A power supply system output ripple noise suppression regenerative voltage system

Abstract

This invention discloses a power supply system output ripple noise suppression regenerative voltage system, relating to the field of switching power supply technology. A first rectifier module rectifies the output current of the power supply system to obtain a rectified first current; an inductor module suppresses noise and ripple generated by the AC voltage in the first current to obtain a second current; the inductor module generates mutual inductance voltage and mutual inductance current; a first filter module filters the second current and outputs a first load voltage; a second rectifier module rectifies the mutual inductance current to obtain a rectified third current; a voltage divider module flows through the third current to obtain a fourth current; a second filter module filters the fourth current and outputs a load voltage; a control module controls the load voltage to not exceed a threshold voltage; the first load voltage and the second load voltage are the power supply system output ripple noise suppression regenerative voltage. This invention reduces the generation of ripple and noise in the output voltage, keeping ripple and noise within a reasonable range and improving the stability of the output voltage.

Description

Technical Field

[0001] This invention relates to the field of switching power supply technology, and in particular to a power supply system output ripple noise suppression regenerative voltage system. Background Technology

[0002] With the continuous development of electronic and information technologies, more and more electronic devices have entered people's daily work and life, and the level of informatization in society is also increasing. Electronic devices have become an indispensable part of people's daily work and life. Among them, the power supply can be regarded as the heart of electronic devices, and it is crucial that the rated voltage of the power supply output is within the specified range, especially for precision instruments or display devices.

[0003] Thinner and lighter designs, along with increased intelligence, are major trends in the development of electronic products, and this is also true for display devices. Display devices not only require thinner and lighter designs, but also need to move towards narrower or even borderless bezels. This places increasingly higher demands on the overall product design, especially the power supply design. Requirements are placed on the power supply's input characteristics, output characteristics, protection, efficiency, electrical insulation, electromagnetic compatibility (EMC), absolute voltage regulation coefficient, and ripple voltage.

[0004] Existing switching power supplies generate output noise and switching noise during output voltage and switching power modulation processes, resulting in output voltage ripple and noise that exceed reasonable limits. ， The output voltage stability is poor. Summary of the Invention

[0005] The purpose of this invention is to provide a power supply system output ripple noise suppression regenerative voltage system. By suppressing the output noise of the switching power supply output voltage and the switching noise generated during the modulation process of the switching power supply, the output voltage ripple and noise are reduced, thereby keeping the output voltage ripple and noise within a reasonable range and improving the stability of the output voltage.

[0006] To achieve the above objectives, embodiments of the present invention provide the following solutions:

[0007] A power supply system output ripple noise suppression regenerative voltage system, wherein the power supply system provides an output voltage, the output voltage including an AC voltage; the power supply system output ripple noise suppression regenerative voltage system comprises:

[0008] The first rectifier module is connected to the first output terminal of the power system and is used to rectify the output current of the power system to obtain the rectified first current.

[0009] An inductor module is used to suppress noise and ripple generated by the AC voltage in the first current to obtain a second current; the primary input terminal of the inductor module is connected to the output terminal of the first rectifier module, and the primary output terminal of the inductor module is connected to an external load; the inductor module is also used to generate mutual inductance voltage and mutual inductance current.

[0010] The first filtering module is used to filter the second current and output the first load voltage; the input terminal of the first filtering module is connected between the primary output terminal of the inductor module and the external load, and the output terminal of the first filtering module is grounded.

[0011] The second rectifier module has its input terminal connected to the secondary output terminal of the inductor module, and is used to rectify the mutual inductance current to obtain the rectified third current; the secondary input terminal of the inductor module is grounded.

[0012] A voltage divider module, wherein the input terminal of the voltage divider module is connected to the output terminal of the second rectifier module, is used to obtain a fourth current by passing through the third current;

[0013] The second filtering module is used to filter the fourth current and output the load voltage; the input terminal of the second filtering module is connected between the output terminal of the voltage divider module and the input terminal of the control module, and the output terminal of the second filtering module is grounded.

[0014] The control module is used to control the load voltage to be no greater than a threshold voltage; the output terminal of the control module is connected to an external load; the output terminal of the control module outputs a second load voltage.

[0015] The first load voltage and the second load voltage are the output ripple noise suppression regeneration voltages of the power supply system.

[0016] Optionally, the first rectifier module includes:

[0017] The first diode is used to rectify the output current of the power supply system to obtain a rectified first current; the input terminal of the first diode is connected to the first output terminal of the power supply system; the output terminal of the first diode is connected to the primary input terminal of the inductor module.

[0018] The second rectifier module includes:

[0019] The second diode is used to rectify the mutual inductance current to obtain the rectified third current; the input terminal of the second diode is connected to the secondary output terminal of the inductor module; the output terminal of the second diode is connected to the input terminal of the voltage divider module.

[0020] Optionally, the first filtering module includes:

[0021] The first capacitor is used to perform a first filtering on the second current to obtain a filtered first voltage; the input terminal of the first capacitor is connected to the primary output terminal of the inductor module; the output terminal of the first capacitor is grounded.

[0022] The second capacitor is used to perform a second filtering on the filtered first voltage to obtain the first load voltage; the input terminal of the second capacitor is connected to the primary output terminal of the inductor module; the output terminal of the second capacitor is grounded.

[0023] The second filtering module includes:

[0024] The third capacitor is used to filter the fourth current to obtain the filtered load voltage; the input terminal of the third capacitor is connected to the output terminal of the voltage divider module; the output terminal of the third capacitor is grounded.

[0025] Optionally, the inductor module includes:

[0026] Magnetic core; the magnetic core includes: iron powder core, iron-silicon-aluminum powder core, or ferrite powder core; the temperature change of the magnetic core is directly related to the magnetic core loss; the magnetic core loss includes hysteresis loss and eddy current loss;

[0027] A coil; the coil is wound on the outer surface of the magnetic core.

[0028] Optionally, the formula for calculating the core loss is as follows:

[0029]

[0030] Among them, P core_loss (mW / cm 3 ) represents the core loss, f is the operating frequency of the switching power supply, B is the peak value of the AC magnetic flux density in one switching cycle, and a, b, c, and d are constants.

[0031] Optionally, when the peak value of the AC magnetic flux density remains constant, the maximum current ripple is generated when the peak value of the AC magnetic flux density within one switching cycle is reached.

[0032] At the moment when the maximum current ripple is generated, the instantaneous AC magnetic flux density reaches its maximum value, and the instantaneous core loss also reaches its maximum value.

[0033] Optionally, when the peak value of the AC magnetic flux density changes, the core loss generated at any moment of the peak value of the AC magnetic flux density within one switching cycle is calculated;

[0034] Calculate the average core loss based on the core loss generated at any given time.

[0035] The average core loss is used to characterize the core loss over a switching cycle.

[0036] Optionally, the coil is wound on the outer surface of the magnetic core, and the winding pattern includes: cyclic, reciprocating, or progressive.

[0037] Optionally, the value of the inductance of the inductor module is obtained based on the maximum ripple current;

[0038] At the moment when the maximum current ripple is generated, the inductance value of the inductor module is greater than or equal to 30% of the initial permeability.

[0039] In this embodiment of the invention, the output voltage includes an AC voltage, which is the cause of ripple and noise. A first rectifier module rectifies the output current of the power supply system to obtain a rectified first current. An inductor module suppresses the noise and ripple generated by the AC voltage in the first current to obtain a second current. The inductor module also generates mutual inductance voltage and mutual inductance current. A first filter module filters the second current and outputs a first load voltage. A second rectifier module rectifies the mutual inductance current to obtain a rectified third current. A voltage divider module flows through the third current to obtain a fourth current. The second filter module filters the fourth current and outputs a load voltage. A control module controls the load voltage to be no greater than a threshold voltage. The first load voltage and the second load voltage are the power supply system output ripple and noise suppression regeneration voltages. The reduced output voltage lowers the generation of ripple and noise, thereby keeping the output voltage ripple and noise within a reasonable range and improving the stability of the output voltage. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of the structure of the power system output ripple noise suppression regenerative voltage system provided in an embodiment of the present invention;

[0042] Figure 2 A detailed structural diagram of the power system output ripple noise suppression regenerative voltage system provided in an embodiment of the present invention;

[0043] Figure 3 Hysteresis loop diagram of an inductor provided in an embodiment of the present invention;

[0044] Figure 4 A schematic diagram of the DC operating point of a PFC inductor or a BOOST inductor provided in an embodiment of the present invention;

[0045] Figure 5 This is a schematic diagram of the coil winding pattern provided in an embodiment of the present invention.

[0046] Symbol explanation:

[0047] Power supply system-1, first rectifier module-2, inductor module-3, first filter module-4, external load-5, second rectifier module-6, voltage divider module-7, control module-8, external load-9, second filter module-10. Detailed Implementation

[0048] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] The purpose of this invention is to provide a power supply system output ripple noise suppression regenerative voltage system to solve the problem that existing switching power supply equipment generates output noise and switching noise during the output voltage and switching power supply modulation process, and the output voltage generates ripple and noise accordingly, resulting in output voltage ripple and noise exceeding the reasonable range and poor output voltage stability.

[0050] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0051] Figure 1 An exemplary structure of the regenerative voltage system for output ripple noise suppression described above is shown. The modules are described in detail below.

[0052] Power supply system 1 provides an output voltage, which includes AC voltage.

[0053] In one example, power system 1 can specifically be an isolation transformer. The output voltage contains some AC voltage (AC component), which is caused by ripple and noise.

[0054] Ripple is the fluctuation of the output DC voltage, which is related to the switching action of the switching power supply. During each switching process, electrical energy is "pumped" from the input to the output, forming a charging and discharging process, thus causing fluctuations in the output voltage. The fluctuation frequency is the same as the switching frequency. Ripple voltage is the peak-to-peak value between the ripple's peak and trough, and its magnitude is related to the capacitance and quality of the input and output capacitors of the switching power supply.

[0055] Noise is generated in two ways: one is by the switching power supply itself; the other is by external electromagnetic interference (EMI), which can enter the switching power supply through radiation or input through the power lines. The noise generated by the switching power supply itself is a high-frequency pulse train, caused by the sharp pulses generated during the switching on and off moments, also known as switching noise. The frequency of the noise pulses is much higher than the switching frequency, and the noise voltage is its peak-to-peak value. The amplitude of the noise voltage is largely related to the switching power supply topology, parasitic states in the circuit, and PCB design. Adding a ripple noise suppression circuit to the switching power supply can regenerate voltage without passing through the main transformer. Suppressing ripple noise improves both the power supply circuit and the application performance of the switching power supply.

[0056] The first rectifier module 2 is connected to the first output terminal of the power supply system 1. The first rectifier module 2 is used to rectify the output current of the power supply system 1 to obtain the rectified first current.

[0057] In one example, the first rectifier module 2 can specifically be a diode or a rectifier circuit. The following explanation uses a diode as an example.

[0058] The first rectifier module 2 includes:

[0059] The first diode is used to rectify the output current of the power supply system 1 to obtain the rectified first current; the input terminal of the first diode is connected to the first output terminal of the power supply system 1; the output terminal of the first diode is connected to the primary input terminal of the inductor module 3.

[0060] Please see Figure 2 The first diode can be diode D12, specifically model ES1D. The input terminal of D12 is connected to the first output terminal of the isolation transformer; the output terminal of D12 is connected to the primary input terminal 1 of inductor module 3.

[0061] The first filter module 4 is used to filter the second current and output the first load voltage; the input terminal of the first filter module 4 is connected between the primary side output terminal of the inductor module 3 and the external load 5, and the output terminal of the first filter module 4 is grounded.

[0062] In one example, the first filtering module 4 can specifically be a filter capacitor or other filters or filtering circuits. The following explanation uses the simplest structure, the filter capacitor, as an example.

[0063] The first filtering module 4 includes: a first capacitor and a second capacitor.

[0064] The first capacitor is used to perform the first filtering on the second current to obtain the filtered first voltage; the input terminal of the first capacitor is connected to the primary output terminal of the inductor module 3; the output terminal of the first capacitor is grounded.

[0065] The second capacitor is used to perform a second filtering on the filtered first voltage to obtain the first load voltage; the input terminal of the second capacitor is connected to the primary output terminal of the inductor module 3; the output terminal of the second capacitor is grounded.

[0066] Please see Figure 2 The first capacitor can be C123 (100nF, 50V), and the second capacitor can be C127 (10μF, 25V). The input terminal of C123 is connected to the primary output terminal 4 of the inductor module 3; the output terminal of C123 is grounded.

[0067] The input terminal of C127 is connected to the primary output terminal 4 of inductor module 3; the output terminal of C127 is grounded.

[0068] The input terminal of the second rectifier module 6 is connected to the secondary output terminal of the inductor module 3. The second rectifier module 6 is used to rectify the mutual inductance current to obtain the rectified third current; the secondary input terminal of the inductor module 3 is grounded.

[0069] In one example, the second rectifier module 6 can specifically be a diode or a rectifier circuit. The following explanation uses a diode as an example.

[0070] The second rectifier module 6 includes:

[0071] The second diode is used to rectify the mutual inductance current to obtain the rectified third current; the input terminal of the second diode is connected to the secondary output terminal of the inductor module 3; the output terminal of the second diode is connected to the input terminal of the voltage divider module 7.

[0072] Please see Figure 2 The second diode can be diode D9, specifically model BAV5004W. The input terminal of D9 is connected to the secondary output terminal 2 of inductor module 3; the output terminal of D9 is connected to the input terminal of voltage divider module 7.

[0073] Inductor module 3 is used to suppress noise and ripple generated by the AC voltage in the first current to obtain the second current; please refer to [link / reference]. Figure 2 The primary input 1 of the inductor module 3 is connected to the output terminal of the first rectifier module 2, and the primary output terminal 4 of the inductor module 3 is connected to an external load 5; the inductor module 3 is also used to generate mutual inductance voltage and mutual inductance current.

[0074] In one example, inductor module 3 can specifically be inductor L7 (22μH, 0.9A). Inductor L7 reduces noise ripple while generating mutual inductance voltage, meeting the requirements of low-power output loads (external load 9). The inductance of inductor L7 can be calculated based on the output.

[0075] Inductor module 3 includes: a magnetic core and a coil;

[0076] Magnetic cores include: iron powder cores, iron-silicon-aluminum powder cores, or ferrite powder cores; the temperature change of the magnetic core is directly related to the core loss; the core loss includes hysteresis loss and eddy current loss;

[0077] To ensure that the temperature rise of the magnetic core due to core loss is within the allowable range (considering the service life), the core temperature requirement is also constrained by both hysteresis loss and eddy current loss.

[0078] In one example, inductor module 3 can specifically be an energy storage inductor. The magnetic core of an energy storage inductor can be made of iron powder, iron-silicon-aluminum powder, or ferrite powder, with iron powder being the most commonly used. Iron powder cores are prone to failure due to high-temperature aging. The failure mechanism can be explained as follows: Iron powder cores are made by mixing and pressing ferromagnetic powder particles with an insulating medium, which is usually composed of a polymer-resin mixture. At high temperatures, the insulating properties gradually deteriorate, and the resistance between the ferromagnetic materials decreases, leading to increased eddy current losses in the core. These large losses result in higher temperature rises, creating positive feedback, known as the thermal runaway effect. The lifespan of the iron powder core is determined by the thermal runaway effect, which is related to temperature, operating frequency, and magnetic flux density. If the insulating medium does not deteriorate at high temperatures, the core will not experience thermal runaway; this is related to the materials and processes used and is not absolute.

[0079] The temperature rise of the magnetic core is directly related to its loss. As mentioned earlier, core loss mainly consists of hysteresis loss and eddy current loss. For powder cores, due to the high insulation resistance between magnetic materials, eddy current loss is almost negligible (but thermal runaway is caused by the increasing eddy current loss). Hysteresis loss is only related to the frequency and AC magnetic flux density (hysteresis loop area), and has little to do with the DC operating point magnetic flux density. The specific formula for calculating core loss is as follows:

[0080]

[0081] Among them, P core_loss (mW / cm 3 ) represents the core loss, f is the operating frequency of the switching power supply, B is the peak value of the AC magnetic flux density in one switching cycle, and a, b, c, and d are constants. a, b, c, and d are related to the material; common material constants are shown in Table 1 below.

[0082] The values ​​represent the magnetic ring material models from Micrometals. -8 material exhibits low core loss and good linearity under high bias conditions; it is an excellent high-frequency material and has the highest cost. (Taking -8 as an example, it is an annealed carbonyl iron powder material used in the widest bandwidth transformers from 50 to 500 MHz. It is a high-quality high-frequency material with low core loss and good linearity under high bias conditions, with a permeability of 35 μm. Types include toroidal, E-core, balun, busbar, cup-shaped, disc-shaped, EH, EM, U, planar, rectangular, sleeve, and threaded cores.)

[0083] -26 is the most popular material, a cost-effective and general-purpose material commonly used in power conversion and line filtering. -34 and -35 are inexpensive alternatives to -8, suitable for applications where high-frequency losses are not critical, and offer good linearity with high bias. Table 1 illustrates that the different materials and constant values ​​of each commonly used magnetic ring result in different core losses.

[0084] Table 1

[0085] Materiais a b c d -8 1.9×10e9 2.0×10e8 9.0×10e5 2.5×10e-14 -26 1.0×10e9 1.1×10e8 1.9×10e6 1.9×10e-13 -34 1.1×10e9 3.3×10e7 2.5×10e6 7.7×10e-14 -35 3.7×10e8 2.2×10e7 2.2×10e6 1×10e-13

[0086] When the peak value of the AC magnetic flux density remains constant, the maximum current ripple is generated when the peak value of the AC magnetic flux density reaches half of the peak value within one switching cycle.

[0087] In one example, inductor module 3 can specifically be a BUCK inductor or a DC-DC inductor. When the BUCK inductor or DC-DC inductor is operating in steady state, the pulse width is also basically stable, so the B value is easy to determine.

[0088] Calculate the core loss generated at any moment of the peak value of the AC magnetic flux density within a switching cycle when the peak value of the AC magnetic flux density changes.

[0089] Calculate the average core loss based on the core loss generated at any given time.

[0090] The average core loss is used to characterize the core loss over a switching cycle.

[0091] In one example, for a PFC inductor, BOOST topology inductor, or INV inductor, the pulse width and the B value are constantly changing, so the instantaneous loss within one power frequency cycle is also uncertain. In this case, the loss should be measured by the average value over one power frequency cycle.

[0092] The maximum current ripple occurs when the input (or output) voltage is half of the output (or input) voltage. This is also when the instantaneous AC magnetic flux density reaches its maximum, thus the instantaneous loss is also at its maximum. Based on theoretical calculations and practical verification, the following relationship holds under the worst-case conditions:

[0093] BOOST topology: Pcore_loss_avg =0.7×P core_loss_peak ;

[0094] INV section: P core_loss_avg =K×P core_loss_peak ;

[0095] K = V o-pp / 2V BUS ;

[0096] Where K is related to the INV inductance and the output voltage modulation ratio, P core_loss_avg P is the average value over one power frequency cycle. core_loss_peak V is the peak-to-peak value of one power frequency cycle. o_pp For the output peak-to-peak voltage, V BUS This represents the total voltage.

[0097] The value of the inductor in inductor module 3 is determined based on the maximum ripple current;

[0098] At the moment when the maximum current ripple is generated, the inductance value of inductor module 3 is greater than or equal to 30% of the initial permeability.

[0099] Please see Figure 3 As shown in the hysteresis loop diagram, the horizontal axis represents the magnetic field strength H, and the vertical axis represents the magnetic flux density B. When H increases, the magnetic flux density B also increases. However, after the magnetic field strength H increases to a certain extent, the increase in magnetic flux density B becomes increasingly slow until it no longer changes (the permeability u becomes smaller and smaller until it reaches zero). At this point, the magnetic material is saturated. Generally, inductors used in circuits should not be saturated (except for special applications), and their operating curve should be within the saturation curve. dc It is called the DC magnetic field strength or DC operating point.

[0100] The value of the inductor is usually determined by the maximum ripple current required by the design (usually the design specification is a percentage of the maximum ripple current).

[0101] Typically, regardless of the design, at the maximum DC operating point H dc The value of the inductance should not be lower than 30% of the initial permeability; otherwise, the inductance value will fluctuate too much and have an adverse effect on the control module 8.

[0102] In one example, for a PFC inductor or a BOOST inductor, its DC operating point corresponds to a 50Hz / 60Hz power frequency signal, and is not fixed, as follows: Figure 4 The horizontal axis represents time, and the vertical axis represents current.

[0103] At this point, the maximum ripple current percentage is defined as the ratio of the maximum ripple current to the peak inductor current at the rated input voltage. The specific calculation formula is as follows:

[0104]

[0105] L min =L Initial ×μ dc %;

[0106] Among them, I Ripple_percent The percentage of ripple current, ΔI max For the maximum ripple current, I peak_avg For the average current, L min L is the minimum inductance value. Initial μ is the initial inductance value. dc This refers to the instantaneous input voltage. Note that the DC operating point here is when the instantaneous input voltage is V. BUS The corresponding instantaneous input current at half the current.

[0107] At the same time, even under the worst conditions at the maximum DC operating point (peak value of low-voltage full-load input current), it should not be lower than 30% of the initial permeability.

[0108] In another example, the value of the INV inductor is usually determined by whether the control module 8 can reliably limit the current.

[0109] Because the INV inductor needs to withstand nonlinear impact loads such as residual current devices (RCDs) (a type of leakage current protection device), uninterruptible power supplies (UPS) typically require a crest factor ratio greater than 3:1. Considering that the actual inverter current limiting will be slightly greater than 3:1, it is usually set to 4:1. Therefore, the maximum DC operating point of the INV inductor can be set to 4:1 (4 times the effective value of the inductor current under rated load). Of course, if the crest factor specification requirements change, corresponding adjustments need to be made.

[0110] At the maximum DC operating point, the maximum DC operating point of the INV inductor should not be lower than 30% of the initial permeability; otherwise, it may cause unreliable current limiting and damage the INV switching transistor.

[0111] Once the inductance value is determined, select an appropriate magnetic core and check its specifications to obtain the inductance coefficient A. L The number of turns can be calculated using the following formula.

[0112]

[0113] Where N is the number of turns and L is the inductance.

[0114] At the moment when the maximum current ripple is generated, the instantaneous AC magnetic flux density reaches its maximum value, and the instantaneous core loss also reaches its maximum value.

[0115] The coil is wound on the outer surface of the magnetic core. Winding patterns include cyclic, reciprocating, or progressive winding. During the winding process, the feasibility of meeting the inductor's manufacturing requirements must be considered. Once the theoretical inductor design is complete, engineering implementation issues need to be addressed.

[0116] The process issues to be considered include:

[0117] (1) Can the inductor coil be wound up?

[0118] This question concerns the utilization rate of the inductor's copper window (effective winding factor). The effective conductor area is the copper window area of ​​the magnetic core. For most magnetic cores, the calculation formula for the required winding factor is as follows:

[0119]

[0120] Among them, K cu To meet the winding factor requirements, the utilization rate of inductive copper windows is highest when the winding factor requirement is approximately 40%.

[0121] (2) Coil winding mode

[0122] Please see Figure 5 The main winding methods for inductors are circular winding, reciprocating winding, or progressive winding.

[0123] The cyclic winding method involves winding the coil wires in the same direction continuously, with multiple layers of wires overlapping each other.

[0124] Advantages: Can be automatically wound by machine, with a high winding coefficient.

[0125] Disadvantages: There is almost no gap between the start and end of the winding, resulting in a large interlayer pressure difference. In high-voltage applications, this can easily lead to insulation failure of the conductor due to excessive pressure difference.

[0126] The reciprocating winding method involves winding the conductor in the opposite direction after each layer, with multiple layers of conductors overlapping each other. There is a gap between the starting and ending points.

[0127] Advantages: It can be automatically wound by machine; the start and end ends are separated by a gap, which can partially solve the problem of wire insulation failure caused by large pressure difference.

[0128] Disadvantages: The starting and ending ends of the winding are separated by a gap, and the winding coefficient is not high.

[0129] The progressive winding method involves winding the wire from the starting end to the ending end in one direction without layering the wire.

[0130] Advantages: Small voltage difference between conductors, and the start and end of the winding are separated by a gap, making it suitable for high-voltage applications.

[0131] Disadvantages: It requires manual winding, which is inefficient and costly; the winding is messy and the winding coefficient is low.

[0132] In practical applications, the winding method should be selected based on the operating voltage of the inductor. However, the progressive winding method is inefficient and costly, and should not be used unless absolutely necessary.

[0133] (3) Determination of error

[0134] Because the magnetic parameters of core materials have significant distribution errors, and the differences can be even greater between different batches or manufacturers, typically ranging from ±15% to 25%, the impact of parameter deviations must be considered during the design process. Table 2 shows the inductor design specifications.

[0135] Table 2

[0136]

[0137] Based on the circuit voltage reference, determine the inductor that conforms to the specifications, and use mutual inductance to generate additional mutual inductance voltage to improve the applicability of the circuit.

[0138] The input terminal of the voltage divider module 7 is connected to the output terminal of the second rectifier module 6. The voltage divider module 7 is used to obtain the fourth current by passing through the third current.

[0139] In one example, voltage divider module 7 can specifically be a constant current resistor R473.

[0140] The second filter module 10 is used to filter the fourth current and output the load voltage; the input terminal of the second filter module 10 is connected between the output terminal of the voltage divider module 7 and the input terminal of the control module 8, and the output terminal of the second filter module 10 is grounded.

[0141] In one example, the second filtering module 10 can specifically be a filter capacitor or other filters or filtering circuits. The following explanation uses the simplest structure, the filter capacitor, as an example.

[0142] The second filtering module 10 includes:

[0143] The third capacitor is used to filter the fourth current to obtain the filtered load voltage; the input terminal of the third capacitor is connected to the output terminal of the voltage divider module 7; the output terminal of the third capacitor is grounded.

[0144] Please see Figure 2 The third capacitor can be capacitor C121 (100nF, 50V). The input terminal of C121 is connected to the output terminal of voltage divider module 7; the output terminal of C121 is grounded.

[0145] Control module 8 is used to control the load voltage to be no greater than the threshold voltage; the output terminal of control module 8 is connected to the external load 9; the output terminal of control module 8 outputs the second load voltage.

[0146] In one example, control module 8 includes at least an optocoupler and a switching transistor;

[0147] The control module 8 achieves the switching frequency of the isolation control switch by adjusting the light emission of the optocoupler, thereby stabilizing the rated range of the second load voltage.

[0148] The first load voltage and the second load voltage are the power system output ripple noise suppression regeneration voltages.

[0149] In summary, fluctuations in the input AC voltage and changes in the external load both necessitate a stable voltage output from the switching power supply. The voltage is divided by the voltage divider module 7 via the mutual inductance voltage (sampled voltage feedback), and then controlled by the control module 8 to adjust the optocoupler's emission level, thereby isolating and controlling the switching frequency of the switching transistor to ensure a stable output load voltage within the rated range. To address the issue of output voltage ripple noise not meeting the required output range, an inductor module 3 is added to the circuit, utilizing its DC-passing and AC-isolation characteristics to suppress noise ripple.

[0150] While using inductor module 3 to suppress ripple noise, another set of voltages is generated by winding the coil of inductor module 3 and utilizing the mutual inductance principle, which can be used to output a second load voltage (for small loads). This design regenerates the voltage after suppressing ripple noise on a single path of the first load voltage (output main voltage). By suppressing the output noise of the switching power supply and the switching noise generated during the modulation process, the ripple and noise of the output voltage are reduced, thus keeping the output voltage ripple and noise within a reasonable range and improving the stability of the output voltage. This design is suitable for AC to DC switching power supplies.

[0151] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0152] This document uses specific examples to illustrate the principles and implementation methods of the embodiments of the present invention. The descriptions of the embodiments above are only for the purpose of helping to understand the methods and core ideas of the embodiments of the present invention. At the same time, for those skilled in the art, there will be changes in specific implementation methods and application scope based on the ideas of the embodiments of the present invention. In summary, the content of this specification should not be construed as a limitation on the embodiments of the present invention.

Claims

1. A power supply system output ripple noise suppression regenerative voltage system, characterized in that, The power supply system provides an output voltage, which includes an AC voltage; the power supply system outputs a ripple noise suppression regenerative voltage system comprising: The first rectifier module is connected to the first output terminal of the power system and is used to rectify the output current of the power system to obtain the rectified first current. An inductor module is used to suppress noise and ripple generated by the AC voltage in the first current to obtain a second current; the primary input terminal of the inductor module is connected to the output terminal of the first rectifier module, and the primary output terminal of the inductor module is connected to an external load; the inductor module is also used to generate mutual inductance voltage and mutual inductance current. The inductor module includes: Magnetic core; the magnetic core includes: iron powder core, iron-silicon-aluminum powder core, or ferrite powder core; the temperature change of the magnetic core is directly related to the magnetic core loss; the magnetic core loss includes hysteresis loss and eddy current loss; The specific formula for calculating the core loss is as follows: ； Among them, P core_loss (mW / cm 3 ) represents the core loss, f represents the operating frequency of the switching power supply, B represents the peak value of the AC magnetic flux density in one switching cycle, and a, b, c, and d are constants. When the peak value of the AC magnetic flux density remains constant, the maximum current ripple is generated when the peak value of the AC magnetic flux density within one switching cycle is half of the peak value. At the moment when the maximum current ripple is generated, the instantaneous AC magnetic flux density reaches its maximum value, and the instantaneous core loss also reaches its maximum value. Coil; the coil is wound on the outer surface of the magnetic core; The first filtering module is used to filter the second current and output the first load voltage; the input terminal of the first filtering module is connected between the primary output terminal of the inductor module and the external load, and the output terminal of the first filtering module is grounded. The second rectifier module has its input terminal connected to the secondary output terminal of the inductor module, and is used to rectify the mutual inductance current to obtain the rectified third current; the secondary input terminal of the inductor module is grounded. A voltage divider module, wherein the input terminal of the voltage divider module is connected to the output terminal of the second rectifier module, is used to obtain a fourth current by passing through the third current; The second filtering module is used to filter the fourth current and output the load voltage; the input terminal of the second filtering module is connected between the output terminal of the voltage divider module and the input terminal of the control module, and the output terminal of the second filtering module is grounded. The control module is used to control the load voltage to be no greater than a threshold voltage; the output terminal of the control module is connected to an external load; the output terminal of the control module outputs a second load voltage. The first load voltage and the second load voltage are the output ripple noise suppression regeneration voltages of the power supply system.

2. The power supply system output ripple noise suppression regenerative voltage system according to claim 1, characterized in that, The first rectifier module includes: The first diode is used to rectify the output current of the power supply system to obtain a rectified first current; the input terminal of the first diode is connected to the first output terminal of the power supply system; the output terminal of the first diode is connected to the primary input terminal of the inductor module. The second rectifier module includes: The second diode is used to rectify the mutual inductance current to obtain the rectified third current; the input terminal of the second diode is connected to the secondary output terminal of the inductor module; the output terminal of the second diode is connected to the input terminal of the voltage divider module.

3. The power supply system output ripple noise suppression regenerative voltage system according to claim 1, characterized in that, The first filtering module includes: The first capacitor is used to perform a first filtering on the second current to obtain a filtered first voltage; the input terminal of the first capacitor is connected to the primary output terminal of the inductor module; the output terminal of the first capacitor is grounded. The second capacitor is used to perform a second filtering on the filtered first voltage to obtain the first load voltage; the input terminal of the second capacitor is connected to the primary output terminal of the inductor module; the output terminal of the second capacitor is grounded. The second filtering module includes: The third capacitor is used to filter the fourth current to obtain the filtered load voltage; the input terminal of the third capacitor is connected to the output terminal of the voltage divider module; the output terminal of the third capacitor is grounded.

4. The power supply system output ripple noise suppression regenerative voltage system according to claim 1, characterized in that, When the peak value of the AC magnetic flux density changes, calculate the core loss generated at any moment of the peak value of the AC magnetic flux density within one switching cycle; Calculate the average core loss based on the core loss generated at any given time. The average core loss is used to characterize the core loss over a switching cycle.

5. The power supply system output ripple noise suppression regenerative voltage system according to claim 1, characterized in that, The coil is wound on the outer surface of the magnetic core, and the winding pattern includes: cyclic, reciprocating or progressive.

6. The power supply system output ripple noise suppression regenerative voltage system according to claim 1, characterized in that, The inductance value of the inductor module is obtained based on the maximum ripple current; At the moment when the maximum current ripple is generated, the inductance of the inductor module is greater than or equal to 30% of the initial permeability.

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