Power supply circuit, power supply control method, composite power supply circuit and electronic equipment

Abstract

The present application discloses a power supply circuit, a power supply control method, a composite power supply circuit and an electronic device, wherein the power supply circuit includes: an inverter circuit, which converts a first DC signal of a DC power supply into a first AC signal; a resonant circuit, which adjusts the first AC signal; an isolation transformer, which converts the adjusted first AC signal into a second AC signal; a rectifier circuit, which converts the second AC signal into a second DC signal and outputs it to a load circuit; a control circuit, which generates a first control signal based on the rise and / or fall of the voltage of the first AC signal or the second AC signal; and a rectifier circuit that adjusts the second DC signal using the first control signal. In the above manner, the power supply circuit of the present application effectively ensures the realization of zero voltage switching of the inverter circuit, thereby ensuring high efficiency and high reliability in the full frequency working range, and effectively reduces circuit loss and switching noise, widens the maximum gain range of the rectifier circuit, and facilitates a wider range of applications.

Description

Technical Field

[0001] The present application relates to the field of power supply technology, and in particular to a power supply circuit, a power supply control method, a composite power supply circuit and an electronic device. Background Art

[0002] With the vigorous development of various electronic products, especially the advent of the cloud computing and big data era, the use of servers has increased dramatically, which has put forward higher requirements for high-efficiency, high-power density and low-noise power supply systems. In the power supply system, PWM (Pulse width modulation) converters are generally used to achieve power control.

[0003] However, traditional PWM converters face bottlenecks in improving overall efficiency and power density due to the complexity of soft-opening implementation, large circuit losses and switching noise. Summary of the invention

[0004] The main technical problem solved by the present application is to provide a power supply circuit, a power supply control method, a composite power supply circuit and an electronic device, which can solve the problems in the prior art that the circuit loss and switching noise of the power supply circuit are large, and there are bottlenecks in improving the efficiency of the whole machine and the power density.

[0005] In order to solve the above technical problems, a technical solution adopted in the present application is: to provide a power supply circuit, wherein the power supply circuit includes: an inverter circuit, which is used to couple with a DC power supply to receive a first DC signal sent by the DC power supply and convert the first DC signal into a first AC signal; a resonant circuit, which is coupled with the inverter circuit, to receive and adjust the first AC signal sent by the inverter circuit; an isolation transformer, which is coupled with the resonant circuit, to receive the adjusted first AC signal sent by the resonant circuit, and convert the adjusted first AC signal into a second AC signal; a rectifier circuit, which is coupled with the isolation transformer and is used to couple with a load circuit to receive a second AC signal sent by the isolation transformer, and convert the second AC signal into a second DC signal to output to the load circuit; a control circuit, which is coupled with the inverter circuit and the rectifier circuit, and the control circuit samples and obtains the first AC signal and / or the second AC signal in the isolation transformer to generate a first control signal based on the rise and / or fall of the first AC signal voltage, and / or the rise and / or fall of the second AC signal voltage; the rectifier circuit is used to receive the first control signal and adjust the second DC signal based on the first control signal.

[0006] Among them, the control circuit is also used to sample and obtain the second DC signal in the rectifier circuit, compare the second DC signal with a preset power supply threshold, determine the signal frequency of the second control signal, and send the second control signal according to the signal frequency; the inverter circuit is used to receive the second control signal and adjust the first AC signal based on the second control signal.

[0007] Among them, the inverter circuit includes a first switch subcircuit and a second switch subcircuit, the first switch subcircuit is coupled to the second switch subcircuit, the resonant circuit, the isolation transformer and the control circuit, and is used to couple with the DC power supply, the second switch subcircuit is coupled to the control circuit, and the second control signal includes a first drive signal and a second drive signal; wherein, the first switch subcircuit is used to receive the first drive signal to change the switch state under the action of the first drive signal; the second switch subcircuit is used to receive the second drive signal to change the switch state under the action of the second drive signal, and cooperate with the switch state of the first switch subcircuit to adjust the first AC signal.

[0008] Among them, the control circuit includes a sampling circuit, a signal processing circuit and a driving circuit, the sampling circuit is coupled to the isolation transformer and the signal processing circuit, the signal processing circuit is coupled to the driving circuit, and the driving circuit is coupled to the inverter circuit and the rectifier circuit; the sampling circuit samples and obtains the first AC signal and / or the second AC signal in the isolation transformer; the signal processing circuit is used to receive the rise and / or fall of the first AC signal voltage, and / or the second AC signal, and in response to the rise and / or fall of the first AC signal or the second AC signal voltage, control the driving circuit to change the level state of the first control signal, and send the first control signal to the rectifier circuit to trigger the rectifier circuit to change the switch state and adjust the second DC signal.

[0009] Wherein, the control circuit also includes a first proportional filter correction circuit and a second proportional filter correction circuit, and the sampling circuit includes a first sampling circuit and a second sampling circuit, the first sampling circuit is coupled to the isolation transformer and the first proportional filter correction circuit, and the second sampling circuit is coupled to the rectifier circuit and the second proportional filter correction circuit; wherein, the first sampling circuit is used to sample and obtain the first AC signal and / or the second AC signal in the isolation transformer; the second sampling circuit is used to sample and obtain the second DC signal in the rectifier circuit; the first proportional filter correction circuit receives the first AC signal and / or the second AC signal, and compares, filters, and corrects the first AC signal and / or the second AC signal with a reference value in sequence, and then sends it to the signal processing circuit, so that the signal processing circuit controls the drive circuit to generate a third drive signal and a fourth drive signal accordingly; the second proportional filter correction circuit receives the second DC signal, and compares, filters, and corrects the second DC signal with a reference value in sequence, and then sends it to the signal processing circuit, so that the signal processing circuit controls the drive circuit to generate a first drive signal and a second drive signal accordingly.

[0010] Wherein, the rectifier circuit includes a third switch subcircuit and a fourth switch subcircuit, the isolation transformer includes a primary winding and a secondary winding, the primary winding is coupled to the resonant circuit and coupled to the secondary winding, the secondary winding is coupled to the third switch subcircuit, the fourth switch subcircuit and the sampling circuit, the third switch subcircuit is coupled to the fourth switch subcircuit and the control circuit, and is used to couple with the load circuit, the fourth switch subcircuit is coupled to the control circuit, the first control signal includes a third drive signal and a fourth drive signal, the second AC signal includes a first current signal flowing through the third switch subcircuit and a second current signal flowing through the fourth switch subcircuit; wherein, the primary winding is used to receive the regulated first AC signal sent by the resonant circuit, and transmit the first AC signal to the second current signal through the secondary winding. An AC signal is converted into a second AC signal to be sent to a third switch sub-circuit and a fourth switch sub-circuit; the first AC signal includes a first voltage signal at both ends of the primary winding, and the second AC signal includes a second voltage signal at both ends of the secondary winding; the third switch sub-circuit is used to receive a third drive signal sent by the control circuit, and the third drive signal changes the level state when the first voltage signal rises and falls, and / or the second voltage signal rises and falls, so as to trigger the third switch sub-circuit to change the switch state; the fourth switch sub-circuit is used to receive a fourth drive signal, and the fourth drive signal changes the level state when the first voltage signal rises and falls, and / or the second voltage signal rises and falls, so as to trigger the fourth switch sub-circuit to change the switch state.

[0011] Wherein, the second AC signal also includes a first current signal flowing through the third switch sub-circuit and a second current signal flowing through the fourth switch sub-circuit; when the control circuit determines that the first voltage signal and / or the second voltage signal rises, the control circuit adjusts the third drive signal from the first level state to the second level state, and when the first voltage signal and / or the second voltage signal drops, or the first current signal decays positively to 0, the third drive signal is adjusted from the second level state to the first level state; when the control circuit determines that the first voltage signal and / or the second voltage signal drops, the control circuit adjusts the fourth drive signal from the first level state to the second level state, and when the first voltage signal and / or the second voltage signal rises, or the second current signal decays positively to 0, the fourth drive signal is adjusted from the second level state to the first level state.

[0012] Wherein, the signal frequency is less than the resonant frequency of the resonant circuit, in the stage where the first drive signal is in the second level state, the second drive signal is in the first level state, the third drive signal is in the first level state, and the fourth drive signal is in the second level state; and / or, in the stage where the first drive signal is in the first level state, the second drive signal is in the second level state, the third drive signal is in the second level state, and the fourth drive signal is in the first level state, the third current flowing through the resonant circuit maintains non-inversion.

[0013] Wherein, the first switch subcircuit includes a first switch tube and a fourth switch tube, and the second switch subcircuit includes a second switch tube and a third switch tube; wherein, the first end of the first switch tube is coupled to the first end of the third switch tube and is used to couple with the first end of the DC power supply, the second end of the first switch tube is coupled to the first end of the second switch tube and the first end of the resonant circuit, the second end of the third switch tube is coupled to the first end of the fourth switch tube and the second end of the isolation transformer, the second end of the second switch tube is coupled to the second end of the fourth switch tube and is used to couple with the second end of the DC power supply, and the third end of each of the first switch tube, the second switch tube, the third switch tube and the fourth switch tube is coupled to the control output end of the control circuit; or, the first switch subcircuit includes a seventh switch tube, and the second switch subcircuit includes an eighth switch tube; wherein, the first end of the seventh switch tube is used to couple with the first end of the DC power supply, the second end of the seventh switch tube is coupled to the first end of the eighth switch tube and the first end of the resonant circuit, the second end of the eighth switch tube is coupled to the second end of the isolation transformer, and is used to couple with the second end of the DC power supply, and the third end of the seventh switch tube and the third end of the eighth switch tube are coupled to the control output end of the control circuit.

[0014] Wherein, the secondary winding includes a first sub-secondary winding and a second sub-secondary winding, the third switch sub-circuit includes a fifth switch tube, and the fourth switch sub-circuit includes a sixth switch tube; wherein, the first end of the first sub-secondary winding is coupled to the first end of the fifth switch tube, the second end of the first sub-secondary winding is coupled to the second end of the second sub-secondary winding, and is used to couple with the second end of the load circuit, the first end of the second sub-secondary winding is coupled to the first end of the sixth switch tube, the second end of the fifth switch tube is coupled to the second end of the sixth switch tube, and is used to couple with the first end of the load circuit, and the third end of the fifth switch tube and the third end of the sixth switch tube are coupled to the control output end of the control circuit; or, the third switch sub-circuit includes The ninth switch tube and the twelfth switch tube, the fourth switch sub-circuit includes the tenth switch tube and the eleventh switch tube; wherein, the first end of the secondary winding is coupled to the first end of the ninth switch tube and the second end of the tenth switch tube, the second end of the secondary winding is coupled to the first end of the eleventh switch tube and the second end of the twelfth switch tube, the second end of the ninth switch tube is coupled to the second end of the eleventh switch tube, and is used to couple with the first end of the load circuit, the first end of the tenth switch tube is coupled to the first end of the twelfth switch tube, and is used to couple with the second end of the load circuit, and the third end of each of the ninth switch tube, the tenth switch tube, the eleventh switch tube and the twelfth switch tube is coupled to the control output end of the control circuit.

[0015] To solve the above technical problems, another technical solution adopted in the present application is: to provide a power supply control method, which includes: receiving a first DC signal sent by an external DC power supply; converting the first DC signal into a first AC signal; adjusting the first AC signal; converting the adjusted first AC signal into a second AC signal; converting the second AC signal into a second DC signal to output to an external load circuit; generating a first control signal based on the rise and / or fall of the adjusted first AC signal voltage, and / or the rise and / or fall of the second AC signal voltage; and adjusting the second DC signal using the first control signal.

[0016] Among them, after the step of converting the second AC signal into a second DC signal for output to the external load circuit, it also includes: comparing the second DC signal with a preset power supply threshold to determine the signal frequency of the second control signal; and using the second control signal to adjust the first AC signal.

[0017] Among them, the first control signal includes a third drive signal and a fourth drive signal, the second AC signal includes a first voltage signal, a second voltage signal, a first current signal and a second current signal, and the step of generating the first control signal based on the rise and / or fall of the adjusted first AC signal voltage, and / or the rise and / or fall of the second AC signal voltage includes: when the first voltage signal or the second voltage signal rises, the third drive signal is adjusted from the first level state to the second level state; when the first voltage signal and / or the second voltage signal falls, or the first current signal decays positively to 0, the third drive signal is adjusted from the second level state to the first level state; when the first voltage signal and / or the second voltage signal falls, the fourth drive signal is adjusted from the first level state to the second level state; when the first voltage signal and / or the second voltage signal rises, or the second current signal decays positively to 0, the fourth drive signal is adjusted from the second level state to the first level state.

[0018] In order to solve the above technical problems, another technical solution adopted in the present application is: to provide a composite power supply circuit, wherein the composite power supply circuit includes a DC power supply and at least two power supply circuits, and the at least two power supply circuits are connected in series or in parallel with each other and coupled to the DC power supply; wherein the power supply circuit is a power supply circuit as described in any of the above items.

[0019] To solve the above technical problems, another technical solution adopted in the present application is: to provide an electronic device, wherein the electronic device includes a shell and a power supply circuit or a composite power supply circuit connected to the shell; wherein the power supply circuit is a power supply circuit as described in any one of the above items, or a composite power supply circuit as described above.

[0020] The beneficial effects of the present application are as follows: different from the prior art, the inverter circuit in the power supply circuit provided by the present application receives a first DC signal sent by a DC power supply, and converts the first DC signal into a first AC signal, so as to adjust the first AC signal by using a resonant circuit, the isolation transformer converts the adjusted first AC signal into a second AC signal, and the rectifier circuit converts the second AC signal into a second DC signal, so as to output it to the load circuit; wherein, the control circuit generates a first control signal based on the rise and / or fall of the voltage of the first AC signal or the second AC signal, and sends the first control signal to the rectifier circuit, so as to trigger the rectifier circuit to change the switch state under the action of the first control signal, so as to adjust the second DC signal, and adjust the current flowing through the resonant circuit through the isolation transformer, thereby effectively ensuring the realization of the ZVS (Zero Voltage Switch) of the inverter circuit, so as to ensure the high efficiency and high reliability of the power supply circuit in the full frequency working range, thereby effectively reducing the circuit loss and switching noise, widening the maximum gain range of the power supply circuit, and improving the overall efficiency and power density of the power supply circuit, so as to facilitate a wider range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0022] Figure 1 It is a structural schematic diagram of the first embodiment of the power supply circuit of the present application;

[0023] Figure 2 is a structural schematic diagram of a second embodiment of the power supply circuit of the present application;

[0024] Figure 3a yes Figure 2 Equivalent circuit diagram of the resonant circuit in working mode 1;

[0025] Figure 3b yes Figure 2 Equivalent circuit diagram of the resonant circuit in working mode 2;

[0026] Figure 3c yes Figure 2 Equivalent circuit diagram of the resonant circuit in working mode 3;

[0027] Figure 3d yes Figure 2 Equivalent circuit diagram of the resonant circuit in working mode 4;

[0028] Figure 4a yes Figure 2 A schematic diagram of waveforms of each sampling signal and a control signal when the signal frequency of the second control signal given by the control circuit is greater than the resonant frequency of the resonant circuit;

[0029] Figure 4b yes Figure 2 A schematic diagram of waveforms of each sampling signal and control signal when the signal frequency of the second control signal given by the control circuit is equal to the resonant frequency of the resonant circuit;

[0030] Figure 4c yes Figure 2 A schematic diagram of waveforms of each sampling signal and a control signal when the signal frequency of the second control signal given by the control circuit is less than the resonant frequency of the resonant circuit;

[0031] Figure 5 yes Figure 2 A schematic structural diagram of another embodiment of an inverter circuit in a power supply circuit;

[0032] Figure 6 yes Figure 2 A schematic structural diagram of another embodiment of a rectifier circuit in a power supply circuit;

[0033] Figure 7 It is a flow chart of an implementation method of a power supply control method of the present application;

[0034] Figure 8 yes Figure 7 A schematic diagram of a flow chart of an embodiment of step S36;

[0035] Fig. 9 It is a schematic diagram of a framework of an implementation method of a composite power supply circuit of the present application;

[0036] Fig.10 It is a schematic diagram of the framework of an implementation scheme of the electronic device of the present application. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0038] The terms "first", "second" and "third" in this application are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second" and "third" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. All directional indications (such as up, down, left, right, front, back...) in the implementation mode of this application are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0039] Reference to "embodiment" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0040] The present application is described in detail below with reference to the accompanying drawings and implementation methods.

[0041] See also Figure 1 , Figure 1 1 is a schematic diagram of the structure of the first embodiment of the power supply circuit of the present application. In this embodiment, the power supply circuit 10 includes: an inverter circuit 11, a resonant circuit 12, an isolation transformer 13, a rectifier circuit 14 and a control circuit 15.

[0042] Among them, a power supply circuit 10 provided in the present application is specifically used in the power supply of a load circuit 102 that requires a DC output, so as to utilize the DC power provided by an external DC power supply 101, convert the DC power into AC power, and then convert it back into DC power to provide it to any reasonable electronic device that has higher requirements for high efficiency, high power density, and low noise, such as a server, a computer, an intelligent communication device, etc. The load circuit 102 is not limited to this in this embodiment.

[0043] It is worth noting that the DC power supply 101 can be specifically understood as a battery with a DC output, a DC voltage regulator or any other DC power source, or a DC power supply output after power conversion and regulation of a grid power supply, a photovoltaic power supply, an independent generator or any other reasonable upper power supply. The load circuit 102 can be understood as a signal function circuit that operates using the DC output of the power supply circuit 10.

[0044] In addition, the term "coupled" herein refers to any direct and indirect connection means. Therefore, if the first circuit is described as being coupled to the second circuit, it means that the first circuit can be directly connected to the second circuit through electrical connection or signal connection methods such as wireless transmission, optical transmission, etc., or can be indirectly connected to the second circuit through other circuits or connection means.

[0045] Specifically, the inverter circuit 11 is used to achieve physical and electrical connection with an external DC power supply 101 to receive a first DC signal with a constant current and / or voltage provided by the DC power supply 101, and utilize its internal switching action mechanism, such as the opening and closing action mechanism of switching devices such as IGBT (Insulated Gate Bipolar Transistor), high-frequency transistor, MOS (Metal Oxide Semiconductor Field Effect Transistor), etc., to quickly switch the DC power under signal control to generate an alternating voltage waveform and obtain a first AC signal.

[0046] Among them, the resonant circuit 12 is directly connected to the inverter circuit 11 to receive the first AC signal sent by the inverter circuit 11, and perform one or more of any reasonable signal adjustments such as filtering, shaping, phase shifting, etc. on the first AC signal, in order to achieve better output characteristics and ensure that subsequent links, such as rectifier circuits or loads, obtain more stable and efficient electrical energy.

[0047] The isolation transformer 13 is coupled to the resonant circuit 12 to receive the regulated first AC signal sent by the resonant circuit 12, and converts the regulated first AC signal into a second AC signal, so as to adopt electromagnetic connection instead of electrical connection, so as to realize the primary and secondary side electrical isolation and voltage matching, and meet the primary and secondary side electrical safety insulation requirements.

[0048] The rectifier circuit 14 is coupled to the isolation transformer 13 and is used to couple with the external load circuit 102, and specifically involves transformer isolation and rectification. Specifically, the rectifier circuit 14 receives the second AC signal sent by the isolation transformer 13, and uses a high-frequency rectification technology, such as PWM, synchronous rectification, reverse damping rectification, and any other reasonable rectification methods, to obtain a stable DC output, that is, a second DC signal, using the second AC signal to output to the load circuit 102 to meet the power usage of the load circuit 102.

[0049] The control circuit 15 is electrically and / or communicatively connected to the inverter circuit 11 and the rectifier circuit 14 to adjust the switching state of the inverter circuit 11 and the rectifier circuit 14 , thereby adjusting the signal output of the inverter circuit 11 and the rectifier circuit 14 .

[0050] Specifically, the control circuit 15 samples the first AC signal and / or the second AC signal from the isolation transformer 13 to generate a first control signal based on the rise and / or fall of the first AC signal voltage and / or the rise and / or fall of the second AC signal voltage.

[0051] It is worth noting that the first AC signal can be understood as the voltage and current signals of the primary side of the isolation transformer 13, and the second AC signal can be understood as the voltage and current signals of the secondary side of the isolation transformer 13, that is, the voltage of the first AC signal and the voltage of the second AC signal will rise or fall synchronously. Therefore, the sampling of the voltage changes of the first AC signal and the second AC signal by the control circuit 15 is essentially the same, both of which are for sampling the voltage changes on the winding of the isolation transformer 13. You can choose one of them. In order to ensure the stability and effectiveness of the sampling results and to facilitate mutual verification, you can also sample both.

[0052] In addition, the rise and / or fall of the above-mentioned first AC signal voltage refers to the existence of two states of rising and falling in the first AC signal, that is, the voltage waveform of the first AC signal has a rising edge and a falling edge, but not the rise and fall of the first AC signal voltage at the same time; similarly, the rise and / or fall of the above-mentioned second AC signal voltage refers to the existence of two states of rising and falling in the second AC signal, or the second AC signal has two voltage signals, both of which have two states of rising and falling, and when one of the voltage signals rises, the other falls, and when one of the voltage signals falls, the other rises; it can be understood that the control circuit 15 specifically generates a first control signal in response to one or more states of the rise of the first AC signal voltage, the fall of the first AC signal voltage, the rise of the second AC signal voltage and the fall of the second AC signal voltage, and the present application does not limit this.

[0053] The rectifier circuit 14 is also used to receive the first control signal sent by the control circuit 15, so as to change the switch state under the action of the first control signal to adjust the second DC signal, and in turn adjust the current flowing through the resonant circuit 12 through the isolation transformer 13. For example, before the switch state of the inverter circuit 11 is triggered to change, the current flowing through the resonant circuit 12 is maintained without changing phase to ensure the realization of ZVS opening and closing of the inverter circuit.

[0054] Optionally, the control circuit 15 may specifically include a control chip, an MCU (Micro Controller Unit) circuit, a CPU (Central Processing Unit), a single-chip microcomputer, a field programmable gate array, a programmable logic device, a discrete gate or transistor logic device, discrete hardware, and any other reasonable circuit unit with a signal processing function, and the present application does not limit this.

[0055] The above scheme adjusts the switching state of the rectifier circuit 14 in response to the voltage change of the first AC signal and / or the second AC signal, thereby effectively ensuring that the inverter circuit 11 achieves ZVS opening, so as to ensure the high efficiency and high reliability of the power supply circuit 10 in the full frequency operating range, thereby effectively reducing circuit losses and switching noise, widening the maximum gain range of the power supply circuit 10, and improving the overall efficiency and power density of the power supply circuit 10, which is convenient for a wider range of applications.

[0056] It is worth mentioning that ZVS turn-on is a soft switching technology commonly used in switching power supplies. It achieves zero voltage turn-on by reducing the voltage to zero before the switch tube is turned on, so as to reduce switching losses and electromagnetic interference.

[0057] In one embodiment, the control circuit 15 is also used to sample and obtain a second DC signal output to the load circuit 102 from the rectifier circuit 14, so as to compare the currently obtained second DC signal with a preset power supply threshold, and determine the signal frequency of the second control signal based on the comparison difference between the second DC signal and the preset power supply threshold, and then send the second control signal to the inverter circuit 11 according to the currently determined signal frequency, triggering the inverter circuit 11 to adjust its switching state, so as to adjust the first AC signal corresponding to the output of the inverter circuit 11, and then adjust the second DC signal.

[0058] It is worth noting that the second DC signal includes a current signal and a voltage signal, and the preset power supply threshold can be specifically understood as the target power supply demand of the load circuit 102, such as the target setting value of the voltage, current or power of the power supply output currently required by the load circuit 102, which can also be understood as the preset target power supply signal. The control circuit 15 specifically uses the difference between the second DC signal and the preset power supply threshold to dynamically adjust the signal frequency of the second control signal. For example, when it is determined that the second DC signal is less than the preset power supply threshold, the current signal frequency of the second control signal is increased, and when it is determined that the second DC signal is greater than the preset power supply threshold, the current signal frequency of the second control signal is decreased until the second DC signal is adjusted to the target setting value of the voltage, current or power, that is, within the range of the preset power supply threshold, and the signal frequency of the second control signal currently in a stable state is determined.

[0059] It is understandable that the control circuit 15 not only optimizes the control efficiency of the inverter circuit 11 through precise frequency matching, but also ensures the frequency stability of the resonant oscillation circuit and the realization of ZVS opening and closing of the inverter circuit 11, thereby effectively ensuring the efficient and stable power supply performance of the entire power supply circuit 10.

[0060] See also Figure 2 , Figure 2 The power circuit in this embodiment differs from the first embodiment of the power circuit provided in this application in that the inverter circuit 21 in the power circuit 20 further includes a first switch subcircuit 211 and a second switch subcircuit 212 .

[0061] Specifically, the first switch sub-circuit 211 is coupled to the second switch sub-circuit 212 , the resonant circuit 22 , the isolation transformer 23 and the control circuit 25 , and is used to couple to the DC power supply 101 . The second switch sub-circuit 212 is coupled to the control circuit 25 .

[0062] Among them, the second control signal further includes a first drive signal PWMA and a second drive signal PWMB, and the first drive signal PWMA and the second drive signal PWMB are in opposite phases, that is, the level states of the two are opposite. When the first drive signal PWMA is in the first level state, the second drive signal PWMB is in the second level state; when the first drive signal PWMA is in the second level state, the second drive signal PWMB is in the first level state; and the signal frequencies of the first drive signal PWMA and the second drive signal PWMB are the same, and are both determined by the comparison result between the second DC signal currently sampled and obtained by the control circuit 25 and the preset power supply threshold.

[0063] It is worth noting that the first level state in this article can specifically correspond to a low level or a 0 level, and the second level state corresponds to a high level; or the first level state can specifically correspond to a high level, and the second level state corresponds to a low level or a 0 level.

[0064] Furthermore, the first switch sub-circuit 211 is used to receive the first drive signal PWMA, and in response to the level change of the first drive signal PWMA, control the switching time point of its internal switch state, thereby triggering the first switch sub-circuit 211 to change the switch state.

[0065] The second switch subcircuit 212 is used to receive the second drive signal PWMB, and to control the switching time point of its internal switch state in response to the level change of the second drive signal PWMB, triggering the second switch subcircuit 212 to change the switch state to coordinate with the change of the switch state of the first switch subcircuit 211, to adjust the first AC signal, and to minimize switching losses, improve efficiency and reduce electromagnetic interference by triggering the switch state change when the voltage drops to the zero crossing point.

[0066] In one embodiment, the control circuit 25 further includes a sampling circuit 251, a signal processing circuit (not shown) and a driving circuit 252. The sampling circuit 251 is coupled to the isolation transformer 23 and the signal processing circuit, the signal processing circuit is coupled to the driving circuit 252, and the driving circuit 252 is coupled to the inverter circuit 21 and the rectifier circuit 24.

[0067] The sampling circuit 251 is used to sample and obtain the first AC signal and / or the second AC signal from the isolation transformer 23 .

[0068] The signal processing circuit is used to receive the first AC signal and / or the second AC signal, and to adjust its internal parameters in response to the rise and / or fall of the first AC signal voltage, and / or the rise and / or fall of the second AC signal voltage, so as to control the drive circuit 252 to change the level state of the first control signal, so as to use the first control signal to trigger the rectifier circuit 24 to change the switching state, thereby adjusting the second DC signal, and adjusting the current flowing through the resonant circuit 22 via the isolation transformer 23.

[0069] Furthermore, in one embodiment, the control circuit 25 specifically includes a first proportional filter correction circuit 2531 and a second proportional filter correction circuit 2532, and the sampling circuit 251 includes a first sampling circuit (not shown in the figure) and a second sampling circuit (not shown in the figure), the first sampling circuit is coupled to the isolation transformer 23 and the first proportional filter correction circuit 2531, and the second sampling circuit is coupled to the rectifier circuit 24 and the second proportional filter correction circuit 2532.

[0070] The first sampling circuit is used to sample the first AC signal and / or the second AC signal in the isolation transformer 23 . The second sampling circuit is used to sample and obtain the second DC signal in the rectifier circuit 24 .

[0071] The first proportional filter correction circuit 2531 receives the first AC signal and / or the second AC signal, and compares, filters, and corrects the first AC signal and / or the second AC signal with a reference value in turn, and then sends them to the signal processing circuit, so that the signal processing circuit controls the drive circuit 252 to generate a third drive signal PWM1 and a fourth drive signal PWM2 accordingly. Through the above signal processing steps, high-quality input is provided to the control circuit 25, thereby optimizing the overall performance and reliability, and effectively realizing efficient control.

[0072] In addition, the second proportional filter correction circuit 2532 is used to receive the second DC signal sent by the second sampling circuit, and compares the second DC signal with the reference value, filters, and corrects it in sequence, and then sends it to the signal processing circuit, so that the signal processing circuit controls the drive circuit 252 to generate the first drive signal PWMA and the second drive signal PWMB accordingly. Through the above-mentioned signal processing steps, high-quality input is provided to the control circuit 25, thereby optimizing the overall performance and reliability, and effectively realizing efficient control.

[0073] In one embodiment, the rectifier circuit 24 includes a third switch sub-circuit 241 and a fourth switch sub-circuit 242, and the isolation transformer 23 further includes a primary winding 231 and a secondary winding 232. The primary winding 231 is coupled to the resonant circuit 22, the first switch sub-circuit 211, and the second switch sub-circuit 212, and is coupled to the secondary winding 232. The secondary winding 232 is coupled to the third switch sub-circuit 241, the fourth switch sub-circuit 242 and the sampling circuit. The third switch sub-circuit 241 is coupled to the fourth switch sub-circuit 242 and the control circuit 25, and is used to couple to the load circuit 102. The fourth switch sub-circuit 242 is coupled to the control circuit 25.

[0074] Among them, the first control signal further includes a third drive signal PWM1 and a fourth drive signal PWM2, and the third drive signal PWM1 and the fourth drive signal PWM2 have opposite phases, that is, the level states of the two are opposite. When the third drive signal PWM1 is in the first level state, the fourth drive signal PWM2 is in the second level state; when the third drive signal PWM1 is in the second level state, the fourth drive signal PWM2 is in the first level state.

[0075] The first AC signal includes a first voltage signal at both ends of the primary winding 231 , and the second AC signal includes a second voltage signal at both ends of the secondary winding 232 .

[0076] Furthermore, the primary winding 231 is used to receive the regulated first AC signal sent by the resonant circuit 22, and convert the first AC signal into a second AC signal through electromagnetic coupling with the secondary winding 232, so as to use electromagnetic connection instead of electrical connection, so as to achieve primary and secondary electrical isolation and voltage matching, and meet the primary and secondary electrical safety insulation requirements.

[0077] The secondary winding 232 further sends the second AC signal to the third switch sub-circuit 241 and the fourth switch sub-circuit 242, so that the third switch sub-circuit 241 and the fourth switch sub-circuit 242 respond to the level change of the first control signal and control the switching time point of their internal switch states to convert the second AC signal into a second DC signal.

[0078] Specifically, the third switch subcircuit 241 is used to receive the third drive signal PWM1, so as to control the switching time point of its internal switch state in response to the level change of the third drive signal PWM1. Specifically, the third drive signal PWM1 changes its level state when the first voltage signal rises and falls, and / or the second voltage signal rises and falls, so as to trigger the third switch subcircuit 241 to change the switch state.

[0079] The fourth switch subcircuit 242 is used to receive the fourth drive signal PWM2, so as to control the switching time point of its internal switch state in response to the level change of the fourth drive signal PWM2. Specifically, the fourth drive signal PWM2 changes the level state when the first voltage signal rises and falls, and / or the second voltage signal rises and falls, so as to trigger the fourth switch subcircuit 242 to change the switch state, so as to coordinate with the change of the switch state of the third switch subcircuit 241, adjust the second DC signal, and in turn adjust the current flowing through the resonant circuit 22 through the isolation transformer 23. For example, before the switch state of the first switch subcircuit 211 and the second switch subcircuit 212 is triggered to change, the current flowing through the resonant circuit 12 is maintained without changing phase, so as to ensure the realization of ZVS opening and closing of the inverter circuit, so as to minimize switching loss, improve efficiency and reduce electromagnetic interference.

[0080] Furthermore, in one embodiment, the control circuit 25 adjusts the third drive signal PWM1 from the first level state to the second level state when it is determined that the first voltage signal or the second voltage signal rises, that is, detects that a rising edge appears in the waveform of the first voltage signal or the second voltage signal, or the voltage change rate of the first voltage signal is greater than the first set rate, or the voltage change rate of the second voltage signal is greater than the first set rate, and adjusts the third drive signal PWM1 from the second level state to the first level state when the first voltage signal or the second voltage signal drops.

[0081] Similarly, the control circuit 25 will also adjust the fourth drive signal PWM2 from the first level state to the second level state in response to the first voltage signal or the second voltage signal falling, and adjust the fourth drive signal PWM2 from the second level state to the first level state when the first voltage signal and / or the second voltage signal rises, that is, when a rising edge is detected in the waveform of the first voltage signal or the second voltage signal, or the voltage change rate of the first voltage signal is greater than the second set rate, or the voltage change rate of the second voltage signal is greater than the second set rate.

[0082] In other embodiments, the second AC signal specifically also includes a first current signal Iup flowing through the third switch sub-circuit 241 and a second current signal Idn flowing through the fourth switch sub-circuit 242, and the control circuit 25 can specifically adjust the third drive signal PWM1 from the second level state to the first level state when it is determined that the first current signal Idn decays forward to 0; and adjust the fourth drive signal PWM2 from the second level state to the first level state when it is determined that the second current signal Idn decays forward to 0.

[0083] It is worth noting that if Figure 2 As shown, the first current signal Iup may specifically correspond to the current flowing between the node N1 and the node N2, and the second current signal Idn may specifically correspond to the current flowing between the node N3 and the node N2.

[0084] In another embodiment, the secondary winding 232 may further include a first sub-secondary winding 2321 and a second sub-secondary winding 2322. The control circuit 25 may further include a sampling circuit 251, a signal processing circuit (not shown) and a driving circuit 252. The sampling circuit 251 also includes a third sampling circuit 2511 and a fourth sampling circuit 2512. The first sub-secondary winding 2321 is coupled to the third switch sub-circuit 241, the second sub-secondary winding 2322 is coupled to the fourth switch sub-circuit 242, and both are coupled to the primary winding 231. The third sampling circuit 2511 is coupled to the third switch sub-circuit 241 and the signal processing circuit, the fourth sampling circuit 2512 is coupled to the fourth switch sub-circuit 242 and the signal processing circuit, the signal processing circuit is coupled to the driving circuit 252, and the driving circuit 252 is coupled to the first switch sub-circuit 211, the second switch sub-circuit 212, the third switch sub-circuit 241 and the fourth switch sub-circuit 242.

[0085] The second voltage signal further includes a first secondary voltage signal Vup and a second secondary voltage signal Vdn.

[0086] It is worth noting that if Figure 2As shown, the first secondary voltage signal Vup may specifically correspond to the voltage between the node N1 and the node N4, and the second secondary voltage signal Vdn may specifically correspond to the voltage between the node N3 and the node N4.

[0087] Among them, the third sampling circuit 2511 is used to sample and obtain the first secondary voltage signal Vup, and the fourth sampling circuit 2512 is used to sample and obtain the second secondary voltage signal Vdn. The signal processing circuit can also specifically respond to the rise of the currently acquired first secondary voltage signal Vup, that is, when a rising edge is detected in the waveform of the first secondary voltage signal Vup, or the voltage amplitude change rate of the first secondary voltage signal Vup is greater than the first set rate, the control drive circuit 252 adjusts the third drive signal PWM1 from the first level state to the second level state, and responds to the currently acquired first current signal Iup decaying from the positive direction to 0, the control drive circuit 252 adjusts the third drive signal PWM1 from the second level state to the first level state.

[0088] Similarly, the signal processing circuit will also respond to the rise of the second secondary voltage signal Vdn, that is, when a rising edge is detected in the waveform of the second secondary voltage signal Vdn, or the voltage amplitude change rate of the second secondary voltage signal Vdn is greater than the second set rate, the control drive circuit 252 will adjust the fourth drive signal PWM2 from the first level state to the second level state, and in response to the currently acquired second current Idn decaying positively to 0, the control drive circuit 252 will adjust the fourth drive signal PWM2 from the second level state to the first level state.

[0089] Among them, when the level state of the third drive signal PWM1 changes, it will trigger the third switch sub-circuit 241 to change the switch state; when the level state of the fourth drive signal PWM2 changes, it will trigger the fourth switch sub-circuit 242 to change the switch state, so as to coordinate with the change of the switch state of the third switch sub-circuit 241, adjust the second DC signal, and in turn adjust the current flowing through the resonant circuit 22 through the isolation transformer 23. For example, before the switch state of the first switch sub-circuit 211 and the second switch sub-circuit 212 is triggered to change, the current flowing through the resonant circuit 12 is maintained without changing phase to ensure the realization of ZVS opening and closing of the inverter circuit, so as to minimize switching losses, improve efficiency and reduce electromagnetic interference.

[0090] In one embodiment, when the control circuit 25 determines that the signal frequency of the current second control signal is less than the resonant frequency of the resonant circuit, the first drive signal PWMA is in the second level state, the second drive signal PWMB is in the first level state, the third drive signal PWM1 is in the first level state, and the fourth drive signal PWM2 is in the second level state stage, and / or, when the first drive signal PWMA is in the first level state, the second drive signal PWMB is in the second level state, the third drive signal PWM1 is in the second level state, and the fourth drive signal PWM2 is in the first level state stage, the third current I flowing through the resonant circuit 22 L The third current I L Before the switch states of the first switch sub-circuit 211 and the second switch sub-circuit 212 are triggered to change, the third current I flowing through the resonant circuit 12 is maintained. L The phase is not changed to ensure that the inverter circuit 21 can achieve ZVS opening and closing, so that the power supply circuit 20 can not only achieve soft switching when working in a working range greater than or equal to the resonant frequency of the resonant circuit 22, but also can achieve soft switching in a working range lower than the resonant frequency, which effectively ensures the high efficiency and high reliability of the power supply circuit 20 in the full frequency working range, and also broadens the maximum gain range of the power supply circuit 20, facilitating a wider application.

[0091] In one embodiment, the first switch sub-circuit 211 specifically also includes a first switch tube T1 and a fourth switch tube T4, and the second switch sub-circuit 212 includes a second switch tube T2 and a third switch tube T3; wherein, the first end of the first switch tube T1 is coupled to the first end of the third switch tube T3, and is used to couple with the first end of the DC power supply 101, the second end of the first switch tube T1 is coupled to the first end of the second switch tube T2 and the first end of the resonant circuit 22, the second end of the third switch tube T3 is coupled to the first end of the fourth switch tube T4 and the second end of the isolation transformer 23, and the second end of the second switch tube T2 is coupled to the second end of the fourth switch tube T4, and is used to couple with the second end of the DC power supply 101.

[0092] It can be understood that the third end of each of the first switch tube T1, the second switch tube T2, the third switch tube T3 and the fourth switch tube T4 is coupled to the control output end of the control circuit 25, and correspondingly forms a full-bridge inverter circuit 21, which is used to receive the first drive signal PWMA and the second drive signal PWMB correspondingly sent by the control circuit 25, so as to trigger conduction or shutdown under the action of the first drive signal PWMA and the second drive signal PWMB, thereby converting the first DC signal into a first AC signal.

[0093] Optionally, the control circuit 25 can specifically adopt a PWM (Pulse Width Modulation) control strategy to implement on-off control of the full-bridge inverter circuit 21 composed of the first switch tube T1, the second switch tube T2, the third switch tube T3 and the fourth switch tube T4, so as to convert the first DC signal into a first AC signal to meet the power supply requirements of the load circuit 102 under different working conditions.

[0094] Optionally, the first switch tube T1, the second switch tube T2, the third switch tube T3, the fourth switch tube T4, and each "switch tube" below can specifically be one or more combinations of any reasonable switching devices such as MOS tubes, high-frequency transistors, triodes, thyristors, IGBTs, etc., and the present application does not limit this.

[0095] And the third end of each switch tube in this article corresponds to the control end, so that when the third end of each switch tube receives a corresponding driving signal, it will trigger the first end and the second end to be turned on under the second level state of the driving signal, and trigger the first end and the second end to be turned off under the first level state of the driving signal.

[0096] Furthermore, in one embodiment, the secondary winding 232 specifically also includes a first sub-secondary winding 2321 and a second sub-secondary winding 2322, and the third switch sub-circuit 241 includes a fifth switch tube T5, and the fourth switch sub-circuit 242 includes a sixth switch tube T6; wherein, the first end of the first sub-secondary winding 2321 is coupled to the first end of the fifth switch tube T5, the second end of the first sub-secondary winding 2321 is coupled to the second end of the second sub-secondary winding 2322, and is used to couple to the second end of the load circuit 102, the first end of the second sub-secondary winding 2322 is coupled to the first end of the sixth switch tube T6, the second end of the fifth switch tube T5 is coupled to the second end of the sixth switch tube T6, and is used to couple to the first end of the load circuit 102.

[0097] It can be understood that the third end of the fifth switch tube T5 and the third end of the sixth switch tube T6 are coupled to the control output end of the control circuit 25, and form a half-bridge rectifier circuit accordingly, so as to receive the third drive signal PWM1 and the fourth drive signal PWM2 sent by the control circuit 25 accordingly, so as to trigger conduction or shutdown under the action of the third drive signal PWM1 and the fourth drive signal PWM2, thereby converting the second AC signal into a second DC signal.

[0098] In one embodiment, the resonant circuit 22 further includes a resonant capacitor Cr and a resonant inductor Lr, wherein the first end of the resonant capacitor Cr is coupled to the second end of the first switch tube T1 and the first end of the second switch tube T2, the second end of the resonant capacitor Cr is coupled to the first end of the resonant inductor Lr, and the second end of the resonant inductor Lr is coupled to the first end of the primary winding 231.

[0099] It is worth noting that the resonant capacitor Cr and the resonant inductor Lr form a series resonance and have a specific resonant frequency.

[0100] Furthermore, in one embodiment, when the control circuit 25 determines that the signal frequency of the current second control signal is greater than or equal to the resonant frequency of the resonant circuit 22, it can also directly send the second control signal synchronously with the first control signal and make the second control signal the same as the first control signal.

[0101] When the control circuit 25 determines that the signal frequency of the current second control signal is less than or equal to the resonant frequency of the resonant circuit 22, the first AC signal and / or the second AC signal in the isolation transformer 23 are sampled to change the level state of the second control signal when the voltage of the first AC signal rises and / or falls, and / or the voltage of the second AC signal rises and / or falls, so as to trigger the rectifier circuit 24 to change the switching state, thereby adjusting the second DC signal and in turn adjusting the current flowing through the resonant circuit 22 through the isolation transformer 23, so as to ensure that the inverter circuit 21 achieves ZVS opening and closing, so as to minimize switching losses, improve efficiency and reduce electromagnetic interference.

[0102] In one embodiment, the power supply circuit 20 specifically further includes a filter output circuit 26, and the filter output circuit 26 further includes an output resistor Ro and an output capacitor Co, and the load circuit 102 can be specifically equivalent to a load resistor R, the first end of the output resistor Ro is coupled to the second end of the fifth switch tube T5, the second end of the sixth switch tube T6 and the first end of the load resistor R, the second end of the output resistor Ro is coupled to the first end of the output capacitor Co, and the second end of the output capacitor Co is coupled to the second end of the first sub-secondary winding 2321, the second end of the second sub-secondary winding 2322 and the second end of the load resistor R. The output resistor Ro is used to cooperate with the output capacitor Co to stably output the second DC signal to the load resistor R.

[0103] In other embodiments, the load circuit 102 can also be equivalent to a load capacitor (not shown) or a load inductor (not shown), or a combination of any two or three of the output resistance Ro, the load capacitor and the load inductor, or any other reasonable circuit architecture with different circuit elements and connection methods, which is not limited in the present application.

[0104] To facilitate the description of the specific control strategy of the control circuit 25, please continue to refer to Figure 3a-3d ,in, Figure 3a yes Figure 2 The equivalent circuit diagram of the resonant circuit in working mode 1 is as follows: Figure 3b yes Figure 2The equivalent circuit diagram of the resonant circuit in working mode 2 is as follows: Figure 3c yes Figure 2 The equivalent circuit diagram of the resonant circuit in working mode 3 is as follows: Figure 3d yes Figure 2 Equivalent circuit diagram of the resonant circuit in operating mode 4.

[0105] It is understandable that the first drive signal PWMA, the second drive signal PWMB, the third drive signal PWM1 and the fourth drive signal PWM2 all have a first level state and a second level state, and when any one or more drive signals are in the second level state, each switch tube receiving the drive signal will be triggered to turn on, and when any one or more drive signals are in the first level state, each switch tube receiving the drive signal will be triggered to turn off. The different on-off states of the switches on the primary and secondary sides of the isolation transformer 23 will correspond to four different working modes of the resonant circuit 22.

[0106] In addition, the voltage of the first DC signal provided by the DC power supply is Vdc; the voltage of the second DC signal output by the power supply circuit to the load circuit is Vo, and the current is Io; the current flowing through the resonant circuit 22 is I L .

[0107] Mode 1 (mode1): The first drive signal PWMA is at the second level, the second drive signal PWMB is at the first level, the first switch tube T1 is turned on, the second switch tube T2 is turned off, the third switch tube T3 is turned off, and the fourth switch tube T4 is turned on; the third drive signal PWM1 is at the second level, the fourth drive signal PWM2 is at the first level, the fifth switch tube T5 is turned on, and the sixth switch tube T6 is turned off. Figure 3a At this time, the input side voltage of the resonant circuit 22 is Vdc, and the output side voltage of the resonant circuit 22 is the positive voltage Vo*N (N is a positive number and is the transformation ratio coefficient of the isolation transformer 23) converted from the secondary side to the primary side by the output voltage Vo of the second DC signal through the isolation transformer 23.

[0108] Mode 2 (mode2): The first drive signal PWMA is at the first level, the second drive signal PWMB is at the second level, the first switch tube T1 is turned off, the second switch tube T2 is turned on, the third switch tube T3 is turned on, and the fourth switch tube T4 is turned off; the third drive signal PWM1 is at the first level, the fourth drive signal PWM2 is at the second level, the fifth switch tube T5 is turned off, and the sixth switch tube T6 is turned on. Figure 3b At this time, the voltage on the input side of the resonant circuit 22 is -Vdc, and the voltage on the output side of the resonant circuit 22 is a negative voltage -Vo*N.

[0109] Mode 3: The first drive signal PWMA is at the first level, the second drive signal PWMB is at the second level, the first switch tube T1 is turned off, the second switch tube T2 is turned on, the third switch tube T3 is turned on, and the fourth switch tube T4 is turned off; the third drive signal PWM1 is at the second level, the fourth drive signal PWM2 is at the first level, the fifth switch tube T5 is turned on, and the sixth switch tube T6 is turned off. Figure 3c At this time, the input side voltage of the resonant circuit 22 is -Vdc, and the output side voltage of the resonant circuit 22 is a positive voltage Vo*N.

[0110] Mode 4: The first drive signal PWMA is at the second level, the second drive signal PWMB is at the first level, the first switch tube T1 is turned on, the second switch tube T2 is turned off, the third switch tube T3 is turned off, and the fourth switch tube T4 is turned on; the third drive signal PWM1 is at the first level, the fourth drive signal PWM2 is at the second level, the fifth switch tube T5 is turned off, and the sixth switch tube T6 is turned on. Figure 3d At this time, the input side voltage of the resonant circuit 22 is Vdc, and the output side voltage of the resonant circuit 22 is a negative voltage -Vo*N.

[0111] The control circuit 25 specifically samples and obtains the output voltage Vo and the output current Io of the second DC signal output to the load circuit 102, so as to determine the signal frequency f of the first drive signal PWMA and the second drive signal PWMB after feedback loop compensation operation. Assuming that the resonant frequency of the resonant circuit 22 is fs, the power supply circuit 20 will have the following three typical working states under different input and output scenarios.

[0112] Please continue reading Figure 4a-4c ,in, Figure 4a yes Figure 2 Schematic diagram of waveforms of each sampling signal and control signal when the signal frequency of the second control signal given by the control circuit is greater than the resonant frequency of the resonant circuit, Figure 4b yes Figure 2 Schematic diagram of waveforms of various sampling signals and control signals when the signal frequency of the second control signal given by the control circuit is equal to the resonant frequency of the resonant circuit, Figure 4c yes Figure 2 Schematic diagram of waveforms of each sampling signal and control signal when the signal frequency of the second control signal given by the control circuit is lower than the resonant frequency of the resonant circuit.

[0113] Working state 1 (f>fs):

[0114] like Figure 4aAs shown, the signal frequency f of the first drive signal PWMA and the second drive signal PWMB is greater than the resonant frequency fs of the resonant circuit 22. When the second drive signal PWMB is in the first level state and the first drive signal PWMA is in the second level state, the input side voltage of the resonant circuit 22 is Vdc; at the same time, due to the detection of the change of the third voltage Vup rising and the fourth voltage Vdn falling, or directly sending the third drive signal PWM1 synchronously with the first drive signal PWMA, the third drive signal PWM1 is the same as the first drive signal PWMA, and the fourth drive signal PWM2 is sent synchronously with the second drive signal PWMB, and the fourth drive signal PWM2 is the same as the second drive signal PWMB, then the third drive signal PWM1 will be adjusted from the first level state to the second level state, and the fourth drive signal PWM2 will be adjusted from the second level state to the first level state, and the output side voltage of the resonant circuit 22 is the positive voltage Vo*N converted from the secondary side to the primary side by the output voltage Vo of the second DC signal through the isolation transformer 23. At this time, the resonant circuit 22 works in mode1.

[0115] When the first drive signal PWMA is in the first level state and the second drive signal PWMB is in the second level state, the input side voltage of the resonant circuit 22 is -Vdc; at the same time, due to the detection of the change of the fourth voltage Vdn rising and the third voltage Vup falling, or directly sending the third drive signal PWM1 and the first drive signal PWMA synchronously, the third drive signal PWM1 is the same as the first drive signal PWMA, and the fourth drive signal PWM2 is sent synchronously with the second drive signal PWMB, and the fourth drive signal PWM2 is the same as the second drive signal PWMB, then the third drive signal PWM1 is in the second level state, the fourth drive signal PWM2 will be adjusted from the second level state to the first level state, and the output side voltage of the resonant circuit 22 is a negative voltage -Vo*N. At this time, the resonant circuit 22 works in mode2.

[0116] pass Figure 4a It can be seen from the waveforms of each signal that the resonant circuit 22 works alternately in mode 1 and mode 2, and the first switch tube T1, the second switch tube T2, the third switch tube T3 and the fourth switch tube T4 on the primary side of the isolation transformer 23 can achieve ZVS opening, and the fifth switch tube T5 and the sixth switch tube T6 on the secondary side of the isolation transformer 23 can achieve ZCS opening and small current shutdown.

[0117] Working state 2 (f=fs):

[0118] like Figure 4bAs shown, the signal frequency f of the first drive signal PWMA and the second drive signal PWMB is equal to the resonant frequency fs of the resonant circuit 22. When the second drive signal PWMB is in the first level state and the first drive signal PWMA is in the second level state, the input side voltage of the resonant circuit 22 is Vdc; at the same time, due to the detection of the rise of the fourth voltage Vdn and the decrease of the third voltage Vup, or directly sending the third drive signal PWM1 and the first drive signal PWMA synchronously, the third drive signal PWM1 is the same as the first drive signal PWMA, and the fourth drive signal PWM2 is sent synchronously with the second drive signal PWMB, and the fourth drive signal PWM2 is the same as the second drive signal PWMB, then the third drive signal PWM1 will be adjusted from the first level state to the second level state, and the fourth drive signal PWM2 will be adjusted from the second level state to the first level state, and the output side voltage of the resonant circuit 22 is the positive voltage Vo*N. At this time, the resonant circuit 22 works in mode1.

[0119] When the first drive signal PWMA is in the first level state and the second drive signal PWMB is in the second level state, the input side voltage of the resonant circuit 22 is -Vdc; at the same time, due to the detection of the change of the third voltage Vup rising and the fourth voltage Vdn falling, or directly sending the third drive signal PWM1 and the first drive signal PWMA synchronously, the third drive signal PWM1 is the same as the first drive signal PWMA, and the fourth drive signal PWM2 is sent synchronously with the second drive signal PWMB, and the fourth drive signal PWM2 is the same as the second drive signal PWMB, then the third drive signal PWM1 will be adjusted from the first level state to the second level state, and the fourth drive signal PWM2 will be adjusted from the second level state to the first level state, and the output side voltage of the resonant circuit 22 is a negative voltage -Vo*N. At this time, the resonant circuit 22 operates in mode2.

[0120] pass Figure 4b It can be seen from the waveforms of each signal that the resonant circuit 22 works alternately in mode 1 and mode 2, and the first switch tube T1, the second switch tube T2, the third switch tube T3 and the fourth switch tube T4 on the primary side of the isolation transformer 23 can achieve ZVS opening, and the fifth switch tube T5 and the sixth switch tube T6 on the secondary side of the isolation transformer 23 can achieve ZCS opening and ZCS closing.

[0121] Working state three (f <fs):

[0122] like Figure 4cAs shown, the signal frequency f of the first drive signal PWMA and the second drive signal PWMB is less than the resonant frequency fs of the resonant circuit 22. When the first drive signal PWMA is in the second level state, the input side voltage of the resonant circuit 22 is Vdc; at the same time, due to the detection of the change of the third voltage Vup rising and the fourth voltage Vdn falling, after the third drive signal PWM1 is adjusted from the first level state to the second level state, the current flowing through the fifth switch tube T5 does not decay toward 0 in the positive direction, the third drive signal PWM1 remains turned on, and the output side voltage of the resonant circuit 22 is a positive voltage Vo*N. At this time, the resonant circuit 22 works in mode1.

[0123] After about half of the resonant cycle of the resonant circuit 22, the first drive signal PWMA is maintained to be turned on, and the input side voltage of the resonant circuit 22 is Vdc; the resonant circuit 22 resonates to the excitation current of the isolation transformer 23, which will cause the current flowing through the fifth switch tube T5 to decay to 0 in the positive direction, and the third drive signal PWM1 will be adjusted from the second level state to the first level state. At the same time, the control circuit 25 detects the change of the fourth voltage Vdn rising and the third voltage Vup falling, and the fourth drive signal PWM2 will be adjusted from the first level state to the second level state, and the output side voltage of the resonant circuit 22 becomes a negative voltage -Vo*N. At this time, the resonant circuit 22 works in mode4.

[0124] When the first drive signal PWMA is in the first level state and the second drive signal PWMB is in the second level state, the input side voltage of the resonant circuit 22 is -Vdc; at the same time, due to the detection of the change of the fourth voltage Vdn rising and the third voltage Vup falling, the fourth drive signal PWM2 is adjusted from the first level state to the second level state, and the current flowing through the sixth switch tube T6 does not decay toward 0 in the positive direction, the fourth drive signal PWM2 maintains the second level state, and the output side voltage of the resonant circuit 22 is a negative voltage -Vo*N. At this time, the resonant circuit 22 works in mode2.

[0125] After about half of the resonant cycle of the resonant circuit 22, the second drive signal PWMB maintains the second level state, and the input side voltage of the resonant circuit 22 is -Vdc; the excitation current flowing through the resonant circuit 22 and resonating to the isolation transformer 23 will cause the current flowing through the sixth switch tube T6 to decay to 0 in the forward direction, and the fourth drive signal PWM2 will be adjusted from the second level state to the first level state; at the same time, the control circuit 25 detects the change of the third voltage Vup rising and the fourth voltage Vdn falling, and the third drive signal PWM1 will be adjusted from the first level state to the second level state, and the output side voltage of the resonant circuit 22 becomes the positive voltage Vo*N. At this time, the resonant circuit 22 works in mode3.

[0126] pass Figure 4cIt can be seen from the waveforms of each signal that the resonant circuit 22 works alternately in mode 1, mode 4, mode 2 and mode 3, and due to the existence of mode 3 and mode 4, the excitation current can be well maintained to the switching process of the first drive signal PWMA and the second drive signal PWMB, that is, the third current I flowing through the resonant circuit 22 L Before the switching states of the first switch tube T1, the second switch tube T2, the third switch tube T3 and the fourth switch tube T4 are triggered to change, the third current I flowing through the resonant circuit 12 is maintained. L The phase is not changed to ensure the realization of ZVS opening and closing of the inverter circuit, and to ensure that the first switch tube T1, the second switch tube T2, the third switch tube T3 and the fourth switch tube T4 on the primary side of the isolation transformer 23 can achieve ZVS opening, and at the same time, the fifth switch tube T5 and the sixth switch tube T6 on the secondary side of the isolation transformer 23 can achieve ZCS opening.

[0127] It can be seen that through the analysis of the above typical working conditions, by adopting the power supply circuit 20 and the corresponding control method of this embodiment, the signal frequency of the control signal used by the power supply circuit 20 can not only realize soft switching when working in a working range greater than or equal to the resonant frequency of the resonant circuit 22, but also can realize soft switching in a working range lower than the resonant frequency of the resonant circuit 22, which can well realize high efficiency, high reliability and low noise operation.

[0128] In addition, in the mode 3 and mode 4 stages, the voltage across the resonant circuit 22 will be greater than the voltage Vdc of the first DC signal provided by the DC power supply 101, and specifically can be twice the first DC signal voltage Vdc, or any reasonable set voltage interval greater than the first DC signal voltage Vdc with twice the first DC signal voltage Vdc as the intermediate value, thereby enabling the resonant circuit 22 to store more electrical energy corresponding to the current control stage, so that when the power supply circuit 20 is powered off, the more electrical energy stored in the resonant circuit 22 can effectively extend the power-off retention time of the resonant circuit 22.

[0129] Please continue reading Figure 5 , Figure 5 yes Figure 2 A schematic structural diagram of another embodiment of an inverter circuit in a power supply circuit.

[0130] In another embodiment, the first switch sub-circuit 211 may further specifically include a seventh switch tube T7, and the second switch sub-circuit 212 includes an eighth switch tube T8; wherein the first end of the seventh switch tube T7 is used to couple with the first end of the DC power supply 101, the second end of the seventh switch tube T7 is coupled with the first end of the eighth switch tube T8 and the first end of the resonant circuit 22, the second end of the eighth switch tube T8 is coupled with the second end of the isolation transformer 23, and is used to couple with the second end of the DC power supply 101, and the third end of the seventh switch tube T7 and the third end of the eighth switch tube T8 are coupled to the control output end of the control circuit 25.

[0131] It is understandable that the seventh switch tube T7 and the eighth switch tube T8 can also specifically form a half-bridge inverter circuit 21, which is used to receive the first drive signal PWMA and the second drive signal PWMB sent by the control circuit 25, and trigger conduction or shutdown under the action of the first drive signal PWMA and the second drive signal PWMB, thereby converting the first DC signal into a first AC signal.

[0132] In other embodiments, the inverter circuit 21 may be any reasonable circuit form for realizing inversion, such as a symmetrical half-bridge or an asymmetrical half-bridge, and the present application does not limit this.

[0133] Please continue reading Figure 6 , Figure 6 yes Figure 2 A structural schematic diagram of another embodiment of a rectifier circuit in a power supply circuit.

[0134] In another embodiment, the third switch sub-circuit 241 may further include a ninth switch tube T9 and a twelfth switch tube T12, and the fourth switch sub-circuit 242 includes a tenth switch tube T10 and an eleventh switch tube T11; wherein, the first end of the secondary winding 232 is coupled to the first end of the ninth switch tube T9 and the second end of the tenth switch tube T10, the second end of the secondary winding 232 is coupled to the first end of the eleventh switch tube T11 and the second end of the twelfth switch tube T12, the second end of the ninth switch tube T9 is coupled to the second end of the eleventh switch tube T11, and is used to couple to the first end of the load circuit 102, the first end of the tenth switch tube T10 is coupled to the first end of the twelfth switch tube T12, and is used to couple to the second end of the load circuit 102, and the third end of each of the ninth switch tube T9, the tenth switch tube T10, the eleventh switch tube T11 and the twelfth switch tube T12 is coupled to the control output end of the control circuit 25.

[0135] It can be understood that the ninth switch tube T9, the twelfth switch tube T12, the tenth switch tube T10 and the eleventh switch tube T11 can also form a full-bridge rectifier circuit to receive the third drive signal PWM1 and the fourth drive signal PWM2 sent by the control circuit 25, and trigger conduction or shutdown under the action of the third drive signal PWM1 and the fourth drive signal PWM2, thereby converting the second AC signal into a second DC signal.

[0136] In other embodiments, the rectifier circuit 24 may be any reasonable circuit form for achieving rectification, such as forward full-wave rectification or reverse full-wave rectification, and the present application does not limit this.

[0137] This application also specifically adopts a power control method, see Figure 7 , Figure 7 This is a flow chart of an implementation method of the power control method of the present application. Specifically, it may include the following steps:

[0138] S31: Receive a first DC signal sent by an external DC power source.

[0139] It is understandable that the power control method in this embodiment is specifically a control method in which the power circuit uses the DC power provided by the external DC power supply to convert the DC power into AC power and then convert it back into DC power. The power circuit specifically includes an inverter circuit, a resonant circuit, an isolation transformer, a rectifier circuit and a control circuit, the inverter circuit is used to couple with the DC power supply, the resonant circuit is coupled with the inverter circuit, the isolation transformer is coupled with the resonant circuit, the rectifier circuit is coupled with the isolation transformer and is used to couple with the load circuit, and the control circuit is coupled with the inverter circuit and the rectifier circuit.

[0140] Specifically, the inverter circuit is used to receive a first DC signal with a constant current and / or voltage provided by an external DC power source.

[0141] S32: Convert the first DC signal into a first AC signal.

[0142] Furthermore, the inverter circuit utilizes its internal switching action mechanism, such as the opening and closing action mechanism of switching devices such as IGBT, high-frequency transistor, MOS, etc., to quickly switch the DC power under signal control to generate an alternating voltage waveform and obtain a first AC signal.

[0143] S33: Adjust the first AC signal.

[0144] The resonant circuit receives the first AC signal sent by the inverter circuit, and performs one or more of any reasonable signal adjustments such as filtering, shaping, phase shifting, etc. on the first AC signal, in order to achieve better output characteristics and ensure that subsequent links, such as rectifier circuits or loads, obtain more stable and efficient electrical energy.

[0145] S34: Convert the adjusted first AC signal into a second AC signal.

[0146] The isolation transformer receives the regulated first AC signal sent by the resonant circuit, and converts the regulated first AC signal into a second AC signal, so as to replace the electrical connection with an electromagnetic connection, so as to realize the safety electrical isolation and voltage matching between the primary and secondary sides, and meet the safety insulation requirements for the primary and secondary sides.

[0147] S35: Convert the second AC signal into a second DC signal to output to an external load circuit.

[0148] The rectifier circuit receives the second AC signal sent by the isolation transformer, and further utilizes high-frequency rectification technology, such as PWM, synchronous rectification, reverse damping rectification, or any other reasonable rectification method, to obtain a stable DC output, i.e., a second DC signal, using the second AC signal to output to the load circuit to meet the power usage of the load circuit.

[0149] S36: Generate a first control signal based on the adjusted increase and / or decrease of the first AC signal voltage and / or the increase and / or decrease of the second AC signal voltage.

[0150] The control circuit is used to sample the first AC signal and / or the second AC signal from the voltage to generate a first control signal based on the rise and / or fall of the regulated first AC signal voltage and / or the rise and / or fall of the second AC signal voltage.

[0151] S37: Regulate the second DC signal using the first control signal.

[0152] The rectifier circuit is also used to receive a first control signal sent by the control circuit, so as to change the switch state under the action of the first control signal to adjust the second DC signal, and in turn adjust the current flowing through the resonant circuit through the isolation transformer. For example, before the switch state of the inverter circuit is triggered to change, the current flowing through the resonant circuit is maintained without changing phase to ensure the realization of ZVS opening and closing of the inverter circuit.

[0153] Furthermore, in one embodiment, after the above S35, the method further includes: comparing the second DC signal with a preset power supply threshold to determine the signal frequency of the second control signal; and regulating the first AC signal using the second control signal.

[0154] Specifically, the control circuit is also used to sample and obtain a second DC signal output to the load circuit from the rectifier circuit, to compare the currently obtained second DC signal with a preset power supply threshold, and to determine the signal frequency of the second control signal based on the comparison difference between the second DC signal and the preset power supply threshold, and then to send the second control signal to the inverter circuit according to the currently determined signal frequency, triggering the inverter circuit to adjust its switching state, so as to adjust the first AC signal corresponding to the output of the inverter circuit, and then adjust the second DC signal.

[0155] It is worth noting that the second DC signal includes a current signal and a voltage signal, and the preset power supply threshold can be specifically understood as the target power supply demand of the load circuit, such as the target setting value of the voltage, current or power of the power supply output currently required by the load circuit, and can also be understood as a preset target power supply signal. The control circuit specifically uses the difference between the second DC signal and the preset power supply threshold to dynamically adjust the signal frequency of the second control signal. For example, when it is determined that the second DC signal is less than the preset power supply threshold, the current signal frequency of the second control signal is increased, and when it is determined that the second DC signal is greater than the preset power supply threshold, the current signal frequency of the second control signal is decreased until the second DC signal is adjusted to the target setting value of the voltage, current or power, that is, within the range of the preset power supply threshold, and the signal frequency of the second control signal currently in a stable state is determined.

[0156] See also Figure 8 , Figure 8 yes Figure 7 Flow chart of an embodiment of step S36 in the embodiment. In one embodiment, the power control method of the present application includes some more specific steps in addition to the above steps S31-S37. Specifically, the above step S36 may also include the following steps:

[0157] S361: When the first voltage signal and / or the second voltage signal rises, adjust the third driving signal from the first level state to the second level state.

[0158] It can be understood that the inverter circuit specifically also includes a first switch subcircuit and a second switch subcircuit, the rectifier circuit includes a third switch subcircuit and a fourth switch subcircuit, the isolation transformer includes a primary winding and a secondary winding, the first switch subcircuit is coupled to the second switch subcircuit, the resonant circuit and the control circuit, and is used to couple with a DC power supply, the second switch subcircuit is coupled to the control circuit, the primary winding is coupled to the resonant circuit, the first switch subcircuit, the second switch subcircuit, and is coupled with the secondary winding, the secondary winding is coupled to the third switch subcircuit and the fourth switch subcircuit, the third switch subcircuit is coupled to the fourth switch subcircuit and the control circuit, and is used to couple with the load circuit, and the fourth switch subcircuit is coupled to the control circuit.

[0159] Among them, the first control signal includes a third drive signal and a fourth drive signal, and the third drive signal and the fourth drive signal have opposite phases, that is, the level states of the two are opposite. When the third drive signal is in the first level state, the fourth drive signal is in the second level state; when the third drive signal is in the second level state, the fourth drive signal is in the first level state.

[0160] The second control signal includes a first drive signal and a second drive signal, and the first drive signal and the second drive signal have opposite phases, that is, the level states of the two are opposite. When the first drive signal is in the first level state, the second drive signal is in the second level state; when the first drive signal is in the second level state, the second drive signal is in the first level state; and the signal frequencies of the first drive signal and the second drive signal are the same.

[0161] It is worth noting that the first level state may specifically correspond to a low level or a 0 level, and the second level state may correspond to a high level; or the first level state may specifically correspond to a high level, and the second level state may correspond to a low level or a 0 level. When the level state of the third driving signal changes, the third switch sub-circuit will be triggered to change the switch state.

[0162] The first AC signal specifically includes a first voltage signal across the primary winding, and the second AC signal includes a second voltage signal across the secondary winding, a first current signal flowing through the third switch subcircuit, and a second current signal flowing through the fourth switch subcircuit.

[0163] Specifically, when the control circuit determines that the currently acquired first voltage signal or second voltage signal rises, that is, detects that a rising edge appears in the waveform of the first voltage signal or the second voltage signal, or the voltage change rate of the first voltage signal is greater than the first set rate, or the voltage change rate of the second voltage signal is greater than the first set rate, the control circuit adjusts the third drive signal PWM1 from the first level state to the second level state.

[0164] S362: When the first voltage signal and / or the second voltage signal decreases, or the first current signal decays positively to 0, the third driving signal is adjusted from the second level state to the first level state.

[0165] Furthermore, when the control circuit detects that the currently acquired first voltage signal or second voltage signal decreases, or the first current signal decays in the positive direction to 0, the control circuit adjusts the third driving signal from the second level state to the first level state.

[0166] S363: When the first voltage signal and / or the second voltage signal decreases, adjust the fourth driving signal from the first level state to the second level state.

[0167] The control circuit will also adjust the fourth driving signal from the first level state to the second level state in response to the first voltage signal or the second voltage signal falling.

[0168] S364: When the first voltage signal and / or the second voltage signal rises, or the second current signal decays positively to 0, the fourth driving signal is adjusted from the second level state to the first level state.

[0169] The control circuit adjusts the fourth drive signal from the second level state to the first level state when it detects that the currently acquired first voltage signal and / or second voltage signal rises, that is, detects that a rising edge appears in the waveform of the first voltage signal or the second voltage signal, or the voltage change rate of the first voltage signal is greater than the second set rate, or the voltage change rate of the second voltage signal is greater than the second set rate; or, the control circuit can also specifically adjust the fourth drive signal from the second level state to the first level state when it is determined that the second current signal is forwardly decayed to 0.

[0170] Among them, when the level state of the third drive signal changes, it will trigger the third switch sub-circuit to change the switch state; when the level state of the fourth drive signal changes, it will trigger the fourth switch sub-circuit to change the switch state, so as to coordinate with the change of the switch state of the third switch sub-circuit, adjust the second DC signal, and trigger the switch state change when the current drops to the zero crossing point to minimize switching losses, improve efficiency and reduce electromagnetic interference.

[0171] It is understandable that in some other embodiments, the power supply circuit specifically includes some other more specific circuit units to be able to implement other more specific control methods. For details, please refer to Figure 1-Figure 6 And related text descriptions will not be repeated here.

[0172] This application also specifically adopts a power supply circuit, see Fig. 9 , Fig. 9 In this embodiment, the composite power circuit 30 includes a DC power supply 31 and at least two power supply circuits 32 , and the at least two power supply circuits 32 are connected in series or in parallel and coupled to the DC power supply 31 .

[0173] In one embodiment, the composite power supply circuit 30 specifically further includes at least two filter output circuits 33, and each filter output circuit 33 is coupled to a power supply circuit 32 to respectively constitute a first phase power supply circuit, a second phase power supply circuit, ..., an Mth phase power supply circuit (M is an integer greater than 1).

[0174] Among them, the composite power supply circuit 30 can be specifically understood as a hybrid circuit constructed by connecting multiple groups of inverter circuits 321 in series or in parallel, and multiple groups of transformer rectifier circuits 322 in series or in parallel, and then combining them in pairs. Multiple groups of the hybrid circuits are connected in series or in parallel to form a composite power supply circuit 30, and its control mode is the same as the above-mentioned power supply control method.

[0175] It should be noted that the power supply circuit 32 described in this embodiment is the power supply circuit 10 or the power supply circuit 20 described in any one of the above embodiments. Figure 1-Figure 6 And the related text content will not be repeated here.

[0176] This application also specifically uses an electronic device, see Fig.10 , Fig.10 Schematic diagram of the framework of an electronic device of the present application. In this embodiment, the electronic device 40 includes a housing 41 and a power circuit 42 or a composite power circuit (not shown) connected to the housing 41.

[0177] Optionally, the electronic device 40 may be any reasonable electronic mechanical device such as a server, a computer, an intelligent communication device, etc., and this application does not limit this.

[0178] It should be noted that the power circuit 42 described in this embodiment is the power circuit 10 or the power circuit 20 described in any one of the above embodiments. Figure 1-Figure 6 And the related text content will not be repeated here.

[0179] It should be noted that the composite power supply circuit described in this embodiment is the composite power supply circuit 30 described in any one of the above embodiments. Fig. 9 And the related text content will not be repeated here.

[0180] The beneficial effects of the present application are as follows: different from the prior art, the inverter circuit in the power supply circuit provided by the present application receives a first DC signal sent by a DC power supply, and converts the first DC signal into a first AC signal, so as to adjust the first AC signal by using a resonant circuit, the isolation transformer converts the adjusted first AC signal into a second AC signal, and the rectifier circuit converts the second AC signal into a second DC signal, so as to output it to the load circuit; wherein, the control circuit generates a first control signal based on the rise and / or fall of the voltage of the first AC signal or the second AC signal, and sends the first control signal to the rectifier circuit, so as to trigger the rectifier circuit to change the switch state under the action of the first control signal, so as to adjust the second DC signal, and adjust the current flowing through the resonant circuit through the isolation transformer, thereby effectively ensuring the realization of the ZVS (Zero Voltage Switch) of the inverter circuit, so as to ensure the high efficiency and high reliability of the power supply circuit in the full frequency working range, thereby effectively reducing the circuit loss and switching noise, widening the maximum gain range of the power supply circuit, and improving the overall efficiency and power density of the power supply circuit, so as to facilitate a wider range of applications.

[0181] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A power supply circuit, characterized in that: The power supply circuit comprises: an inverter circuit, configured to be coupled to a DC power supply to receive a first DC signal sent by the DC power supply and convert the first DC signal into a first AC signal; A resonant circuit coupled to the inverter circuit to receive and adjust a first AC signal sent by the inverter circuit; an isolation transformer, coupled to the resonant circuit to receive the regulated first AC signal sent by the resonant circuit and convert the regulated first AC signal into a second AC signal; a rectifier circuit, coupled to the isolation transformer and used to couple to a load circuit to receive the second AC signal sent by the isolation transformer and convert the second AC signal into a second DC signal to output to the load circuit; a control circuit coupled to the inverter circuit and the rectifier circuit, wherein the control circuit samples and obtains the second DC signal in the rectifier circuit, compares the second DC signal with a preset power supply threshold, determines a signal frequency of a second control signal, and sends the second control signal according to the signal frequency; The control circuit is further used to sample and obtain the first AC signal and / or the second AC signal in the isolation transformer, so as to generate a first control signal based on the rise and / or fall of the voltage of the first AC signal and / or the rise and / or fall of the voltage of the second AC signal; The inverter circuit is used to receive the second control signal and adjust the first AC signal based on the second control signal; The rectifier circuit is used to receive the first control signal and adjust the second DC signal based on the first control signal so as to maintain the current flowing through the resonant circuit unchanged when the rectifier circuit changes its switching state and before the switching state of the inverter circuit is triggered to change.

2. The power supply circuit according to claim 1, characterized in that: The inverter circuit includes a first switch subcircuit and a second switch subcircuit, the first switch subcircuit is coupled to the second switch subcircuit, the resonant circuit, the isolation transformer and the control circuit, and is used to couple to the DC power supply, the second switch subcircuit is coupled to the control circuit, and the second control signal includes a first drive signal and a second drive signal; Among them, the first switch sub-circuit is used to receive the first drive signal to change the switch state under the action of the first drive signal; the second switch sub-circuit is used to receive the second drive signal to change the switch state under the action of the second drive signal, and cooperate with the switch state of the first switch sub-circuit to adjust the first AC signal.

3. The power supply circuit according to claim 2, characterized in that: The control circuit includes a sampling circuit, a signal processing circuit and a driving circuit, wherein the sampling circuit is coupled to the isolation transformer and the signal processing circuit, the signal processing circuit is coupled to the driving circuit, and the driving circuit is coupled to the inverter circuit and the rectifier circuit; The sampling circuit samples and obtains the first AC signal and / or the second AC signal in the isolation transformer; The signal processing circuit is used to receive the first AC signal and / or the second AC signal, and in response to the rise and / or fall of the first AC signal voltage, and / or the rise and / or fall of the second AC signal voltage, control the drive circuit to change the level state of the first control signal, and send the first control signal to the rectifier circuit to trigger the rectifier circuit to change the switch state and regulate the second DC signal.

4. The power supply circuit according to claim 3, characterized in that: The control circuit further includes a first proportional filter correction circuit and a second proportional filter correction circuit, the sampling circuit includes a first sampling circuit and a second sampling circuit, the first sampling circuit is coupled to the isolation transformer and the first proportional filter correction circuit, and the second sampling circuit is coupled to the rectifier circuit and the second proportional filter correction circuit; Wherein, the first sampling circuit is used to sample and obtain the first AC signal and / or the second AC signal in the isolation transformer; The second sampling circuit is used to sample and obtain the second DC signal in the rectifier circuit; The first proportional filtering and correction circuit receives the first AC signal and / or the second AC signal, and compares the first AC signal and / or the second AC signal with a reference value, filters, and corrects the first AC signal and / or the second AC signal in sequence, and then sends the signals to the signal processing circuit, so that the signal processing circuit controls the drive circuit to generate the first control signal accordingly; The second proportional filter correction circuit receives the second DC signal, compares the second DC signal with a reference value, filters, and corrects the second DC signal in sequence, and then sends it to the signal processing circuit, so that the signal processing circuit controls the drive circuit to generate the first drive signal and the second drive signal accordingly.

5. The power supply circuit according to claim 2, characterized in that: The rectifier circuit includes a third switch subcircuit and a fourth switch subcircuit, the isolation transformer includes a primary winding and a secondary winding, the primary winding is coupled to the resonant circuit and coupled to the secondary winding, the secondary winding is coupled to the third switch subcircuit and the fourth switch subcircuit, the third switch subcircuit is coupled to the fourth switch subcircuit and the control circuit, and is used to couple to the load circuit, the fourth switch subcircuit is coupled to the control circuit, and the first control signal includes a third drive signal and a fourth drive signal; The primary winding is used to receive the adjusted first AC signal sent by the resonant circuit, and convert the first AC signal into the second AC signal through the secondary winding, so as to send it to the third switch sub-circuit and the fourth switch sub-circuit; the first AC signal includes a first voltage signal at both ends of the primary winding, and the second AC signal includes a second voltage signal at both ends of the secondary winding; The third switch sub-circuit is used to receive the third drive signal sent by the control circuit, and the third drive signal changes its level state when the first voltage signal rises and falls, and / or the second voltage signal rises and falls, so as to trigger the third switch sub-circuit to change its switch state; The fourth switch subcircuit is used to receive the fourth drive signal, and the fourth drive signal changes its level state when the first voltage signal rises and falls, and / or the second voltage signal rises and falls, so as to trigger the fourth switch subcircuit to change its switch state.

6. The power supply circuit according to claim 5, characterized in that: The second AC signal also includes a first current signal flowing through the third switch subcircuit and a second current signal flowing through the fourth switch subcircuit; The control circuit adjusts the third drive signal from the first level state to the second level state when determining that the first voltage signal and / or the second voltage signal rises, and adjusts the third drive signal from the second level state to the first level state when the first voltage signal and / or the second voltage signal drops, or the first current signal decays positively to 0; When the control circuit determines that the first voltage signal and / or the second voltage signal decreases, the control circuit adjusts the fourth drive signal from the first level state to the second level state, and when the first voltage signal and / or the second voltage signal rises, or the second current signal decays positively to 0, the control circuit adjusts the fourth drive signal from the second level state to the first level state.

7. The power supply circuit according to claim 6, characterized in that: The signal frequency is less than the resonant frequency of the resonant circuit, and the first drive signal is in the second level state, the second drive signal is in the first level state, the third drive signal is in the first level state, and the fourth drive signal is in the second level state stage; And / or, when the first drive signal is in the first level state, the second drive signal is in the second level state, the third drive signal is in the second level state, and the fourth drive signal is in the first level state, the third current flowing through the resonant circuit remains non-inverted.

8. The power supply circuit according to any one of claims 2 to 7, characterized in that: The first switch subcircuit includes a first switch tube and a fourth switch tube, and the second switch subcircuit includes a second switch tube and a third switch tube; wherein the first end of the first switch tube is coupled to the first end of the third switch tube and is used to couple with the first end of the DC power supply, the second end of the first switch tube is coupled to the first end of the second switch tube and the first end of the resonant circuit, the second end of the third switch tube is coupled to the first end of the fourth switch tube and the second end of the isolation transformer, the second end of the second switch tube is coupled to the second end of the fourth switch tube and is used to couple with the second end of the DC power supply, and the third end of each of the first switch tube, the second switch tube, the third switch tube and the fourth switch tube is coupled to the control output end of the control circuit; Or, the first switch sub-circuit includes a seventh switch tube, and the second switch sub-circuit includes an eighth switch tube; wherein, the first end of the seventh switch tube is used to couple with the first end of the DC power supply, the second end of the seventh switch tube is coupled with the first end of the eighth switch tube and the first end of the resonant circuit, the second end of the eighth switch tube is coupled with the second end of the isolation transformer and is used to couple with the second end of the DC power supply, and the third end of the seventh switch tube and the third end of the eighth switch tube are coupled to the control output end of the control circuit.

9. The power supply circuit according to any one of claims 5 to 7, characterized in that: The secondary winding includes a first sub-secondary winding and a second sub-secondary winding, the third switch sub-circuit includes a fifth switch tube, and the fourth switch sub-circuit includes a sixth switch tube; wherein the first end of the first sub-secondary winding is coupled to the first end of the fifth switch tube, the second end of the first sub-secondary winding is coupled to the second end of the second sub-secondary winding, and is used to couple with the second end of the load circuit, the first end of the second sub-secondary winding is coupled to the first end of the sixth switch tube, the second end of the fifth switch tube is coupled to the second end of the sixth switch tube, and is used to couple with the first end of the load circuit, and the third end of the fifth switch tube and the third end of the sixth switch tube are coupled to the control output end of the control circuit; Or, the third switch sub-circuit includes a ninth switch tube and a twelfth switch tube, and the fourth switch sub-circuit includes a tenth switch tube and an eleventh switch tube; wherein, the first end of the secondary winding is coupled to the first end of the ninth switch tube and the second end of the tenth switch tube, the second end of the secondary winding is coupled to the first end of the eleventh switch tube and the second end of the twelfth switch tube, the second end of the ninth switch tube is coupled to the second end of the eleventh switch tube, and is used to couple with the first end of the load circuit, the first end of the tenth switch tube is coupled to the first end of the twelfth switch tube, and is used to couple with the second end of the load circuit, and the third end of each of the ninth switch tube, the tenth switch tube, the eleventh switch tube and the twelfth switch tube is coupled to the control output end of the control circuit.

10. A power supply control method, used to control the power supply circuit according to any one of claims 1 to 9, characterized in that: The power control method comprises: receiving a first DC signal sent by an external DC power source; converting the first DC signal into a first AC signal; adjusting the first AC signal; converting the adjusted first AC signal into a second AC signal; converting the second AC signal into a second DC signal to output to an external load circuit; comparing the second DC signal with a preset power supply threshold to determine a signal frequency of a second control signal; adjusting the first AC signal based on the second control signal; generating a first control signal based on the adjusted increase and / or decrease of the first AC signal voltage and / or the increase and / or decrease of the second AC signal voltage; The second DC signal is adjusted using the first control signal so that when the first control signal changes its level state, and before the second control signal does not change its level state, the first AC signal is maintained unchanged.

11. The power control method according to claim 10, characterized in that: The first control signal includes a third drive signal and a fourth drive signal, the second AC signal includes a first voltage signal, a second voltage signal, a first current signal, and a second current signal, and the step of generating the first control signal based on the rise and / or fall of the regulated first AC signal voltage and / or the rise and / or fall of the second AC signal voltage includes: When the first voltage signal and / or the second voltage signal rises, adjusting the third driving signal from a first level state to a second level state; When the first voltage signal and / or the second voltage signal decreases, or the first current signal decays positively to 0, adjusting the third driving signal from the second level state to the first level state; When the first voltage signal and / or the second voltage signal decreases, adjusting the fourth driving signal from the first level state to the second level state; When the first voltage signal and / or the second voltage signal rises, or the second current signal decays positively to 0, the fourth driving signal is adjusted from the second level state to the first level state.

12. A composite power supply circuit, characterized in that: The composite power supply circuit comprises a DC power supply and at least two power supply circuits, wherein at least two of the power supply circuits are connected in series or in parallel with each other and are coupled to the DC power supply; Wherein, the power supply circuit is the power supply circuit as claimed in any one of claims 1-9.

13. An electronic device, characterized in that: The electronic device comprises a housing and a power circuit or a composite power circuit connected to the housing; Wherein, the power supply circuit is the power supply circuit as described in any one of claims 1 to 9; the composite power supply circuit is the composite power supply circuit as described in claim 12.

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