Novel LLC power supply
By connecting a capacitor regulation unit in parallel in the LLC power supply and using a control module to detect the load and dynamically adjust the resonant capacitor, the problem of fixed resonant capacitor parameters is solved, and efficient and stable power supply operation under different loads is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-26
- Publication Date
- 2026-03-27
AI Technical Summary
In existing LLC power supplies, the parameters of the resonant capacitor are fixed, making it difficult to balance efficiency and stability under different operating conditions.
A capacitor adjustment unit is connected in parallel across the resonant capacitor, and the output load of the circuit is detected by a control module. The parallel capacitor is increased when the load is light and decreased when the load is heavy. The resonant capacitor can be flexibly adjusted through the capacitor adjustment unit.
Under different load conditions, it improves the efficiency and stability of the power supply, reduces switching losses, extends the service life of the equipment, and increases hardware costs only to a limited extent.
Smart Images
Figure CN224054123U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the resonance capacitance technical field of LLC power supply, especially in a kind of novel LLC power supply. BACKGROUND
[0002] LLC power supply is a kind of switching power supply based on LLC resonant circuit, and the core of LLC power supply is the resonant loop formed by two inductances (transformer primary side leakage inductance Lr and excitation inductance Lm) and a capacitor (resonant capacitor Cr). When the switch tube is turned on and turned off at a certain frequency, resonance occurs in the resonant loop, making the current and voltage in the circuit exhibit sinusoidal characteristics. By using the characteristics that inductance current cannot change abruptly and capacitor voltage cannot change abruptly, zero-voltage turn-on (ZVS) and zero-current turn-off (ZCS) of the switch tube are realized, thereby greatly reducing switching loss. Servers usually require high-power and high-efficiency power supply, and LLC power supply can meet the requirements of servers for power supply efficiency and stability, while also effectively reducing the energy consumption and heat dissipation requirements of servers.
[0003] The resonant capacitor in LLC power supply is one of the key elements of LLC resonant circuit. During the operation of LLC circuit, the resonant capacitor cooperates with the inductor to store and release electrical energy at different stages, achieving efficient transmission and conversion of energy. Together with the transformer primary side leakage inductance (Lr) and excitation inductance (Lm), it forms a resonant loop, which resonates at a certain frequency, enabling the circuit to efficiently convert a certain DC voltage to another DC voltage value.
[0004] In existing LLC power supply, the parameters of resonant capacitor are usually fixed, so the resonant frequencies Fr1 and Fr2 are also fixed. In traditional LLC power supply, the parameters of resonant capacitor are usually fixed, which limits the performance optimization of power supply under different working conditions. For example, in light load and heavy load conditions, due to the current and voltage fluctuations caused by load changes, the resonant capacitor with fixed parameters cannot balance efficiency and stability. UTILITY MODEL CONTENTS
[0005] In existing LLC resonant power supply, the parameters of resonant capacitor are fixed, which makes it difficult to balance efficiency and stability.
[0006] To solve the above problems, a novel LLC power supply is proposed, which adjusts the resonant capacitor by connecting a capacitor adjustment unit in parallel at both ends of the resonant capacitor, and uses a control module to detect the load condition at the output end of the circuit. In light load, the parallel capacitor is increased by the capacitor adjustment unit, and in heavy load, the parallel capacitor is reduced, which realizes flexible adjustment of the resonant capacitor according to the load, and solves the problem of fixed parameters of resonant capacitor in existing LLC resonant power supply, which makes it difficult to balance efficiency and stability.
[0007] A novel LLC power supply, comprising:
[0008] input module;
[0009] resonance module;
[0010] output module;
[0011] control module;
[0012] the input module, resonance module, output module are electrically connected in sequence;
[0013] the control module is electrically connected with the output module and resonance module respectively;
[0014] wherein, the resonance module comprises:
[0015] first resonance capacitor and capacitor adjustment unit;
[0016] the first resonance capacitor and the capacitor adjustment unit are connected in parallel in the resonance module;
[0017] the capacitor adjustment unit is used for adjusting the capacitance value according to the instruction of the control module.
[0018] In a first possible implementation of the novel LLC power supply, the capacitor adjustment unit comprises:
[0019] second resonance capacitor;
[0020] relay control circuit;
[0021] switch control circuit;
[0022] the switch control circuit is electrically connected with the relay control circuit, and is used for controlling the turn-off and closure of the relay control circuit;
[0023] the relay control circuit is electrically connected with the second resonance capacitor.
[0024] In a second possible implementation of the first possible implementation of the novel LLC power supply, the relay control circuit comprises:
[0025] relay coil;
[0026] normally open contact;
[0027] the first end and the second end of the relay coil are electrically connected with the switch control circuit and input power supply respectively, the normally open contact is connected in series with the second resonance capacitor, and then is connected in parallel with the first resonance capacitor, forming a capacitor parallel circuit.
[0028] In a third possible implementation of the second possible implementation of the novel LLC power supply, the switch control circuit comprises:
[0029] The first resistance and the first triode;
[0030] The first end of the first resistance is electrically connected with the control module, the second end of the first resistance is electrically connected with the base of the first triode, the emitter of the first triode is electrically connected with the input module and grounded, and the collector of the first triode is electrically connected with the first end of the relay coil.
[0031] In combination with the third possible implementation manner of the utility model, in the fourth possible implementation manner, the resonance module further comprises:
[0032] Resonance inductance
[0033] Primary side of transformer
[0034] The first end of the resonance inductance is electrically connected with the input module, the second end of the resonance inductance is electrically connected with the first end of the capacitor parallel circuit, the second end of the capacitor parallel circuit is electrically connected with the first end of the primary side of the transformer, and the second end of the primary side of the transformer is electrically connected with the emitter of the first triode.
[0035] In combination with the fourth possible implementation manner of the utility model, in the fifth possible implementation manner, the input module comprises:
[0036] First field effect transistor and second field effect transistor
[0037] The drain of the first field effect transistor is electrically connected with an input power supply, the source of the first field effect transistor is electrically connected with the first end of the resonance inductance and the drain of the second field effect transistor, and the source of the second field effect transistor is electrically connected with the emitter of the first triode and grounded.
[0038] The gate of the first field effect transistor and the gate of the second field effect transistor are electrically connected with a level control circuit.
[0039] In combination with the fourth possible implementation manner of the utility model, in the sixth possible implementation manner, the output module comprises:
[0040] Secondary side of transformer
[0041] First diode and second diode
[0042] The anode of the first diode and the anode of the second diode are respectively electrically connected with the first end and the second end of the secondary side of the transformer, and the cathode of the first diode and the cathode of the second diode are electrically connected, and the output end of the electrically connected circuit.
[0043] In combination with the sixth possible implementation manner of the utility model, in the seventh possible implementation manner, the output module further comprises:
[0044] filtering capacitor
[0045] The first end of the filtering capacitor is electrically connected with a circuit output end, the second end is electrically connected with the secondary side of the transformer, and is grounded.
[0046] The novel LLC power supply is implemented, the capacitor adjusting unit is connected in parallel at the two ends of the resonance capacitor, the load condition of the output end of the detection circuit of the control module is detected, the parallel capacitor is increased by the capacitor adjusting unit under light load, the parallel capacitor is reduced under heavy load, flexible adjustment of the resonance capacitor according to the load is realized, and the problem that the resonance capacitor parameters of the existing LLC resonance power supply are fixed and it is difficult to consider the efficiency and stability is solved. BRIEF DESCRIPTION OF DRAWINGS
[0047] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.
[0048] Figure 1 A module structure diagram of the novel LLC power supply in the present application;
[0049] Figure 2 A circuit structure diagram of the novel LLC power supply in the present application;
[0050] Components and serial numbers:
[0051] 100-input module, 200-resonance module, 300-output module, 400-control module. DETAILED DESCRIPTION
[0052] The technical solutions in the present application will be described clearly and completely in combination with the drawings in the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.
[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more related listed items.
[0054] It is to be noted that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or indirectly on the other element with intervening elements present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or indirectly connected to the other element with intervening elements present.
[0055] It is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like, specify relative positions and orientations based on the orientations and positions shown in the drawings, and are used only for the purpose of convenience and brevity in describing the present application and its embodiments, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the application.
[0056] In addition, the terms "first", "second", "third", etc. are used only for descriptive purposes and do not necessarily indicate or imply relative importance or a quantity of the indicated technical features. Thus, features defined with "first", "second", etc. can include one or more such features explicitly or implicitly. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise expressly and specifically limited.
[0057] The existing LLC resonant power supply, wherein the resonant capacitor parameters are fixed, it is difficult to take into account the efficiency and stability.
[0058] In view of the above problems, a new LLC power supply is proposed.
[0059] As Figure 1 , Figure 1 A module structure diagram of a new LLC power supply in the utility model; a new LLC power supply, comprising an input module 100, a resonant module 200, an output module 300, a control module 400; the input module 100, the resonant module 200, the output module 300 are electrically connected in turn; the control module 400 is electrically connected with the output module 300 and the resonant module 200 respectively; wherein the resonant module 200 comprises a first resonant capacitor C1 and a capacitor adjusting unit; the first resonant capacitor C1 is connected in parallel with the capacitor adjusting unit in the resonant module 200; the capacitor adjusting unit is used for adjusting the capacitance value according to the instruction of the control module 400. By connecting the capacitor adjusting unit in parallel at both ends of the resonant capacitor, and using the control module 400 to detect the load condition of the output end VOUT of the circuit, when the load is light, the parallel capacitor is increased through the capacitor adjusting unit, when the load is heavy, the parallel capacitor is reduced, realizing flexible adjustment of the resonant capacitor according to the load, solving the problem that the resonant capacitor parameters of the existing LLC resonant power supply are fixed, it is difficult to take into account the efficiency and stability.
[0060] Further, the capacitance adjusting unit comprises a second resonant capacitor C3, a relay control circuit K3 and a switch control circuit; the switch control circuit is electrically connected with the relay control circuit K3, and is used for controlling the turn-off and turn-on of the relay control circuit K3; the relay control circuit K3 is electrically connected with the second resonant capacitor C3.
[0061] When the relay control circuit K3 is turned off, the second resonant capacitor C3 does not participate in the resonance, and when the relay control circuit K3 is turned on, the second resonant capacitor C3 is connected in parallel with the first resonant capacitor C1 and participates in the resonance together.
[0062] Further, as shown in Figure 2 , Figure 2 The utility model relates to a kind of circuit structure diagram of novel LLC power supply in the utility model;Relay control circuit K3 includes relay coil, normally open contact point;The first end and the second end of relay coil are electrically connected with switch control circuit and input power respectively, and normally open contact point is connected in series with second resonant capacitor C3, and is connected in parallel with first resonant capacitor C1, forms capacitor parallel circuit.
[0063] When relay coil is attracted after being powered, normally open contact point is closed, second resonant capacitor C3 is connected in parallel with first resonant capacitor C1, and participates in the resonance of power supply circuit together, so that the voltage and current of input power present sinusoidal characteristic, and output is exported through circuit output end VOUT.
[0064] Further, as shown in Figure 2 , switch control circuit includes first resistor R1 and first triode Q3;The first end of first resistor R1 is electrically connected with the control signal CTL of control chip of control module 400, the second end of first resistor R1 is electrically connected with the base of first triode Q3, the emitter of first triode Q3 is electrically connected with input module 100 and then grounded GND, and the collector of first triode Q3 is electrically connected with the first end of relay coil.
[0065] Control chip is also electrically connected with circuit output end VOUT, for detecting the load condition according to the size of output current and voltage.
[0066] First triode Q3 controls relay control circuit K3 according to the control signal of control module 400, when control module 400 judges load working condition by collecting power output current and voltage signal.When light load signal is detected, control chip outputs high level signal to make switch K3 conductive;When heavy load signal is detected, control chip outputs low level signal to make switch K3 break.
[0067] Further, as shown in Figure 2, the resonant module 200 further comprises a resonant inductor L1 and a primary side L2 of a transformer; a first end of the resonant inductor L1 is electrically connected with the input module 100, a second end of the resonant inductor L1 is electrically connected with a first end of a capacitor parallel circuit, a second end of the capacitor parallel circuit is electrically connected with a first end of the primary side L2 of the transformer, and a second end of the primary side L2 of the transformer is electrically connected with an emitter of a first triode Q3.
[0068] Further, as Figure 2 , the input module 100 comprises a first field effect transistor Q1 and a second field effect transistor Q2; a drain of the first field effect transistor Q1 is electrically connected with an input power supply, a source of the first field effect transistor Q1 is electrically connected with the first end of the resonant inductor L1 and a drain of the second field effect transistor Q2, a source of the second field effect transistor Q2 is electrically connected with the emitter of the first triode Q3 and then grounded GND; gates of the first field effect transistor Q1 and the second field effect transistor Q2 are electrically connected with a level control circuit.
[0069] Further, as Figure 2 , the output module 300 comprises a secondary side of a transformer, a first diode D1 and a second diode D2; anodes of the first diode D1 and the second diode D2 are respectively electrically connected with a first end and a second end of the secondary side of the transformer, cathodes of the first diode D1 and the second diode D2 are electrically connected, and then an output end VOUT of the circuit is electrically connected.
[0070] Further, as Figure 2 , the output module 300 further comprises a filter capacitor C2; a first end of the filter capacitor C2 is electrically connected with the output end VOUT of the circuit, a second end of the filter capacitor C2 is electrically connected with the secondary side of the transformer and grounded GND.
[0071] In the embodiment of the present application, the equivalent capacitance is dynamically adjusted to improve the full-load efficiency. Under different load conditions, the equivalent value of the resonant capacitor can be flexibly changed by controlling the on-off of the switch. When the load is light, the switch is closed to make the additional capacitor parallel, increase the equivalent capacitance, reduce the switching frequency, reduce the switching loss and improve the efficiency; when the load is heavy, the switch is turned off, only the main resonant capacitor is reserved, the high power transmission demand is met, and the high efficiency operation is ensured. Compared with the traditional fixed parameter resonant capacitor, the efficiency under light load and heavy load can be significantly improved.
[0072] The power supply stability is enhanced, and load changes can easily cause voltage fluctuation and current impact. The parallel mode can automatically adjust the resonant capacitor according to the load. The voltage fluctuation is reduced when the load is light, the power stability output is ensured when the load is heavy, the voltage and current abnormalities caused by load changes are effectively reduced, the service life of the power supply and the load equipment is prolonged, and the system stability is improved.
[0073] The cost-effectiveness is high, and the design only needs to add a switch, a capacitor and a simple control circuit, and the hardware cost increase is limited.
[0074] The novel LLC power supply of the utility model, through parallel capacitor adjusting unit in both ends of resonance capacitor, and using control module 400 to detect load condition of output end VOUT of circuit, when light load, through capacitor adjusting unit to increase parallel capacitor, when heavy load, reduce parallel capacitor, realized flexible adjustment of resonance capacitor according to load, solved the problem of fixed resonance capacitor parameter of existing LLC resonance power supply, difficult to consider efficiency and stability.
[0075] The above is only the preferred embodiment of the utility model, and does not limit the utility model, and any modification, equivalent replacement, improvement, etc. within the spirit and principle of the utility model should be included in the protection scope of the utility model.
Claims
1. A novel LLC power supply, characterized in that it comprises: an input module; a resonance module; an output module; a control module; the input module, resonance module, output module are electrically connected in turn; the control module is electrically connected with the output module and the resonance module respectively; wherein the resonance module comprises: a first resonant capacitor and a capacitor adjustment unit; the first resonant capacitor and the capacitor adjustment unit are connected in parallel in the resonance module; the capacitor adjustment unit is used to adjust the capacitance value according to the instruction of the control module.
2. The novel LLC power supply of claim 1, wherein, the capacitor adjustment unit comprises: a second resonant capacitor; a relay control circuit; a switch control circuit; the switch control circuit is electrically connected with the relay control circuit, used to control the off and close of the relay control circuit; the relay control circuit is electrically connected with the second resonant capacitor.
3. The novel LLC power supply of claim 2, wherein, the relay control circuit comprises: a relay coil; a normally open contact; the first end and the second end of the relay coil are electrically connected with the switch control circuit and the input power supply respectively, and the normally open contact is connected in series with the second resonant capacitor and in parallel with the first resonant capacitor, forming a capacitor parallel circuit.
4. The novel LLC power supply of claim 3, wherein, the switch control circuit comprises: a first resistor and a first triode; the first end of the first resistor is electrically connected with the control module, the second end of the first resistor is electrically connected with the base of the first triode, the emitter of the first triode is electrically connected with the input module and grounded, and the collector of the first triode is electrically connected with the first end of the relay coil.
5. The novel LLC power supply of claim 4, wherein, the resonance module further comprises: a resonant inductor; a primary side of a transformer; the first end of the resonant inductor is electrically connected with the input module, the second end of the resonant inductor is electrically connected with the first end of the capacitor parallel circuit, the second end of the capacitor parallel circuit is electrically connected with the first end of the primary side of the transformer, and the second end of the primary side of the transformer is electrically connected with the emitter of the first triode.
6. The novel LLC power supply of claim 5, wherein, the input module comprises: a first field effect transistor and a second field effect transistor; the drain of the first field effect transistor is electrically connected with the input power supply, the source of the first field effect transistor is electrically connected with the first end of the resonant inductor and the drain of the second field effect transistor, and the source of the second field effect transistor is electrically connected with the emitter of the first triode and grounded; the gates of the first field effect transistor and the second field effect transistor are electrically connected with a level control circuit.
7. The novel LLC power supply of claim 5, wherein, the output module comprises: a secondary side of a transformer; a first diode and a second diode; the anodes of the first diode and the second diode are electrically connected with the first end and the second end of the secondary side of the transformer respectively, and the cathodes of the first diode and the second diode are electrically connected and the output end of the circuit is electrically connected.
8. The novel LLC power supply of claim 6, wherein, the output module further comprises: a filter capacitor; the first end of the filter capacitor is electrically connected with the output end of the circuit, the second end is electrically connected with the secondary side of the transformer and grounded.