Power supply device and control method thereof

Abstract

The present invention relates to a power supply device and a control method thereof. The power unit includes an output terminal and outputs an output voltage. The electrolytic cell has an electrolyte. The anode is arranged in the electrolyte and connected to the output terminal of the power unit. The cathode is arranged in the electrolyte and connected to the output terminal of the power unit. The metal foil is arranged on the anode to perform chemical formation according to the output voltage. The control unit is connected to the power unit to control the output voltage of the power unit to have a constant voltage region, an upward voltage pulse region and a downward voltage pulse region, wherein the valley value of the downward voltage pulse region satisfies the following relationship: 0<U min ≤V fn , where V fn is the voltage value in the constant voltage zone, U min is the valley value of the downward voltage pulse region.

Description

Technical Field

[0001] The invention relates to a power supply device and a control method thereof, and in particular to a power supply device and a control method thereof for metal foil formation. Background Art

[0002] Aluminum electrolytic capacitors contain at least a positive electrode, a negative electrode and an electrolyte. Metal foil is a material specifically used to make the positive and negative electrodes of aluminum electrolytic capacitors, and is mainly used to store charge. The metal foil is made of high-purity aluminum foil as the main raw material, and is formed through a series of processing processes such as corrosion and chemical formation. The production process of aluminum electrolytic capacitors is further explained as follows: the anode aluminum foil that has been corroded and covered with a dielectric layer (i.e., an oxide film), the corroded cathode aluminum foil and the electrolytic paper are wound, then impregnated with an electrolyte and sealed in an aluminum shell.

[0003] The quality of metal foil can decisively affect the overall performance of aluminum electrolytic capacitors, among which the corrosion process and chemical formation process of metal foil directly determine the capacity, leakage current, loss, life, reliability and volume of aluminum electrolytic capacitors. For example, when the specific capacitance of metal foil is higher, the unit charge of metal foil is higher, and the volume of aluminum electrolytic capacitors that can be made under the same voltage is smaller. Therefore, metal foil is the part with the highest technical content and added value in aluminum electrolytic capacitors.

[0004] The chemical formation process refers to placing the anode aluminum foil in an electrolyte and applying a DC high voltage to the anode aluminum foil. After the electrolysis reaction and oxidation reaction, an oxide film is formed on the surface of the anode aluminum foil. The chemical formation process directly affects the formation quality of the oxide film, that is, it controls the aluminum oxide (γ-Al 2 O 3 ) is arranged uniformly and densely, or whether there are extra impurity ions in the oxide film, which in turn determines the dielectric constant, leakage current and withstand voltage of the aluminum electrolytic capacitor, and ultimately determines the capacity and service life of the aluminum electrolytic capacitor. Therefore, improving the formation quality of the oxide film on the anode aluminum foil by improving the chemical formation process is a research goal for those skilled in the art.

[0005] Therefore, how to develop a power supply device and a control method thereof for improving the formation quality is an urgent need at present. Summary of the invention

[0006] The purpose of the present invention is to provide a power supply device and a control method thereof, which uses a control unit to control the output voltage output by the power unit to have an upward voltage pulse area, a downward voltage pulse area and a constant voltage area, or controls the output current output by the power unit to have an upward current pulse area, a downward current pulse area and a constant current area, so as to achieve the effect of destroying the weak area in the oxide film, slowing down the dissolution and destruction process, and regenerating and filling the metal foil in the dissolution area, thereby improving the quality of the oxide film, and further improving the capacity and service life of the aluminum electrolytic capacitor. In addition, according to the relationship that the valley value of the downward voltage pulse area (or the downward current pulse area) needs to satisfy, it can be known that the valley value of the downward voltage pulse area (or the downward current pulse area) needs to be greater than 0, which can ensure that the electrode polarity in the electrolytic cell will not be reversed, thereby avoiding corrosion and dissolution of the metal material constituting the cathode. The valley value of the downward voltage pulse area is much lower than the peak value of the upward voltage pulse area, and the valley value of the downward current pulse area is much lower than the peak value of the upward current pulse area, which can produce a larger local voltage and current drop effect, so as to quickly complete the depolarization and dissolution process of the oxide film, reduce the dynamic repair time, and thus reduce the energy consumption of the overall power supply device.

[0007] To achieve the above-mentioned purpose, one embodiment of the present invention is to provide a control method, which is applied to a power supply device, and the power supply device includes a power unit and a control unit, wherein the control method includes the following steps. First, an electrolytic cell is provided, wherein the electrolytic cell has an electrolyte, an anode and a cathode are arranged in the electrolyte, and a metal foil is arranged on the anode. Next, the output end of the power unit is connected to the anode and the cathode, and the power unit outputs an output voltage for chemically forming the metal foil. Next, the steps are executed, and the control unit controls the power unit so that the output voltage has a constant voltage region, an upward voltage pulse region, and a downward voltage pulse region, wherein the valley value of the downward voltage pulse region satisfies the following relationship: 0<U min ≤V fn , where V fn is the voltage value in the constant voltage zone, U min is the valley value of the downward voltage pulse region.

[0008] To achieve the above-mentioned purpose, another embodiment of the present invention is to provide a control method, which is applied to a power supply device, and the power supply device includes a power unit and a control unit, wherein the control method includes the following steps. First, an electrolytic cell is provided, wherein the electrolytic cell has an electrolyte, an anode and a cathode are arranged in the electrolyte, and a metal foil is arranged on the anode. Next, the output end of the power unit is connected to the anode and the cathode, and the power unit outputs an output current for chemically forming the metal foil. Next, the control unit controls the power unit so that the output current has a constant current region, an upward current pulse region, and a downward current pulse region, wherein the valley values ​​of the downward current pulse region respectively satisfy the following relationship: 0<I min ≤I fn , where Ifn is the current value in the constant current region, I min is the valley value of the downward current pulse region.

[0009] To achieve the above-mentioned purpose, another embodiment of the present invention is to provide a formation system, including a power unit, an electrolytic cell, an anode, a cathode, a metal foil and a control unit. The power unit includes at least one output terminal and outputs an output voltage. The electrolytic cell has an electrolyte. The anode is disposed in the electrolyte and connected to at least one output terminal of the power unit. The cathode is disposed in the electrolyte and connected to at least one output terminal of the power unit. The metal foil is disposed on the anode to perform formation according to the output voltage. The control unit is connected to the power unit to control the power unit so that the output voltage has a constant voltage region, an upward voltage pulse region and a downward voltage pulse region, wherein the valley value of the downward voltage pulse region satisfies the following relationship: 0<U min ≤V fn , where V fn is the voltage value in the constant voltage zone, U min is the valley value of the downward voltage pulse region.

[0010] To achieve the above-mentioned purpose, another embodiment of the present invention is to provide a power supply device, including a power unit, an electrolytic cell, an anode, a cathode, a metal foil and a control unit. The power unit includes at least one output terminal and outputs an output current. The electrolytic cell has an electrolyte. The anode is disposed in the electrolyte and is connected to at least one output terminal of the power unit. The cathode is disposed in the electrolyte and is connected to at least one output terminal of the power unit. The metal foil is disposed on the anode to be formed according to the output current. The control unit is connected to the power unit to control the power unit so that the output current has a constant current region, an upward current pulse region and a downward current pulse region, wherein the valley value of the downward current pulse region satisfies the following relationship: 0<I min ≤I fn , where I fn is the current value in the constant current region, I min is the valley value of the downward current pulse region.

[0011] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments, but is not intended to limit the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of the chemical formation system of the present invention;

[0013] Figure 2A for Figure 1 The enlarged schematic diagram of the partial structure of the metal foil of the chemical formation system forming the etched hole;

[0014] Figure 2B for Figure 1The enlarged schematic diagram of the partial structure of the metal foil forming oxide film of the chemical formation system shown;

[0015] Figure 3A It is a simplified structural diagram of an aluminum electrolytic capacitor;

[0016] Figure 3B It is the equivalent circuit structure diagram of aluminum electrolytic capacitor;

[0017] Figure 3C It is a simplified equivalent circuit structure diagram of an aluminum electrolytic capacitor;

[0018] Figure 4A This is the waveform of the leakage current of the aluminum electrolytic capacitor;

[0019] Figure 4B for Figure 1 The waveform diagram of the output voltage and output current provided by the power unit of the power supply device of the formation system shown;

[0020] Figure 5A for Figure 1 The voltage and current waveform diagram of the first embodiment of the output voltage and output current provided by the power unit of the power supply device of the formation system shown;

[0021] Figure 5B for Figure 5A A flow chart of a method for controlling the output voltage and output current provided by a power unit of a power supply device of a formation system shown;

[0022] Fig. 6A for Figure 1 The voltage and current waveform diagram of the second embodiment of the output voltage and output current provided by the power unit of the power supply device of the formation system shown;

[0023] Figure 6B for Fig. 6A A flow chart of a method for controlling the output voltage and output current provided by a power unit of a power supply device of a formation system shown;

[0024] Fig. 7A for Figure 1 The voltage and current waveform diagram of the third embodiment of the output voltage and output current provided by the power unit of the power supply device of the formation system shown in FIG.

[0025] Figure 7B for Figure 1 The voltage and current waveform diagram of the fourth embodiment of the output voltage and output current provided by the power unit of the power supply device of the formation system shown in FIG.

[0026] Figure 7C for Figure 1The voltage and current waveform diagram of the fifth embodiment of the output voltage and output current provided by the power unit of the power supply device of the formation system shown in FIG.

[0027] Fig. 8A for Figure 1 A voltage waveform diagram of a sixth embodiment of an output voltage provided by a power unit of a power supply device of a formation system shown in FIG.

[0028] Figure 8B for Figure 1 FIG. 1 is a current waveform diagram of a seventh embodiment of an output current provided by a power unit of a power supply device of a formation system.

[0029] Among them, the reference numerals

[0030] 1: Power supply unit

[0031] 2: Electrolyzer

[0032] 21: Electrolyte

[0033] 3: Power unit

[0034] 31, 32: Output terminal

[0035] 4: Cathode

[0036] 5: Anode

[0037] 6: Control unit

[0038] 7: Metal foil

[0039] 8: Oxide film

[0040] Ca: anode capacitance

[0041] Cc: cathode capacitance

[0042] Ce: electrolyte equivalent capacitance

[0043] Rs: equivalent conduction resistance

[0044] Rdc1: Equivalent dielectric leakage resistance

[0045] Re: Equivalent resistance of electrolyte and electrolytic paper

[0046] ESL: equivalent inductance

[0047] V1: Constant voltage area

[0048] V2: Upward voltage pulse area

[0049] V3: Downward voltage pulse area

[0050] U max : Peak value of upward voltage pulse area

[0051] U min : Valley value of downward voltage pulse area

[0052] I1: Constant current area

[0053] I2: Upward current pulse area

[0054] I3: Downward current pulse area

[0055] I max : Peak value of upward current pulse area

[0056] I min : Valley value of downward current pulse area

[0057] S1-S3, M1-M3: Steps DETAILED DESCRIPTION

[0058] Some typical embodiments that embody the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various changes in different aspects without departing from the scope of the present invention, and the description and drawings therein are essentially used for illustrative purposes rather than for limiting the present invention.

[0059] See also Figure 1 , which is a schematic diagram of the structure of the chemical formation system of the present invention. Figure 1 As shown, the chemical formation system 1 of the present invention comprises a power supply device, an electrolytic cell 2, a cathode 4, an anode 5 and a metal foil 7. The power supply device comprises a power unit 3 and a control unit 6. The electrolytic cell 2 has an electrolyte 21, and the electrolyte 21 is an acidic solution with medium dissolving power, such as phosphoric acid, oxalic acid, boric acid, chromic acid and citric acid. The power unit 3 has two output ends 31 and 32, wherein the power unit 3 outputs an output voltage and an output current through the two output ends 31 and 32. The cathode 4 can be composed of aluminum foil, which is arranged in the electrolyte 21 of the electrolytic cell 2 and connected to the output end 31 of the power unit 3. The anode 5 is composed of high-purity aluminum, and the number of the anodes 5 is multiple, wherein at least one anode 5 is arranged in the electrolyte 21 of the electrolytic cell 2, and at least one anode 5 is not arranged in the electrolyte 21 of the electrolytic cell 2 and is connected to the output end 32 of the power unit 3. The metal foil 7 is arranged on the anode 5. The control unit 6 is connected to the power unit 3 to control the power unit 3 and adjust the output voltage and output current provided by the power unit 3 to control the chemical formation process of the metal foil 7. The detailed features of the control unit 6 controlling the output voltage and output current provided by the power unit 3 will be described later. The chemical formation process of the metal foil 7 will be described below using diagrams.

[0060] See also Figure 2A and Figure 2B And cooperate Figure 1 ,in Figure 2A for Figure 1 The enlarged schematic diagram of the partial structure of the metal foil of the chemical formation system forming the etched hole is shown. Figure 2B for Figure 1 The enlarged schematic diagram of the partial structure of the metal foil forming oxide film in the chemical formation system shown. Figure 2A and Figure 2B In both Figure 1 The contact surface between the metal foil 7 and the electrolyte 21 in the electrolytic cell 2 is shown in the partial structure under different conditions. The chemical process steps of the metal foil 7 are as follows: the power unit 3 continuously provides output voltage and output current to the metal foil 7, so that the surface of the metal foil 7 produces an oxidation reaction, thereby forming an oxide film 8, such as Figure 2B At this time, the chemical reaction formula generated on the metal foil 7 is as follows: electrolysis of water, H 2 O--->O 2- +2H + , the reaction is exothermic; ionization of Al metal, Al--->3e-+Al 3+ ; Formation of alumina, 2Al 3+ +3O 2- --->Al 2 O 3 +1670kJ, the reaction is exothermic; at the same time, the borate ion impurities in the electrolyte will also react with the aluminum ions to produce an oxidation reaction, BO 3 3- +Al 3+ --->AlBO 3 The oxidation reaction of the impurity ions will weaken the breakdown resistance of the oxide film 8, resulting in a decrease in the quality of the oxide film 8. The main reaction on the cathode 4 is the reduction reaction of hydrogen, 2H + +2e---->H2. Due to the heat accumulation caused by the water electrolysis and oxidation reaction of the metal foil 7, the high temperature will lead to the dissolution side reaction of aluminum oxide, that is, the electrolyte 21 further corrodes the oxide film 8 formed on the metal foil 7, Al2O3+6H + --->2Al 3+ +3H2O, thereby damaging the oxide layer.

[0061] The following will further explain the process of the formation and dissolution of the oxide film 8 in three stages. The first stage is the formation of a non-porous layer of the oxide film 8. In the initial stage when the power unit 3 provides output voltage and output current, for example, in the first few seconds to tens of seconds, a dense oxide film 8 with high insulation performance is formed on the surface of the metal foil 7, wherein the thickness of the oxide film 8 is about 0.01 to 0.1 microns, and it is a continuous and non-porous thin film layer, which can hinder the flow of current. Since the thickness of the non-porous layer is proportional to the output voltage and inversely proportional to the dissolution rate of the oxide film 8 in the electrolyte 21, the voltage in this stage increases sharply from zero to the maximum value. The second stage is the formation of a porous layer of the oxide film 8. As the oxide film 8 is formed, the electrolyte 21 begins to dissolve the oxide film 8. Since the formation of the oxide film 8 is not uniform, the thinnest part of the oxide film 8 will be dissolved first to form holes, and the electrolyte 21 continues to react chemically with the metal foil 7 through the holes, resulting in the formation of a porous layer on the oxide film 8. The third stage is the thickening of the porous layer of the oxide film 8. When the non-porous layer is continuously dissolved and a porous layer is formed, the new non-porous layer continues to grow, so that the generation rate and dissolution rate of the non-porous layer of the oxide film 8 reach a balance, so that the thickness of the non-porous layer stops increasing, and the voltage changes slightly. However, since the generation and dissolution of the oxide film 8 at the bottom of the hole have not stopped, the hole deepens to form pores, and the oxide film 8 with pores continues to thicken. When the generation rate and dissolution rate of the oxide film 8 reach a dynamic balance, the thickness of the oxide film 8 remains unchanged.

[0062] During the generation and dissolution of the oxide film 8, if there are defects in the oxide film 8, the aluminum electrolytic capacitor may have reliability problems. For example, during the load process, the aluminum electrolytic capacitor uses electrolyte to repair and thicken the oxide film 8, which causes more electrolyte loss, increased viscosity, and increased resistivity, thereby increasing the equivalent series resistance of the electrolyte, resulting in a significant increase in the loss of the aluminum electrolytic capacitor. In addition, the viscosity of the electrolyte increases, and the metal foil 7 has different concave and convex shapes due to corrosion, making it difficult for the electrolyte to fully contact the oxide film 8, resulting in a reduction in the effective area of ​​the electrode plate of the aluminum electrolytic capacitor, a sharp drop in capacitance, and a reduction in the service life of the aluminum electrolytic capacitor. In addition, during the generation of the oxide film 8, gas is generated due to electrolysis, and the gas also increases as the generation time increases, which can easily cause the aluminum electrolytic capacitor to swell, leak or explode. Therefore, the quality of the oxide film 8 directly affects the performance of the aluminum electrolytic capacitor. The following will further explain the parameters and characteristics of the aluminum electrolytic capacitor that are related to the quality of the oxide film 8.

[0063] See also Figure 3A , Figure 3B and Figure 3C And cooperate Figure 1 ,in Figure 3A This is a simplified structural diagram of an aluminum electrolytic capacitor. Figure 3BIt is the equivalent circuit structure diagram of aluminum electrolytic capacitor. Figure 3C This is a simplified equivalent circuit diagram of an aluminum electrolytic capacitor. Figure 3A and Figure 3B As shown in the figure, Ca is the anode capacitance of the aluminum electrolytic capacitor, Cc is the cathode capacitance of the aluminum electrolytic capacitor, Ce is the equivalent capacitance of the electrolyte, Rs is the equivalent conduction resistance, where the equivalent conduction resistance includes dielectric loss and metal conductor resistance, Rdc1 is the equivalent dielectric leakage resistance, Re is the equivalent resistance of the electrolyte and electrolytic paper, and ESL is the equivalent inductance, which includes the winding metal foil and lead inductance. Figure 3C As shown in the figure, the equivalent conduction resistance Rs and the electrolyte equivalent resistance Re can be combined and simplified into the simplified resistance ESR. Since the cathode capacitance Cc is much larger than the anode capacitance Ca, and the anode capacitance Ca is much larger than the electrolyte equivalent capacitance Ce, Figure 3C The cathode capacitance Cc and the electrolyte equivalent capacitance Ce can be ignored, and only the anode capacitance Ca is shown.

[0064] Depend on Figure 3C It can be seen that the dielectric of the oxide film 8 has a great influence on blocking the DC current. Since the dielectric of the oxide film 8 is soaked with electrolyte, when the DC voltage is applied, a very small current will be generated when the oxide film is re-formed and repaired, which is called leakage current. The more defects the oxide film 8 has, the greater the leakage current will be. The repair reaction of the oxide film 8 caused by it will consume and dry up the limited electrolyte in the aluminum electrolytic capacitor. Please refer to Figure 4A and Figure 4B And cooperate Figure 1 ,in Figure 4A This is the waveform of the leakage current of the aluminum electrolytic capacitor. Figure 4B for Figure 1 The waveform diagram of the output voltage and output current provided by the power unit of the power supply device of the formation system is shown. Figure 4B The solid line shows the waveform of the output current provided by the power unit 3, and the dotted line shows the waveform of the output voltage provided by the power unit 3. Figure 4B As shown, when the time for the power unit 3 to provide the output voltage and output current is greater than a predetermined value, for example, after several tens of seconds, the output current provided by the power unit 3 drops to a stable state, so that the chemical formation process of the metal foil 7 is in a stable state. In the leakage current stage of this small current value, the defective area on the metal foil 7 where the oxide film 8 is insufficient will undergo dynamic dissolution and oxidation reaction until a new oxide film is formed.

[0065] Therefore, in order to avoid the reliability problems caused by the aforementioned oxide film 8 during the generation and dissolution process and to improve the quality of the oxide film 8, the present invention will be further described below in which the output voltage or output current provided by the power unit 3 is adjusted to improve the quality of the oxide film 8. Figure 5A And cooperate Figure 1 ,in Figure 5A for Figure 1 The voltage and current waveform diagram of the first embodiment of the output voltage and output current provided by the power unit of the power supply device of the formation system shown in the figure. In this embodiment, the control unit 6 controls the output voltage of the power unit 3 to have a constant voltage region V1, an upward voltage pulse region V2 and a downward voltage pulse region V3, wherein the constant voltage region V1, the upward voltage pulse region V2 and the downward voltage pulse region V3 of the output voltage are constant, wherein the peak value of the upward voltage pulse region V2 and the valley value of the downward voltage pulse region V3 respectively satisfy the following relationship,

[0066] V fn <U max ≤(1+k 1n )V fn

[0067] 0<U min ≤V fn

[0068] Where V fn is the voltage value of the constant voltage region V1, where the ripple coefficient of the constant voltage region V1 is ≤±2%, U max is the peak value of the upward voltage pulse region V2, U min is the valley value of the downward voltage pulse region V3, k 1n is the voltage adjustment coefficient preset in the control unit 6, where 2%≤k 1n ≤20%. In this embodiment, the peak value U of the upward voltage pulse region V2 max The value of is different from the valley value U of the downward voltage pulse area V3 min The numerical size of .

[0069] When the control unit 6 controls the output voltage of the power unit 3 to be in the upward voltage pulse area V2, the output current of the power unit 3 has a corresponding rising current. At this time, the electric field strength on the oxide film 8 increases with , thereby fully destroying the weak defect area (such as impurity defects, crack defects, and the outermost hydrated aluminum oxide layer) in the oxide film 8, accelerating its dissolution, and then exposing the fresh aluminum substrate of the metal foil 7, reducing the dynamic repair time, and achieving the effect of energy saving. When the control unit 6 controls the output voltage of the power unit 3 to be in the downward voltage pulse area V3, the output current of the power unit 3 has a corresponding falling current. At this time, the electric field strength on the oxide film 8 decreases with , which can prevent the accumulation of heat on the metal foil 7 and reduce the temperature of the metal foil 7, thereby inhibiting the dissolution side reaction of the oxide film 8, preventing the expansion of the dissolution area, reducing the damage to the oxide film 8, and at the same time, the oxidation reaction of the impurity ions is weakened, thereby reducing the impurities in the oxide film 8. When the control unit 6 controls the output voltage of the power unit 3 to be in the constant voltage area V1, the output current of the power unit 3 is also in a steady current state, and the oxide film 8 is regenerated and filled in the dissolution area, making the oxide film 8 denser and improving its quality.

[0070] According to the relationship that the valley value of the downward voltage pulse zone V3 needs to satisfy, the valley value of the downward voltage pulse zone V3 needs to be greater than 0, which can ensure that the electrode polarity in the electrolytic cell 2 will not be reversed, such as the cathode turning into the anode, and avoid the reversal of polarity causing the metal material (such as stainless steel) of the cathode plate device to corrode and dissolve, thereby damaging existing equipment and having poor compatibility. In addition, if the lower limit of the downward voltage pulse zone is greater than and close to the amplitude "zero", this will produce a greater local voltage drop effect, thereby completing the dissolution process of the defective part more quickly, providing sufficient time for subsequent re-oxidation repair.

[0071] In addition, in order to ensure appropriate and sufficient dissolution time and oxidation time, the pulse width time of the upward voltage pulse zone V2 and the pulse width time of the downward voltage pulse zone V3 need to be adjusted within the preset range. Figure 5AIn this embodiment, the upward voltage pulse zone V2 is continuous with the next adjacent downward voltage pulse zone V3, and the time from the starting point A1 of the pulse width time of the upward voltage pulse zone V2 to the ending point A2 of the pulse width time of the next adjacent downward voltage pulse zone V3 is between 1 and 100 seconds, which means that the frequencies of the upward voltage pulse zone V2 and the downward voltage pulse zone V3 are between 0.01 and 1 Hz. In this embodiment, the upward voltage pulse zone V2 includes one upward voltage pulse, and the downward voltage pulse zone V3 includes one downward voltage pulse. In other embodiments, the upward voltage pulse zone V2 includes multiple upward voltage pulses, and the downward voltage pulse zone V3 includes multiple downward voltage pulses. In other embodiments, the upward voltage pulse zone V2 and the next adjacent downward voltage pulse zone V3 may also be discontinuous, and may also be a combination of multiple, symmetrical or asymmetrical, adjacent or intermittent. In this case, the time from the starting point A1 of the pulse width time of the upward voltage pulse zone V2 to the ending point A2 of the pulse width time of the next adjacent downward voltage pulse zone V3 also needs to be between 1 and 100 seconds. In some embodiments, the downward voltage pulse zone V3 is located before the adjacent upward voltage pulse zone V2, and the time between the starting point of the pulse width time of the downward voltage pulse zone V3 and the ending point of the pulse width time of the next adjacent upward voltage pulse zone V2 also needs to be between 1 and 100 seconds.

[0072] See also Figure 5B And cooperate Figure 1 and Figure 5A ,in Figure 5B for Figure 5A The flowchart of the control method of the output voltage and output current provided by the power unit of the power supply device of the chemical formation system shown. First, execute step S1, provide an electrolytic cell 2, the electrolytic cell 2 has an electrolyte 21, the anode 5 and the cathode 4 are arranged in the electrolyte 21, and the metal foil 7 is arranged on the anode 5. Then, execute step S2, connect the output ends 31 and 32 of the power unit 3 to the anode 5 and the cathode 4, and the power unit 3 outputs an output voltage for chemical formation of the metal foil 7. Then, execute step S3, the control unit 6 controls the power unit 3 so that the output voltage has a constant voltage area V1, an upward voltage pulse area V2 and a downward voltage pulse area V3, wherein the valley value of the downward voltage pulse area V2 satisfies the following relationship: 0<U min ≤V fn , where V fn is the voltage value of the constant voltage zone V1, U min It is the valley value of the downward voltage pulse region V3.

[0073] See also Fig. 6A And cooperate Figure 1 ,in Fig. 6A for Figure 1The voltage and current waveform diagram of the second embodiment of the output voltage and output current provided by the power unit of the power supply device of the formation system shown in the figure. In this embodiment, the control unit 6 controls the output current of the power unit 3 to have a constant current region I1, an upward current pulse region I2 and a downward current pulse region I3, wherein the constant current region I1, the upward current pulse region I2 and the downward current pulse region I3 of the output current are constant, wherein the peak value of the upward current pulse region I2 and the valley value of the downward current pulse region I3 respectively satisfy the following relationship,

[0074] I fn <I max ≤(1+k 2n )I fn

[0075] 0<I min ≤I fn

[0076] Among them I fn is the current value of the constant current region I1, where the ripple coefficient of the constant current region I1 is ≤±2%, I max is the peak value of the upward current pulse region I2, I min is the valley value k of the downward current pulse region I3 2n is the current adjustment coefficient preset in the control unit 6, where 2%≤k 2n ≤20%. In this embodiment, the peak value I max The value of is different from the valley value I in the downward current pulse area I3 min The numerical size of .

[0077] When the control unit 6 controls the output current of the power unit 3 to be in the upward current pulse area I2, the output voltage of the power unit 3 has a corresponding rising voltage. At this time, the electric field strength on the oxide film 8 increases accordingly, thereby fully destroying the weak defect area (such as impurity defects, crack defects, and the outermost hydrated aluminum oxide layer) in the oxide film 8, accelerating its dissolution, thereby exposing the fresh aluminum substrate of the metal foil 7, reducing the dynamic repair time, and achieving energy saving. When the control unit 6 controls the output current of the power unit 3 to be in the downward current pulse area I3, the output voltage of the power unit 3 has a corresponding falling voltage. At this time, the electric field strength on the oxide film 8 decreases, which can prevent the accumulation of heat on the metal foil 7 and reduce the temperature of the metal foil 7, thereby inhibiting the dissolution side reaction of the oxide film 8, preventing the expansion of the dissolution area, reducing the damage to the oxide film 8, and at the same time, the oxidation reaction of the impurity ions is weakened, thereby reducing the impurities in the oxide film 8. When the control unit 6 controls the output current of the power unit 3 to be in the constant current area I1, the output voltage of the power unit 3 is also in a stable voltage state, and the oxide film 8 is regenerated and filled in the dissolution area, making the oxide film 8 denser and improving its quality.

[0078] According to the relationship that the valley value of the downward current pulse zone I3 needs to satisfy, it can be known that the valley value of the downward current pulse zone I3 needs to be greater than 0, which can ensure that the electrode polarity in the electrolytic cell 2 will not be reversed, such as the cathode turning into the anode, and can avoid the reversal of polarity causing the metal material (such as stainless steel) of the cathode plate device to corrode and dissolve, thereby damaging existing equipment and having poor compatibility. In addition, if the lower limit of the downward current pulse zone I3 is greater than and close to the amplitude "zero", this will produce a greater local current drop effect, thereby completing the dissolution process of the defective part more quickly, providing sufficient time for subsequent re-oxidation repair.

[0079] In addition, in order to ensure appropriate and sufficient dissolution time and oxidation time, the pulse width time of the upward current pulse zone I2 and the pulse width time of the downward current pulse zone I3 need to be adjusted within the preset range. Fig. 6A In this embodiment, the upward current pulse zone I2 is continuous with the next adjacent downward current pulse zone I3, and the time between the starting point B1 of the pulse width time of the upward current pulse zone I2 and the ending point B2 of the pulse width time of the next adjacent downward current pulse zone I3 is between 1 and 100 seconds, which means that the frequencies of the upward current pulse zone I2 and the downward current pulse zone I3 are between 0.01 and 1 Hz. In this embodiment, the upward current pulse zone I2 includes an upward current pulse, and the downward current pulse zone I3 includes a downward current pulse. In some embodiments, the upward current pulse zone I2 includes multiple upward current pulses, and the downward current pulse zone I3 includes multiple downward current pulses. In other embodiments, the upward current pulse zone I2 and the next adjacent downward current pulse zone I3 may also be discontinuous, and may also be a combination of multiple, symmetrical or asymmetrical, adjacent or intermittent. In this case, the time between the starting point B1 of the pulse width time of the upward current pulse zone I2 and the ending point B2 of the pulse width time of the next adjacent downward current pulse zone I3 also needs to be between 1 and 100 seconds.

[0080] See also Figure 6B And cooperate Figure 1 and Fig. 6A ,in Figure 6B for Fig. 6AThe flowchart of the control method of the output voltage and output current provided by the power unit of the power supply device of the chemical formation system shown. First, execute step M1, provide an electrolytic cell 2, the electrolytic cell 2 has an electrolyte 21, the anode 5 and the cathode 4 are arranged in the electrolyte 21, and the metal foil 7 is arranged on the anode 5. Then, execute step M2, connect the output ends 31 and 32 of the power unit 3 to the anode 5 and the cathode 4, and the power unit 3 outputs an output current for chemical formation of the metal foil 7. Then, execute step M3, the control unit 6 controls the power unit 3 so that the output current has a constant current region I1, an upward current pulse region I2 and a downward current pulse region I3, wherein the valley value of the downward current pulse region I2 satisfies the following relationship: 0<I min ≤I fn , where I fn is the current value of constant current region I1, I min It is the valley value of the downward current pulse region I3.

[0081] In some embodiments, the upward voltage pulse area and the downward voltage pulse area are not limited to being constant, but can be curved or stepped. Of course, the upward current pulse area and the downward current pulse area are not limited to being constant, but can be curved or stepped. The stepped pulse area can make the oxide film 8 denser and reduce the time for subsequent repair of the oxide film 8, thereby reducing the power consumption per unit area. Fig. 7A , which is Figure 1 The voltage and current waveform diagram of the third embodiment of the output voltage and output current provided by the power unit of the power supply device of the formation system shown in the figure. In this embodiment, when the control unit 6 controls the output voltage of the power unit 3 to be in the upward voltage pulse area V2, the output current of the power unit 3 has a corresponding rising current, wherein the upward voltage pulse area V2 of this embodiment is a step type, and the multiple steps of the upward voltage pulse area V2 all have corresponding peak values, such as Fig. 7A There are two steps shown, and the step with the highest peak value in the upward voltage pulse region V2 is U max When the control unit 6 controls the output voltage of the power unit 3 to be in the downward voltage pulse region V3, the output current of the power unit 3 has a corresponding downward current, wherein the downward voltage pulse region V3 of the present embodiment is a step type, and the multiple steps of the downward voltage pulse region V3 all have corresponding valley values, for example Fig. 7A There are two steps shown, and the step with the lowest valley value in the downward voltage pulse area V3 is U min .

[0082] See also Figure 7B , which is Figure 1The voltage and current waveform diagram of the fourth embodiment of the output voltage and output current provided by the power unit of the power supply device of the formation system shown in the figure. In this embodiment, when the control unit 6 controls the output voltage of the power unit 3 to be in the upward voltage pulse area V2, the output current of the power unit 3 has a corresponding rising current, wherein the upward voltage pulse area V2 of this embodiment is a step type, and the multiple steps of the upward voltage pulse area V2 all have corresponding peak values, such as Figure 7B The single step shown, and the step with the highest peak value in the upward voltage pulse region V2 is U max When the control unit 6 controls the output voltage of the power unit 3 to be in the downward voltage pulse region V3, the output current of the power unit 3 has a corresponding downward current, wherein the downward voltage pulse region V3 of this embodiment is intermittent, for example Figure 7B The downward voltage pulse region V3 shown has two downward voltage pulses, and the voltages on both sides of each downward voltage pulse are equal to the voltage of the constant voltage region. The step with the lowest valley value in the downward voltage pulse region V3 is U min , and the constant voltage zone is between the two intermittent waveforms. Of course, in some embodiments, the control unit 6 can control the upward voltage pulse zone V2 to be intermittent, that is, the upward voltage pulse zone V2 includes multiple upward voltage pulses, and the voltages on both sides of each upward voltage pulse are equal to the voltage in the constant voltage zone. Its formation method is similar to the formation method of the downward voltage pulse zone V3, so it is not repeated here. In some embodiments, the upward current pulse zone includes multiple upward current pulses, and the currents on both sides of each upward current pulse are equal to the current in the constant current zone. In some embodiments, the downward current pulse zone includes multiple downward current pulses, and the currents on both sides of each downward current pulse are equal to the current in the constant current zone.

[0083] See also Figure 7C , which is Figure 1 The voltage and current waveform diagram of the fifth embodiment of the output voltage and output current provided by the power unit of the power supply device of the formation system shown in the figure. In this embodiment, when the control unit 6 controls the output current of the power unit 3 to be in the upward current pulse area I2, the output voltage of the power unit 3 has a corresponding rising voltage, wherein the upward current pulse area I2 of this embodiment is a step type, and the multiple steps of the upward current pulse area I2 all have corresponding peak values, such as Figure 7C There are two steps shown, and the step with the highest peak value in the upward current pulse area I2 is I max When the control unit 6 controls the output current of the power unit 3 to be in the downward current pulse area I3, the output voltage of the power unit 3 has a corresponding drop voltage, wherein the downward current pulse area I3 of the present embodiment is a step type, and the multiple steps of the downward current pulse area I3 all have corresponding valley values, for example Figure 7C There are two steps shown, and the step with the lowest valley value in the downward current pulse area I3 is I minThe multi-step or intermittent waveform can produce multiple dynamic processes of polarization, depolarization and repair, making the oxide film 8 denser and less defective, while also reducing the formation time required for the subsequent repair process, that is, reducing the power consumption per unit area.

[0084] In order to improve the dielectric quality of the barrier layer in the oxide film 8, the voltage of the upward voltage pulse region V2 includes a high-frequency ripple component, and / or the voltage of the downward voltage pulse region V3 includes a high-frequency ripple component. The electric field is periodically changed by implanting ripples to avoid impurities in the metal foil 7, thereby improving the quality of the oxide film 8. Fig. 8A , which is Figure 1 The voltage waveform diagram of the sixth embodiment of the output voltage provided by the power unit of the power supply device of the formation system shown in the figure. As shown in the figure, the voltage of the upward voltage pulse area V2 of this embodiment includes high-frequency ripple components, and each high-frequency ripple component is smaller than the peak value U of the upward voltage pulse area V2. max The voltage of the downward voltage pulse region V3 includes a high-frequency ripple component and a low-frequency ripple component, and each high-frequency ripple component is greater than the valley value U of the downward voltage pulse region V3. min , wherein the high-frequency ripple component ranges from 50 Hz to 500 kHz, and the low-frequency ripple component ranges from 0.01 Hz to 1 Hz, so as to utilize ripple stress to accelerate the dynamic repair of the oxide film 8.

[0085] Of course, in one embodiment, the voltage in the upward current pulse region I2 may also include a high-frequency ripple component, and / or the voltage in the downward current pulse region I3 may also include a high-frequency ripple component, see Figure 8B , which is Figure 1 The current waveform diagram of the seventh embodiment of the output current provided by the power unit of the power supply device shown in the figure. As shown in the figure, the voltage of the upward current pulse area I2 of this embodiment includes high-frequency ripple components, and each high-frequency ripple component is smaller than the peak value I of the upward current pulse area I2. max The voltage of the downward current pulse region I3 includes a high-frequency ripple component and a low-frequency ripple component, and each high-frequency ripple component is greater than the valley value I of the downward current pulse region I3. min , where the high-frequency ripple component ranges from 50Hz to 500kHz, and the low-frequency ripple component ranges from 0.01Hz to 1Hz. The high-frequency ripple component here simulates the high-frequency ripple stress in the real circuit where the electrolytic capacitor is located, so as to utilize the local hot spots caused by high-frequency dielectric loss to accelerate the breakdown and dissolution of the defect points, and then use the newly generated oxide film to fill the high-frequency defect parts to accelerate the dynamic repair of the oxide film 8. This can fundamentally improve the quality of the oxide film 8 to prevent the consumption of electrolyte caused by dynamic repair of the electrolytic capacitor in applications containing high-frequency ripples.

[0086] In summary, the present invention provides a power supply device and a control method thereof, which uses a control unit to control the output voltage output by the power unit to have an upward voltage pulse area, a downward voltage pulse area and a constant voltage area, or controls the output current output by the power unit to have an upward current pulse area, a downward current pulse area and a constant current area, respectively, to achieve the effect of destroying the weak area in the oxide film, slowing down the dissolution and destruction process, and regenerating and filling the metal foil in the dissolution area, thereby improving the quality of the oxide film, and then improving the capacity and service life of the aluminum electrolytic capacitor. In addition, according to the relationship that the valley value of the downward voltage pulse area (or the downward current pulse area) needs to satisfy, it can be known that the valley value of the downward voltage pulse area (or the downward current pulse area) needs to be greater than 0, and it can be ensured that the electrode polarity in the electrolytic cell will not be reversed, thereby avoiding corrosion and dissolution of the metal material constituting the cathode. The valley value of the downward voltage pulse area is much lower than the peak value of the upward voltage pulse area, and the valley value of the downward current pulse area is much lower than the peak value of the upward current pulse area, which can produce a larger local voltage and current drop effect, so as to quickly complete the depolarization and dissolution process of the oxide film, reduce the dynamic repair time, and thus reduce the energy consumption of the overall power supply device.

[0087] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A control method, applied to a power supply device, the power supply device comprising a power unit and a control unit, wherein the control method comprises: An electrolytic cell is provided, wherein an electrolyte is contained in the electrolytic cell, an anode and a cathode are arranged in the electrolyte, and a metal foil is arranged on the anode; connecting the output end of the power unit to the anode and the cathode, the power unit outputting an output voltage for forming the metal foil; and The control unit controls the power unit so that the output voltage has a constant voltage region, an upward voltage pulse region and a downward voltage pulse region, wherein the valley value of the downward voltage pulse region satisfies the following relationship: O<U min ≤V fn in, V fn is the voltage value in the constant voltage zone, U min is the valley value of the downward voltage pulse region.

2. The control method as described in claim 1, wherein the time between the starting point of the upward voltage pulse zone to the end point of the adjacent downward voltage pulse zone is between 1 and 100 seconds, or the time between the starting point of the downward voltage pulse zone to the end point of the adjacent upward voltage pulse zone is between 1 and 100 seconds.

3. The control method as claimed in claim 1, wherein the voltage in the upward voltage pulse zone is constant, curved or stepped, and / or the voltage in the downward voltage pulse zone is constant, curved or stepped.

4. The control method as described in claim 1, wherein the voltage in the upward voltage pulse zone includes a high-frequency ripple component, and / or the voltage in the downward voltage pulse zone includes a high-frequency ripple component, and the range of the high-frequency ripple component is between 50Hz and 500kHz.

5. The control method as claimed in claim 1, wherein the upward voltage pulse area includes one or more upward voltage pulses, the downward voltage pulse area includes one or more downward voltage pulses, and the upward voltage pulse area and the downward voltage pulse area are continuous.

6. The control method according to claim 1, wherein the peak value of the upward voltage pulse region satisfies the following relationship: V fn <U max ≤(1+k 1n )V fn in, U max is the peak value of the upward voltage pulse region, 2%≤k 1n ≤20%.

7. The control method as described in claim 1, wherein the upward voltage pulse zone contains one or more upward voltage pulses, the downward voltage pulse zone contains one or more downward voltage pulses, and the constant voltage zone is contained between the upward voltage pulse zone and the downward voltage pulse zone.

8. A control method, applied to a power supply device, the power supply device comprising a power unit and a control unit, wherein the control method comprises: An electrolytic cell is provided, wherein the electrolytic cell has an electrolyte, an anode and a cathode are placed in the electrolyte, and a metal foil is disposed on the anode; Connecting the output of the power unit to the anode and the cathode, the power unit outputting an output current for forming the metal foil; as well as The control unit controls the power unit so that the output current includes a constant current region, an upward current pulse region and a downward current pulse region, wherein the valley values ​​of the downward current pulse region respectively satisfy the following relationship: 0<I min ≤I fn Among them, I fn is the current value in the constant current region, I min is the valley value of the downward current pulse region.

9. The control method as described in claim 8, wherein the time between the starting point of the upward current pulse zone to the end point of the adjacent downward current pulse zone is between 1 and 100 seconds, or the time between the starting point of the downward current pulse zone to the end point of the adjacent upward current pulse zone is between 1 and 100 seconds. 10 . The control method according to claim 8 , wherein the current in the upward current pulse region is constant, curved or stepped, and / or the current in the downward current pulse region is constant, curved or stepped.

11. The control method as claimed in claim 8, wherein the current in the upward current pulse region includes a high-frequency ripple component, and / or the current in the downward current pulse region includes a high-frequency ripple component, and the range of the high-frequency ripple component is between 50 Hz and 500 kHz.

12. The control method as claimed in claim 8, wherein the upward voltage pulse area includes one or more upward voltage pulses, the downward voltage pulse area includes one or more downward voltage pulses, and the upward current pulse area and the downward current pulse area are continuous.

13. The control method according to claim 8, wherein the peak value of the upward voltage pulse region satisfies the following relationship: I fn <I max ≤(1+k 2n )I fn Among them, I max is the peak value of the upward current pulse region, 2%≤k 2n ≤20%.

14. The control method as described in claim 8, wherein the upward current pulse zone includes one or more upward current pulses, the downward current pulse zone includes one or more downward current pulses, and the constant current zone is included between the upward current pulse zone and the downward current pulse zone.

15. A formation system comprising: A power unit including at least one output terminal and outputting an output voltage; an electrolytic cell having an electrolyte; an anode disposed in the electrolyte and connected to the at least one output terminal of the power unit; a cathode disposed in the electrolyte and connected to the at least one output terminal of the power unit; a metal foil disposed on the anode to be formed according to the output voltage; as well as A control unit is connected to the power unit to control the power unit so that the output voltage has a constant voltage region, an upward voltage pulse region and a downward voltage pulse region, wherein the valley value of the downward voltage pulse region satisfies the following relationship: 0<U min ≤V fn Among them, V fn is the voltage value in the constant voltage zone, U min is the valley value of the downward voltage pulse region.

16. A chemical formation system as described in claim 15, wherein the time between the starting point of the upward voltage pulse zone to the end point of the adjacent downward voltage pulse zone is between 1 and 100 seconds, or the time between the starting point of the downward voltage pulse zone to the end point of the adjacent upward voltage pulse zone is between 1 and 100 seconds. 17 . The formation system of claim 15 , wherein the voltage in the upward voltage pulse region is constant, curved or stepped, and / or the voltage in the downward voltage pulse region is constant, curved or stepped.

18. The formation system of claim 15, wherein the voltage in the upward voltage pulse region includes a high-frequency ripple component, and / or the voltage in the downward voltage pulse region includes a high-frequency ripple component, and the high-frequency ripple component ranges from 50 Hz to 500 kHz.

19. The formation system of claim 15, wherein the upward voltage pulse zone comprises one or more upward voltage pulses, the downward voltage pulse zone comprises one or more downward voltage pulses, and the upward voltage pulse zone and the downward voltage pulse zone are continuous.

20. The formation system of claim 15, wherein the peak value of the upward voltage pulse region satisfies the following relationship: V fn <U max ≤(1+k 1n )V fn in, U max is the peak value of the upward voltage pulse region, 2%≤k 1n ≤20%.

21. The chemical formation system of claim 15, wherein the upward voltage pulse zone comprises one or more upward voltage pulses, the downward voltage pulse zone comprises one or more downward voltage pulses, and the constant voltage zone is comprised between the upward voltage pulse zone and the downward voltage pulse zone.

22. A formation system comprising: A power unit including at least one output terminal and outputting an output current; an electrolytic cell having an electrolyte; an anode disposed in the electrolyte and connected to the at least one output terminal of the power unit; a cathode disposed in the electrolyte and connected to the at least one output terminal of the power unit; a metal foil disposed on the anode to be formed according to the output current; as well as A control unit is connected to the power unit to control the power unit so that the output current has a constant current region, an upward current pulse region and a downward current pulse region, wherein the valley value of the downward current pulse region satisfies the following relationship: 0<U min ≤V fn Among them, V fn is the current value in the constant current region, U min is the valley value of the downward current pulse region.

23. A chemical formation system as described in claim 22, wherein the time between the starting point of the upward current pulse zone to the end point of the adjacent downward current pulse zone is between 1 and 100 seconds, or the time between the starting point of the downward current pulse zone to the end point of the adjacent upward current pulse zone is between 1 and 100 seconds.

24. The chemical formation system of claim 22, wherein the current in the upward current pulse zone is constant, curved or stepped, and / or the current in the downward current pulse zone is constant, curved or stepped.

25. The formation system of claim 22, wherein the current in the upward current pulse zone includes a high-frequency ripple component, and / or the current in the downward current pulse zone includes a high-frequency ripple component, and the high-frequency ripple component ranges from 50 Hz to 500 kHz.

26. The formation system of claim 22, wherein the upward voltage pulse zone comprises one or more upward voltage pulses, the downward voltage pulse zone comprises one or more downward voltage pulses, and the upward current pulse zone and the downward current pulse zone are continuous.

27. The formation system of claim 22, wherein the peak value of the upward voltage pulse region satisfies the following relationship: I fn <I max ≤(1+k 2n )I fn in, I max is the peak value of the upward current pulse region, 2%≤k 2n ≤20%.

28. A chemical formation system as described in claim 22, wherein the upward current pulse zone includes one or more upward current pulses, the downward current pulse zone includes one or more downward current pulses, and the constant current zone is included between the upward current pulse zone and the downward current pulse zone.

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