circuit 9, and the network circuits on both sides of the power switch 6 absorb energy synchronously, which can quickly absorb the energy stored in the internal filter circuit of the power supply and the lead inductance, realize rapid arc extinguishing, and ensure the safety and stability of the power supply.

[0069] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the scope of protection of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is limited by the attached claims rather than the above description, and it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present invention.

Claims

1. A coating power supply circuit, characterized in that: It comprises a power supply unit, a first line inductance group is connected in series to the output end of the power supply unit, a first freewheeling branch and a second freewheeling branch are connected in parallel between the output end of the power supply unit and the output end of the power supply, a power switch is connected in series on the main road where the output end of the power supply unit is connected to the output end of the power supply; the output end of the power supply is connected to the load via the second line inductance group in series; The first freewheeling branch and the second freewheeling branch are both provided with branch switch elements, and the switch elements on the first freewheeling branch and the second freewheeling branch are turned on synchronously; When the power switch is closed and the branch switches are all disconnected, the output of the power supply unit supplies power to the load via the first line inductance group and the second line inductance group for coating; When the branch circuit switch components are all closed and the power switch component is disconnected, two network absorption loops are formed on both sides of the power switch component to synchronously consume the arc energy in the network absorption loop; Wherein, the first freewheeling branch and the second freewheeling branch each include at least a switch element for controlling the opening and closing of the branch, and an energy-consuming element for consuming circuit energy; The first freewheeling branch freewheels the first line inductance group, and the power supply unit, the first freewheeling branch and the first line inductance group form a first energy absorption loop, and the energy in the consumption loop is absorbed by the first energy consumption element in the first freewheeling branch; Wherein, the first line inductance group includes a first line inductance and a second line inductance, and the first line inductance and the second line inductance are respectively connected in series to the output positive and negative electrodes of the power supply unit; The first freewheeling branch comprises a first switch element and the first energy-consuming element connected in series, one end of the first switch element is connected in parallel between the first line inductance and the positive electrode of the power supply output, and one end of the first energy-consuming element is connected in parallel between the second line inductance and the negative electrode of the power supply output; The second freewheeling branch freewheels the second line inductance group, and the load, the second line inductance group and the second freewheeling branch form a second energy absorption loop, and the energy in the consumption loop is absorbed by the second energy consumption element in the second freewheeling branch; The second line inductance group includes a third line inductance and a fourth line inductance, and the third line inductance and the fourth line inductance are respectively connected in series to the positive and negative electrodes of the power output; The second freewheeling branch includes an absorption circuit and a switch circuit connected in parallel; One common end of the absorption circuit and the switch circuit is connected in parallel between the first line inductance and the positive pole of the power supply output, and the other common end of the absorption circuit and the switch circuit is connected in parallel between the second line inductance and the negative pole of the power supply.

2. A coating power supply circuit according to claim 1, characterized in that: The absorption circuit includes a diode, a capacitor and the second energy consumption element; The diode and the second energy dissipation element are connected in parallel, and a common end of the parallel connection is connected in series with one end of the capacitor. The other end of the capacitor and the other common end of the diode and the second energy dissipation element are connected to the positive and negative poles of the power supply output respectively.

3. A coating power supply circuit according to claim 1, characterized in that: The first energy consumption element and the second energy consumption element are both resistors.

4. A coating power supply circuit according to claim 1, characterized in that: The power switch component, the first switch component and the second switch component are respectively one of a power switch tube and a mechanical switch component; The power switch component, the first switch component and the second switch component are connected to a control system and are controlled to be turned on or off according to the coating state of the load.

Images