Control circuit, control method of switching power supply, and switching power supply

Abstract

The application discloses a control circuit and method of a switching power supply and the switching power supply. The switching power supply comprises N-phase power conversion circuits, N is an integer greater than or equal to 1, and the control circuit comprises: a current reference signal generation module configured to perform error integration on a first compensation signal and a first voltage signal to obtain an integrated signal, and superimpose the integrated signal and the first compensation signal to obtain a current reference signal; and a control module configured to obtain a control signal corresponding to each phase power conversion circuit according to the current reference signal, so as to control each phase power conversion circuit to provide a power output to a load. The first compensation signal represents difference information between an output feedback signal of the switching power supply and a preset reference voltage, and the first voltage signal represents average current information of each phase power conversion circuit in the N-phase power conversion circuit. The application can realize fast current limiting protection of the switching power supply, and can also improve the output precision of the output current of the switching power supply.

Description

Technical Field

[0001] This invention relates to the field of power converter technology, specifically to a control circuit, control method, and switching power supply for a switching power supply. Background Technology

[0002] Modern electronic components, such as central processing units (CPUs) and memory, are experiencing progressively lower driving voltages, which reduces their tolerance for voltage ripple. However, the power consumption of these components has not decreased at the same rate, resulting in an increase in the current required for operation. This higher current, in turn, leads to greater voltage ripple. To address this issue, multiphase converter architectures have been developed, distributing the current across multiple converter circuits. Compared to single-phase converter architectures, multiphase converter architectures not only excel in eliminating voltage ripple but also offer superior advantages in dynamic response, output ripple current elimination, and heat dissipation.

[0003] Traditional high dynamic response switching converters primarily employ a multi-channel interleaved parallel structure with dual-loop control (current and voltage loops) to improve dynamic response speed, maintain voltage control accuracy, and reduce voltage and current ripple. Voltage-mode control is the most commonly used control method in voltage-mode output power converters, capable of eliminating steady-state error and maintaining high accuracy. However, it cannot react immediately to load disturbances, resulting in less than ideal dynamic response speed. Current-mode control can be divided into average current control, peak current control, and valley current control, with peak current control being the most widely used. Peak current control is a control method that uses a fixed clock for onset and peak current for offset. This method improves the converter's response speed to input voltage and load current changes, while also facilitating overcurrent protection.

[0004] Existing switching power supplies achieve fast overcurrent protection by limiting the peak or valley value of the inductor current. However, since the inductance values ​​of each phase of a switching power supply have a relatively large distribution, it is difficult to make the current accuracy of the switching power supply high. At the same time, the fast current limiting effect of existing switching power supplies is relatively poor.

[0005] Therefore, it is necessary to provide improved technical solutions to overcome the above-mentioned technical problems existing in the prior art. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a control circuit, control method, and switching power supply for a switching power supply, which can achieve rapid current limiting protection for the switching power supply and also improve the output current accuracy of the switching power supply.

[0007] According to a first aspect of this disclosure, a control circuit for a switching power supply is provided, the switching power supply including an N-phase power conversion circuit, where N is an integer greater than or equal to 1, wherein the control circuit includes:

[0008] The current reference signal generation module is configured to perform error integration on the first compensation signal and the first voltage signal to obtain an integrated signal, and to superimpose the integrated signal with the first compensation signal to obtain a current reference signal;

[0009] The control module is configured to obtain control signals for each phase power conversion circuit based on the current reference signal, so as to control each phase power conversion circuit to provide power output to the load.

[0010] The first compensation signal represents the difference between the output feedback signal of the switching power supply and the preset reference voltage, and the first voltage signal represents the average current information of each phase power conversion circuit in the N-phase power conversion circuit.

[0011] Optionally, the current reference signal generation module includes:

[0012] An error integration circuit is configured to integrate the difference between the first compensation signal and the first voltage signal and output the integrated signal.

[0013] A first adder is configured to perform an addition operation on the first compensation signal and the integral signal to generate the current reference signal.

[0014] Optionally, N equals 1, and the first voltage signal characterizes the average output current of the power conversion circuit.

[0015] Optionally, the first voltage signal is obtained in response to sampling the output current of the switching power supply, or in response to averaging the output current of the power conversion circuit after sampling.

[0016] Optionally, the control module is configured to generate a peak current reference signal and / or a valley current reference signal based on the current reference signal, and to obtain the control signal based on the peak current reference signal and / or the valley current reference signal, as well as the inductor current sampling signal of the power conversion circuit, so as to trigger the on / off control of the switching devices in the power conversion circuit.

[0017] Optionally, N is greater than 1, and the first voltage signal characterizes the average current value per phase of the N-phase power conversion circuit.

[0018] Optionally, the first voltage signal is obtained by sampling the output current of the switching power supply and dividing it by N; or by sampling the total current output by the N-phase power conversion circuits connected in parallel, averaging the samples, and dividing them by N.

[0019] Alternatively, it can be obtained by sampling the output current of each phase power conversion circuit in the N-phase power conversion circuit, summing the results, averaging them, and dividing by N.

[0020] Optionally, the control module includes:

[0021] The N-phase control unit corresponds one-to-one with the N-phase power conversion circuit. Each phase control unit in the N-phase control unit is configured to generate a peak current reference signal and / or a valley current reference signal for the corresponding phase power conversion circuit based on the current reference signal, and obtain a control signal based on the peak current reference signal and / or valley current reference signal of the corresponding phase power conversion circuit and the inductor current sampling signal of the corresponding phase power conversion circuit, so as to trigger the on / off control of the switching devices in the corresponding phase power conversion circuit.

[0022] Optionally, the control module includes:

[0023] The current reference signal processing module is configured to generate a peak current reference signal and / or a valley current reference signal based on the current reference signal;

[0024] The N-phase control unit corresponds one-to-one with the N-phase power conversion circuit. Each phase control unit in the N-phase control unit is configured to obtain a control signal based on the peak current reference signal and / or valley current reference signal, as well as the inductor current sampling signal of the corresponding phase power conversion circuit, so as to trigger the on / off control of the switching devices in the corresponding phase power conversion circuit.

[0025] Optionally, N is greater than 1, and the current reference signal generation module includes:

[0026] Each of the N-phase first voltage signal generation units corresponds to one of the N-phase power conversion circuits. Each phase first voltage signal generation unit in the N-phase first voltage signal generation unit is configured to generate the first voltage signal of the corresponding phase power conversion circuit.

[0027] The N-phase current reference signal generation unit corresponds one-to-one with the N-phase power conversion circuit. Each phase current reference signal generation unit in the N-phase current reference signal generation unit is configured to perform error integration on the first compensation signal and the first voltage signal of the corresponding phase power conversion circuit to obtain the integrated signal of the corresponding phase power conversion circuit, and to superimpose the integrated signal of the corresponding phase power conversion circuit with the first compensation signal to obtain the current reference signal of the corresponding phase power conversion circuit.

[0028] The control module includes N-phase control units, each corresponding to one of the N-phase power conversion circuits. Each phase control unit in the N-phase control unit is configured to obtain a control signal for the corresponding phase power conversion circuit based on the current reference signal of the corresponding phase power conversion circuit, so as to control the phase power conversion circuit to provide power output to the load.

[0029] The first voltage signal of each phase power conversion circuit represents the average value of the output current of the corresponding phase power conversion circuit.

[0030] Optionally, each phase current reference signal generation unit in the N-phase current reference signal generation unit includes:

[0031] An error integration circuit is configured to integrate the difference between the first compensation signal and the first voltage signal of the corresponding phase power conversion circuit, and output the integrated signal of the corresponding phase power conversion circuit.

[0032] The first adder is configured to perform an addition operation on the first compensation signal and the integral signal of the corresponding phase power conversion circuit to generate a current reference signal for the corresponding phase power conversion circuit.

[0033] According to a second aspect of this disclosure, another control circuit for a switching power supply is provided, the switching power supply including an N-phase power conversion circuit, where N is an integer greater than or equal to 1, the control circuit including:

[0034] The current reference signal generation module is configured to perform error integration on the first compensation signal and the first voltage signal to obtain an integrated signal, and to obtain a current reference signal based on the integrated signal when the first compensation signal does not reach a preset current limiting threshold, and to obtain a current reference signal based on the first compensation signal when the first compensation signal reaches the preset current limiting threshold.

[0035] The control module is configured to obtain control signals for each phase power conversion circuit based on the current reference signal, so as to control each phase power conversion circuit to provide power output to the load.

[0036] The first compensation signal represents the difference between the output feedback signal of the switching power supply and the preset reference voltage, and the first voltage signal represents the average current information of the power conversion circuit.

[0037] Optionally, when the first compensation signal reaches a preset current limiting threshold, the current reference signal generation module is configured to use the first compensation signal as a current reference signal, or to superimpose the integral signal with the first compensation signal to obtain the current reference signal.

[0038] According to a third aspect of this disclosure, a switching power supply is provided, comprising: an N-phase parallel-coupled power conversion circuit, and any of the control circuits described above.

[0039] According to a fourth aspect of this disclosure, a control method for a switching power supply is provided, the switching power supply including an N-phase power conversion circuit, where N is an integer greater than or equal to 1, the control method comprising:

[0040] Obtain the first compensation signal and the first voltage signal;

[0041] The error is integrated between the first compensation signal and the first voltage signal to obtain the integrated signal;

[0042] The integral signal is superimposed with the first compensation signal to obtain a current reference signal;

[0043] Based on the current reference signal, control signals are obtained for each phase power conversion circuit to control each phase power conversion circuit to provide power output to the load.

[0044] The first compensation signal represents the difference between the output feedback signal of the switching power supply and the preset reference voltage, and the first voltage signal represents the average current information of each phase power conversion circuit in the N-phase power conversion circuit.

[0045] Optionally, the method for obtaining the first compensation signal includes:

[0046] The output voltage of the switching power supply is sampled to obtain a second sampling signal;

[0047] The second sampled signal and the preset reference voltage signal are amplified to obtain an error amplified signal;

[0048] The error amplification signal is compensated to obtain the first compensated signal.

[0049] Optionally, N equals 1, and the method for obtaining the first voltage signal includes:

[0050] The first voltage signal is obtained by sampling the output current of the switching power supply; or

[0051] The first voltage signal is obtained by sampling the output current of the power conversion circuit and averaging the results.

[0052] Optionally, N is greater than 1, and the method for obtaining the first voltage signal includes:

[0053] The first voltage signal is obtained by sampling the output current of the switching power supply and dividing it into N equal parts; or

[0054] The first voltage signal is obtained by sampling the total output current of the N-phase power conversion circuit connected in parallel, averaging the values, and dividing the average into N equal parts; or

[0055] The first voltage signal is obtained by sampling the output current of each phase power conversion circuit in the N-phase power conversion circuit, summing the results, averaging the results, and dividing the results into N equal parts.

[0056] Optionally, N is greater than 1, and the method for obtaining the first voltage signal includes:

[0057] The output current of each phase power conversion circuit is sampled to obtain the sampling signal of each phase power conversion circuit;

[0058] The average value of the sampled signals of each phase power conversion circuit is calculated to obtain the first voltage signal of each phase power conversion circuit.

[0059] According to a fifth aspect of this disclosure, another control method for a switching power supply is provided, the switching power supply including an N-phase power conversion circuit, where N is an integer greater than or equal to 1, the control method comprising:

[0060] Obtain the first compensation signal and the first voltage signal;

[0061] The error is integrated between the first compensation signal and the first voltage signal to obtain the integrated signal;

[0062] Determine whether the first compensation signal reaches a preset current limiting threshold, and if the first compensation signal does not reach the preset current limiting threshold, obtain the current reference signal based on the integral signal; if the first compensation signal reaches the preset current limiting threshold, obtain the current reference signal based on the first compensation signal.

[0063] Based on the current reference signal, control signals are obtained for each phase power conversion circuit to control each phase power conversion circuit to provide power output to the load.

[0064] The first compensation signal represents the difference between the output feedback signal of the switching power supply and the preset reference voltage, and the first voltage signal represents the average current information of each phase power conversion circuit in the N-phase power conversion circuit.

[0065] Optionally, when the first compensation signal reaches a preset current limiting threshold, the first compensation signal is used as a current reference signal, or the integral signal is superimposed with the first compensation signal to obtain the current reference signal.

[0066] The beneficial effects of the present invention include at least the following:

[0067] In this embodiment of the invention, the error between a first compensation signal (characterizing the difference between the output voltage of the switching power supply and a preset reference voltage signal) and a first voltage signal (characterizing the average current value of each phase power conversion circuit) is integrated to obtain the base value of the current reference signal for each phase power conversion circuit. The control of the N-phase power conversion circuit is achieved by superimposing the integrated signal with the first compensation signal. In this process, based on the input characteristics of the integrator in steady state (input is zero) and the response characteristics in fast dynamic state (response speed is slow), the output accuracy of the switching power supply's output current can be improved, and it is beneficial to achieve fast current limiting of the switching power supply's output current.

[0068] On the other hand, the embodiments of the present invention determine whether each phase power conversion circuit has reached a preset current limiting threshold. If it is determined that the threshold has not been reached, the aforementioned integral signal is used as the basis for obtaining the current reference signal of each phase power conversion circuit. If it is determined that the threshold has been reached, the current reference signal is obtained according to the first compensation signal. In this way, each phase power conversion circuit can achieve high-precision current output of the switching power supply based on the integral signal when the preset current limiting threshold has not been reached. When the preset current limiting threshold has been reached, the rapid change of the first compensation signal can be quickly introduced into the current reference signal to achieve rapid current limiting protection. Thus, a good balance between high-precision current output and rapid current limiting protection is achieved.

[0069] It should be noted that the above general description and the following detailed description are exemplary and explanatory only, and do not limit the present invention. Attached Figure Description

[0070] Figure 1 This diagram shows the structure of an existing switching power supply.

[0071] Figure 2 A schematic diagram of the structure of a switching power supply provided according to a first embodiment of the present invention is shown;

[0072] Figure 3 A schematic diagram of the structure of a switching power supply provided according to a second embodiment of the present invention is shown;

[0073] Figure 4 A schematic diagram of the structure of a switching power supply provided according to a third embodiment of the present invention is shown;

[0074] Figure 5 This diagram illustrates the structure of a current reference signal generation module / unit according to an embodiment of the present invention.

[0075] Figure 6 This diagram illustrates the structure of another current reference signal generation module / unit provided according to an embodiment of the present invention;

[0076] Figures 7a to 7c Show each Figure 3 Schematic diagrams of different structures of the first voltage signal generation unit in the middle;

[0077] Figure 8 Show Figure 4 A schematic diagram of the structure of the first voltage signal generation unit;

[0078] Figure 9 A flowchart illustrating a control method for a switching power supply according to a first embodiment of the present invention is shown.

[0079] Figure 10 A flowchart illustrating a control method for a switching power supply according to a second embodiment of the present invention is shown. Detailed Implementation

[0080] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in various forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0081] It should be noted that, in this document, the switching device is a transistor operating in switching mode to provide a current path, including one selected from bipolar transistors or field-effect transistors. The first and second terminals of the switching device are respectively the high-potential terminal and the low-potential terminal on the current path, and the control terminal of the switching device is used to receive a drive signal to control the transistor's on and off states. Furthermore, in this application, the description of the on and off states of the power conversion circuit corresponds to the on and off states of the main switching device in the power conversion circuit that receives the input voltage. For example, turning on the power conversion circuit corresponds to turning on the main switching device in the power conversion circuit to connect the energy storage element in the circuit to the input for charging and energy storage, and to begin providing power output to the load (i.e., generating a corresponding output voltage based on the input voltage); turning off the power conversion circuit corresponds to turning off the main switching device in the power conversion circuit to end the charging and energy storage state of the energy storage element in the circuit, and to stop providing power output to the load.

[0082] Figure 1 A schematic diagram of an existing switching power supply is shown. Figure 1 As shown, the switching power supply 100 includes a control circuit 110, a power conversion circuit 101, and a feedback control circuit 111. The power conversion circuit 101 includes a driver, switching devices T1 and T2, and an inductor Lx. Switching devices T1 and T2 are connected between the input voltage Vin and a reference ground. The first end of the inductor Lx is connected to the intermediate node of switching devices T1 and T2, and the second end is connected to the first end of the output capacitor Cout. The second end of the output capacitor Cout is grounded. The driver in the power conversion circuit 101 receives a control signal, i.e., a pulse width modulation signal PWM1, provided by the controller 110, and controls the corresponding switching device transistor to turn on and off according to the control signal, charging the energy storage element for a corresponding duration to generate an output voltage Vout, and driving the load based on the output capacitor Cout. The control circuit 110 includes a control unit 112, which uses the first compensation signal Vc0 output by the feedback control circuit 111 as a current reference signal, and then controls the on / off state of switching devices T1 and T2 based on the comparison result between its inductor current and the current reference signal Vc0.

[0083] exist Figure 1 In the switching power supply shown, the existing control method makes it difficult to achieve high accuracy of the output current Io, and the current limiting effect is also relatively poor when performing fast overcurrent protection on the switching power supply 100.

[0084] To address the aforementioned problems, this invention improves the control circuit of the switching power supply and proposes a control method for quickly and directly limiting the average current. This method obtains an integral signal by integrating the error between a first compensation signal representing the current reference of the power conversion circuit and a first voltage signal representing the average current information of the power conversion circuit. The control of each phase of the power conversion circuit is achieved through selective processing of this integral signal and the first compensation signal. This allows for rapid current limiting by quickly introducing the rapid change of the first compensation signal into the current reference signal of the corresponding phase power conversion circuit when current limiting is required, while achieving high-precision current output when current limiting is not required. This approach effectively balances high-precision current output with rapid current limiting protection.

[0085] The switching power supply of this invention includes a control circuit (hereinafter referred to as the control circuit) and an N-phase power conversion circuit, where N is a positive integer greater than or equal to 1. The control circuit controls the conduction sequence and charging time of the N-phase power conversion circuits to jointly output an output voltage Vout. The control circuit is coupled to the N-phase power conversion circuits and further includes a current reference signal generation module and a control module. The current reference signal generation module is configured to perform error integration on a first compensation signal and a first voltage signal to obtain an integrated signal, and then superimpose the integrated signal with the first compensation signal to obtain a current reference signal. The control module is configured to obtain a control signal corresponding to each phase power conversion circuit based on the current reference signal to control each phase power conversion circuit to provide power output to the load. The first voltage signal is used to characterize the average current value information of each phase power conversion circuit in the N-phase power conversion circuit.

[0086] Example 1

[0087] In this embodiment, N equals 1. For example... Figure 2 As shown, the switching power supply 200 disclosed in this embodiment includes a power conversion circuit 201 and a control circuit 210. The power conversion circuit 201 has an input terminal coupled to the input voltage and an output terminal coupled to the load to provide power output.

[0088] It should be noted that, although Figure 2 The power conversion circuit 201 shown in the figure can be referenced. Figure 1 The structure of the power conversion circuit 101 in the present invention will be understood. Although the power conversion circuit 201 is described as having a buck topology, the technical solution of the present invention can be adopted for any type of layout design, such as boost, flyback, buck-boost, Cuk, Sepic, and Zeta.

[0089] Control circuit 210 is coupled to power conversion circuit 201. Control circuit 210 is used to adjust the power based on a first compensation signal Vc0 and a first voltage signal (denoted as V). SEN The error integration result of the first voltage signal Vc1 generates a current reference signal Vc1, and the control signal PWM1 of the power conversion circuit 201 is obtained based on the current reference signal Vc1 to control the power conversion circuit 201 to provide power output to the load. SEN The average current value used to characterize the output current of the power conversion circuit 201 can be obtained in response to sampling the output current Iout of the switching power supply 200, or it can be obtained by averaging the output current Io of the power conversion circuit 201 after sampling.

[0090] In this embodiment, the control circuit 210 further includes: a feedback control circuit 211, a first voltage signal generation unit 212, a current reference signal generation module 213, and a control module 214.

[0091] The feedback control circuit 211 has its first input terminal connected to the output terminal of the power conversion circuit 201 to receive a second sampling signal (denoted as FB) representing the output voltage Vout of the switching power supply 200. The second input terminal of the feedback control circuit 211 receives a preset reference voltage signal (denoted as Vref). The output terminal of the feedback control circuit 211 is connected to the current reference signal generation module 213 to output a first compensation signal Vc0 to the current reference signal generation module 213. The first compensation signal Vc0 represents the difference between the second sampling signal FB and the preset reference voltage signal Vref. For example, the second sampling signal FB can be obtained by dividing the output voltage Vout of the switching power supply 200 using a resistor voltage divider sampling unit. In some possible embodiments of the present invention, the feedback control circuit 211 specifically includes an error amplifier circuit and a compensation circuit. The first input terminal of the error amplifier circuit receives the reference voltage signal Vref, the second input terminal receives the second sampling signal FB, and the output terminal of the error amplifier circuit is connected to the compensation circuit and outputs the first compensation signal Vc0.

[0092] Optionally, the first voltage signal generation unit 212 is configured, for example, to sample the output current Iout of the switching power supply 200 from node a2 to obtain the first voltage signal V. SEN Alternatively, for example, the first voltage signal V can be obtained by sampling the output current Io of the power conversion circuit 201 from node a1 and then averaging the samples. SEN .

[0093] Optionally, in some possible embodiments of the present invention, the current reference signal generation module 213 is configured to compare the first compensation signal Vc0 with the first voltage signal V SEN Error integration is performed to obtain an integral signal ΔVc, and the integral signal ΔVc is superimposed with a first compensation signal Vc0 to obtain a current reference signal Vc1. This includes directly using the superposition result of the integral signal ΔVc and the first compensation signal Vc0 as the current reference signal Vc1; or first superimposing the integral signal ΔVc with the first compensation signal Vc0 once, and then superimposing the result of the first superposition with a preset third compensation signal a second time, and finally using the signal after the second superposition as the current reference signal Vc1.

[0094] For example, such as Figure 5As shown, a current reference signal generation module 213 disclosed in this invention specifically includes: an error integration circuit 2131 and a first adder 2132. The error integration circuit 2131 is configured to integrate the first compensation signal Vc0 and the first voltage signal V... SEN The difference is integrated, and the integrated signal ΔVc is output. The first adder 2132 is configured to add the first compensation signal Vc0 and the integrated signal ΔVc to generate a current reference signal Vc1. Exemplarily, the error integration circuit 2131 can be implemented by a combination of a subtractor and an integrator.

[0095] In this embodiment, based on the working principle of the integrator, it is known that during the rapid dynamic changes of the switching power supply 200, the integrator's response is slow, and therefore the integrated signal ΔVc output by the integrator remains approximately constant. Furthermore, when the output current of the power conversion circuit suddenly increases, the output voltage decreases, causing the first compensation signal Vc0 to increase rapidly. If the first compensation signal Vc0 abruptly reaches the current-limiting value, the first adder 2132 can quickly introduce this rapid change in the first compensation signal Vc0 onto the current reference signal Vc1, causing the current reference signal Vc1 to also quickly change to the corresponding current-limiting value. This triggers rapid current limiting of the power conversion circuit 201, ultimately allowing the output current Iout of the switching power supply 200 to be quickly limited to the current value corresponding to the current-limiting value, thus achieving rapid current limiting of the switching power supply output current Iout. Simultaneously, in a steady state, the integrator's input is zero. Therefore, when the switching power supply 200 reaches a steady state, for the power conversion circuit 201, Vc0 equals Vc0. SEN That is, at this time, the first compensation signal Vc0 corresponding to the power conversion circuit 201 corresponds to its average output current Io. Therefore, high-precision control or current limiting of the output current Io of the switching power supply 200 can be achieved by controlling the magnitude of the first compensation signal Vc0 (i.e., controlling the magnitude of the reference voltage signal Vref).

[0096] In some other possible embodiments of the present invention, the current reference signal generation module 213 is configured to compare the first compensation signal Vc0 with the first voltage signal V SENError integration is performed to obtain an integral signal ΔVc. When the first compensation signal Vc0 reaches a preset current limiting threshold (denoted as V1), a current reference signal Vc1 is obtained based on the first compensation signal Vc0, so that the rapid change of the first compensation signal Vc0 is introduced into the current reference signal Vc1, thereby achieving rapid current limiting. When the first compensation signal Vc0 does not reach the preset current limiting threshold V1, the current reference signal Vc1 is obtained based on the integral signal ΔVc, for example, by superimposing the integral signal ΔVc with a preset second compensation signal to obtain the current reference signal Vc1. Optionally, when the first compensation signal Vc0 reaches the preset current limiting threshold V1, the current reference signal generation module 213 may, for example, directly use the first compensation signal Vc0 as the current reference signal Vc1, or superimpose the integral signal ΔVc with the first compensation signal Vc0 to obtain the current reference signal Vc1.

[0097] For example, such as Figure 6 As shown, based on another current reference signal generation module 213 disclosed in this invention, it specifically includes: an error integration circuit 2131, a first adder 2132, a comparator circuit 2134, and a selector 2133. The error integration circuit 2131 and the first adder 2132 can be referenced to... Figure 5 The description is as follows. The comparator circuit 2134 is configured to compare the first compensation signal Vc0 with a preset current limiting threshold V1, and output a corresponding selection signal based on the comparison result. The first input terminal of the selector 2133 receives the integral signal ΔVc, and the second input terminal of the selector 2133 receives either the output signal of the first adder 2132 or the first compensation signal Vc0 (the first adder 2132 can be omitted when the second input terminal of the selector 2133 receives the first compensation signal Vc0). The control terminal of the selector 2133 receives the selection signal, and the selector 2133 is configured to select and output the signal received at its first input terminal and the signal received at its second input terminal based on the selection signal.

[0098] This embodiment introduces a judgment on whether the power conversion circuit 201 has reached a preset current limiting threshold. If it is determined that the threshold has not been reached, the integral signal is used as the basis for obtaining the current reference signal of each phase power conversion circuit. This allows each phase power conversion circuit to achieve high-precision current output of the switching power supply based on the integral signal when the preset current limiting threshold has not been reached. If it is determined that the threshold has been reached, the current reference signal is obtained based on the first compensation signal. The rapid change of the first compensation signal can be quickly introduced into the current reference signal to achieve fast current limiting protection. In this way, both high-precision current output and fast current limiting protection are well achieved.

[0099] Continue to refer to Figure 2In this embodiment, the control module 214 is configured to generate a peak current reference signal and / or a valley current reference signal based on the current reference signal Vc1 generated by the current reference signal generation module 213 to control the peak and / or valley values ​​of the inductor current of the power conversion circuit 201, and obtain a control signal PWM1 based on the peak current reference signal and / or valley current reference signal and the inductor current sampling signal of the power conversion circuit 201, so as to trigger the on / off control of the switching devices (including switching devices T1 and T2) in the power conversion circuit 201, thereby controlling the power conversion circuit 201 to provide power output to the load.

[0100] Example 2

[0101] In this embodiment, N is greater than 1. For example... Figure 3 As shown, the switching power supply 300 disclosed in this embodiment includes a switching power supply control circuit 310 and an N-phase parallel coupled power conversion circuit 301-30N.

[0102] Each phase power conversion circuit in the N-phase power conversion circuits 301-30N can be understood by referring to the structural description of the power conversion circuit 201 in the aforementioned embodiment 1, and will not be repeated here.

[0103] In this embodiment, the control circuit 310 is coupled to the N-phase power conversion circuits 301-30N respectively. The control circuit 310 is used to adjust the first compensation signal Vc0 and the first voltage signal V. SEN The error integration result generates a current reference signal Vc1, and based on this current reference signal Vc1, control signals PWM1-PWMN corresponding to each phase power conversion circuit in the N-phase power conversion circuits 201-20N are obtained to control each phase power conversion circuit to provide power output to the load. The first voltage signal Vc1... SEN The average current value per phase of the N-phase power conversion circuits 301-30N can be obtained by sampling the output current of the switching power supply 300 and dividing it by N; or it can be obtained by sampling the total output current I of the N-phase power conversion circuits 301-30N connected in parallel. SUM The sampled value is then averaged and divided by N; alternatively, it can be obtained by sampling the output current of each phase power conversion circuit in the N-phase power conversion circuits 301-30N, summing the results, averaging the results, and dividing by N.

[0104] In this embodiment, the control circuit 310 further includes: a feedback control circuit 311, a first voltage signal generation unit 312, a current reference signal generation module 313, and a control module 314.

[0105] The function and structure of the feedback control circuit 311 can be understood by referring to the description of the feedback control circuit 211 in the aforementioned embodiment 1, and will not be repeated here.

[0106] Optionally, the first voltage signal generation unit 312 in this embodiment can be configured to sample the output current Iout of the switching power supply 300 to obtain a first sampling signal, and divide the first sampling signal by N to generate a first voltage signal V. SEN For example, such as Figure 7a As shown, the first voltage signal generation unit 312 further includes a first current sampling circuit 3121 and a first division circuit 3122. The first current sampling circuit 3121 is configured to sample the output current I of the switching power supply 300 from node b3 based on the sampling resistor. out A first sampled signal is obtained by sampling. The first division circuit 3122 is configured to perform a division operation between the first sampled signal and N to output a first voltage signal V. SEN It is understood that in this embodiment, the first voltage signal V is obtained from the first sampling signal. SEN Besides using a division circuit, other methods such as a voltage divider circuit can also be used, as long as the final generated first voltage signal V is achieved. SEN The numerical value should be equal to one-Nth of the first sampled signal.

[0107] Optionally, the first voltage signal generation unit 312 in this embodiment can also be configured to output the total current I after parallel connection with the N-phase power conversion circuit. SUM The first voltage signal V is generated by sampling, averaging, and dividing by N. SEN For example, such as Figure 7b As shown, the first voltage signal generation unit 312 further includes: a second current sampling circuit 3123, a first averaging circuit 3124, and a second division circuit 3125. The second current sampling circuit 3123 is configured to output the total current I based on the sampling resistor connected in parallel with the N-phase power conversion circuit from node b2. SUM Sampling is performed. The first averaging circuit 3124 is configured to average the sampled signal output from the second current sampling circuit 3123, and the second division circuit 3125 is configured to perform a division operation on the output signal of the first averaging circuit 3124 to output a first voltage signal V. SEN .

[0108] Optionally, the first voltage signal generation unit 312 in this embodiment can also be configured to sample the output current of each phase power conversion circuit in the N-phase power conversion circuit and sequentially perform summation, averaging, and division by N to generate the first voltage signal V. SEN For example, such as Figure 7cAs shown, the first voltage signal generation unit 312 further includes: a plurality of third current sampling circuits 3126, a second adder 3317, a second averaging circuit 3128, and a third division circuit 3129. The plurality of third current sampling circuits 3126 are configured to sample the output currents Io1 to IoN of each phase power conversion circuit in the N-phase power conversion circuit from nodes b11 to b1N according to the sampling resistors. The second adder circuit 3127 is configured to sum the plurality of sampled signals from the plurality of third current sampling circuits 3126. The second averaging circuit 3128 is configured to average the output signal of the second adder 3127, and the third division circuit 3129 is configured to divide the output signal of the second averaging circuit 3128 to output a first voltage signal V. SEN It is understandable that the first voltage signal generation unit 312 performs the above-mentioned processing on the output current of each phase power conversion circuit in the sampled N-phase power conversion circuit to obtain the first voltage signal V. SEN In addition to the above-described processing order, the first voltage signal V can also be generated by sequentially performing summation, division by N, and averaging. SEN Alternatively, the output current of each phase power conversion circuit can be sampled and averaged separately, and then the average output current of each phase power conversion circuit can be summed and divided by N to generate the first voltage signal V. SEN This invention does not limit the scope of the invention. Furthermore, in specific implementations, only corresponding modifications are required. Figure 7c The connection relationship between the multiple third current sampling circuits 3126, the second adder 3317, the second averaging circuit 3128, and the third division circuit 3129 can be determined.

[0109] In this embodiment, the function and structure of the current reference signal generation module 313 can be understood by referring to the description of the current reference signal generation module 213 in the aforementioned embodiment 1, and will not be repeated here.

[0110] Continue to refer to Figure 3 The control module 314 includes N-phase control units 3141-314N, which correspond one-to-one with N-phase power conversion circuits 301-30N. The control module 314 is configured to obtain control signals PWM1-PWMN for each phase power conversion circuit based on the current reference signal Vc1 generated by the current reference signal generation module 313, so as to control each phase power conversion circuit to provide power output to the load.

[0111] In this embodiment, the current reference signal Vc1 can be processed and converted into a peak current reference signal and / or a valley current reference signal that controls the peak and / or valley values ​​of the inductor current of the corresponding phase power conversion circuit.

[0112] Optionally, in some possible embodiments of the present invention, the conversion processing of the current reference signal Vc1 is performed separately by each phase control unit. That is, each phase control unit of the N-phase control units 3141-314N is configured to generate a peak current reference signal and / or a valley current reference signal for the corresponding phase power conversion circuit based on the current reference signal Vc1, and obtain a control signal based on the peak current reference signal and / or valley current reference signal of the corresponding phase power conversion circuit, and the inductor current sampling signal of the corresponding phase power conversion circuit, so as to trigger the on / off control of the switching devices in the corresponding phase power conversion circuit. For example, taking the Mth phase control unit 314M in the N-phase control units 3141-314N as an example, the Mth phase control unit 314M can be configured to generate an Mth peak current reference signal and / or an Mth valley current reference signal based on the current reference signal Vc1, and obtain an Mth control signal based on the Mth peak current reference signal and / or the Mth valley current reference signal, and the Mth inductor current sampling signal, to trigger the on / off control of the switching devices in the Mth phase power conversion circuit. Here, M is any integer from 1 to N, and the Mth inductor current sampling signal characterizes the inductor current of the Mth phase power conversion circuit 20M. This facilitates precise control of each phase power conversion circuit. Furthermore, based on the structure and working principle of the control module 314 at this time, it is also beneficial to achieve current sharing control of the N-phase power conversion circuits 301-30N in the switching power supply 300.

[0113] In some other possible embodiments of the present invention, the control module 314 further includes a current reference signal processing module, which performs the conversion processing of the current reference signal Vc1 uniformly. That is, the current reference signal processing module can generate a peak current reference signal and / or a valley current reference signal based on the current reference signal Vc1. Each phase control unit in the N-phase control units 3141-314N is configured to obtain a control signal based on the peak current reference signal and / or valley current reference signal generated by the current reference signal processing module, and the inductor current sampling signal of the corresponding phase power conversion circuit, so as to trigger the on / off control of the switching devices in the corresponding phase power conversion circuit. For example, taking the Mth phase control unit 214M in the N-phase control units 3141-314N as an example, the Mth phase control unit 314M can be configured to obtain the Mth control signal based on the peak current reference signal and / or valley current reference signal generated by the current reference signal processing module, and the Mth inductor current sampling signal, so as to trigger the on / off control of the switching devices in the Mth phase power conversion circuit 20M. Where M is any integer from 1 to N, and the sampling signal of the Mth inductor current represents the magnitude of the inductor current of the Mth phase power conversion circuit.

[0114] In this embodiment, since the current reference signal Vc1 output by the current reference signal generation module 313 is simultaneously output to each control unit, only one current reference signal generation module 313 is needed in this invention to achieve adaptive adjustment of the current reference signal corresponding to the power conversion circuit of all phases, and the circuit structure is simple.

[0115] Furthermore, the switching power supply 300 also includes multiple drive units. These drive units are configured to generate drive signals based on the control signals PWM1-PWMN generated by the N-phase control units 3141-314N in the control circuit 310, and send the drive signals to the control terminals of the switching devices in the corresponding phase power conversion circuits. Exemplarily, the multiple drive units are integrated into each phase power conversion circuit, or the multiple drive units are integrated into the control circuit 310, with each drive unit corresponding to a control unit.

[0116] Example 3

[0117] In this embodiment, N is greater than 1. For example... Figure 4 As shown, the switching power supply 400 disclosed in this embodiment includes a switching power supply control circuit 410 and an N-phase parallel coupled power conversion circuit 401-40N.

[0118] The power conversion circuits of each phase in the N-phase power conversion circuits 401-40N can be understood by referring to the structural description of the power conversion circuit 201 in the aforementioned embodiment 1, and will not be repeated here.

[0119] In this embodiment, the control circuit 410 is coupled to the N-phase power conversion circuits 401-40N respectively. The control circuit 410 is used to adjust the first compensation signal Vc0 and the first voltage signal V corresponding to each phase power conversion circuit. SEN1 ~V SENN The error integration result generates current reference signals Vc1~VcN for each phase power conversion circuit, and based on these, control signals PWM1-PWMN for each phase power conversion circuit in the N-phase power conversion circuits 401-40N are obtained to control each phase power conversion circuit to provide power output to the load. The first voltage signal corresponding to each phase power conversion circuit represents the average value of the output current of the corresponding phase power conversion circuit, and can be obtained, for example, by sampling and averaging the output current of the corresponding phase power conversion circuit.

[0120] In this embodiment, the control circuit 410 further includes: a feedback control circuit 411, a current reference signal generation module 413, and a control module 414.

[0121] The function and structure of the feedback control circuit 411 can be understood by referring to the description of the feedback control circuit 211 in the aforementioned embodiment 1, and will not be repeated here.

[0122] In this embodiment, the current reference signal generation module 413 further includes N-phase first voltage signal generation units 4121~412N and N-phase current reference signal generation units 4131~413N.

[0123] Among them, the N-phase first voltage signal generation units 4121~412N correspond one-to-one with the N-phase power conversion circuits 401~40N, and each phase first voltage signal generation unit in the N-phase first voltage signal generation units 4121~412N is configured to generate the first voltage signal of the corresponding phase power conversion circuit.

[0124] For example, taking the first phase first voltage signal generation unit 4121 as an example, such as Figure 8 As shown, the first voltage signal generation unit 4121 corresponding to the first phase power conversion circuit 401 further includes: a fourth current sampling circuit 41211 and a third averaging circuit 41212. The fourth current sampling circuit 41211 is configured to sample the output current Io1 of the first phase power conversion circuit 401 based on a sampling resistor. The third averaging circuit 41212 is configured to perform averaging processing on the sampled signal obtained by the fourth current sampling circuit 41211 to output the first voltage signal V corresponding to the first phase power conversion circuit 401. SEN1 Alternatively, the third averaging circuit 41212 can be implemented, for example, by an RC filter circuit.

[0125] The N-phase current reference signal generation units 4131~413N correspond one-to-one with the N-phase power conversion circuits 401~40N and the N-phase first voltage signal generation units 4121~412N. Each phase current reference signal generation unit in the N-phase current reference signal generation units 4131~413N is configured to perform error integration on the first compensation signal Vc0 and the first voltage signal of the corresponding phase power conversion circuit to obtain the integrated signal of the corresponding phase power conversion circuit, and then superimpose the integrated signal of the corresponding phase power conversion circuit with the first compensation signal Vc0 to obtain the current reference signal of the corresponding phase power conversion circuit. For example, taking the M-phase current reference signal generation unit 413M in the N-phase current reference signal generation units 4131~413N as an example, the M-phase current reference signal generation unit 413M can be configured to perform error integration on the first compensation signal Vc0 and the first voltage signal Vc0 of the corresponding M-phase power conversion circuit. SENMError integration is performed to obtain the integrated signal ΔVcM corresponding to the M-th phase power conversion circuit 40M. The integrated signal ΔVcM corresponding to the M-th phase power conversion circuit 40M is then superimposed with the first compensation signal Vc0 to obtain the current reference signal VcM corresponding to the M-th phase power conversion circuit 40M. Here, M is any integer from 1 to N.

[0126] Furthermore, the circuit structure of each phase current reference signal generation unit in the N-phase current reference signal generation units 4131~413N can be understood by referring to the description of the current reference signal generation module 213 in the aforementioned embodiment 1, and will not be repeated here.

[0127] Continue to refer to Figure 4 The control module 314 includes N-phase control units 4141-414N, which correspond one-to-one with N-phase power conversion circuits 401-40N. Each phase control unit in the N-phase control units 4141-414N is configured to obtain the control signal of the corresponding phase power conversion circuit according to the current reference signal of the corresponding phase power conversion circuit, so as to control each phase power conversion circuit to provide power output to the load.

[0128] In this embodiment, the function and circuit structure of each phase control unit in the N-phase control unit 4141-414N can be understood by referring to the description of control module 214 in the aforementioned embodiment 1, and will not be repeated here.

[0129] Furthermore, the switching power supply 400 also includes multiple drive units. These drive units are configured to generate drive signals based on the control signals PWM1-PWMN generated by the N-phase control units 4141-414N in the control circuit 410, and send the drive signals to the control terminals of the switching devices in the corresponding phase power conversion circuits. Exemplarily, the multiple drive units are integrated into each phase power conversion circuit, or the multiple drive units are integrated into the control circuit 410, with each drive unit corresponding to a control unit.

[0130] It is understood that, according to the working principle of the integrator in the N-phase current reference signal generation unit 4131~413N in this embodiment, when the switching power supply 400 reaches a steady state, the average value of the output current corresponding to each phase power conversion circuit is equal. That is to say, in addition to achieving the beneficial effects shown in Embodiment 1, the switching power supply 400 in this embodiment can also achieve current sharing control of the N-phase power conversion circuits 401~40N in the switching power supply 400.

[0131] Furthermore, the present invention also discloses a control method for a switching power supply. This control method can be applied to a single-phase switching power supply (N equals 1) as shown in Embodiment 1 above, and can also be applied to a multi-phase switching power supply (N greater than 1) as shown in Embodiment 2 or Embodiment 3 above. The method includes executing steps S11 to S14, as follows: Figure 9 As shown; or execute steps S21 to S24, as follows. Figure 10 As shown.

[0132] In step S11 or step S21, a first compensation signal and a first voltage signal are obtained. The first voltage signal is used to characterize the average current information of each phase power conversion circuit in the N-phase power conversion circuit.

[0133] In this embodiment, the method for obtaining the first compensation signal includes: sampling the output voltage of the switching power supply to obtain a second sampling signal; amplifying the second sampling signal and a preset reference voltage signal to obtain an error amplification signal; and compensating the error amplification signal to obtain the first compensation signal. The first compensation signal is used to characterize the difference between the output feedback signal of the switching power supply and the preset reference voltage signal.

[0134] Meanwhile, in the first embodiment of the present invention, N equals 1, and the method for obtaining the first voltage signal includes: sampling the output current of the switching power supply to obtain the first voltage signal; or sampling the output current of the power conversion circuit and averaging the results to obtain the first voltage signal.

[0135] In the second embodiment of the present invention, N is greater than 1. The method for obtaining the first voltage signal includes: sampling the output current of the switching power supply and dividing it into N equal parts to obtain the first voltage signal; or sampling the total output current of the N-phase power conversion circuits connected in parallel, calculating the average value, and dividing it into N equal parts to obtain the first voltage signal; or sampling the output current of each phase power conversion circuit in the N-phase power conversion circuit, summing the results, calculating the average value, and dividing it into N equal parts to obtain the first voltage signal.

[0136] In the third embodiment of the present invention, N is greater than 1. The method for obtaining the first voltage signal includes: sampling the output current of each phase power conversion circuit to obtain the sampling signal of each phase power conversion circuit; and averaging the sampling signal of each phase power conversion circuit to obtain the first voltage signal of each phase power conversion circuit.

[0137] In step S12 or step S22, the error is integrated between the first compensation signal and the first voltage signal to obtain the integrated signal.

[0138] In step S13, the integral signal and the first compensation signal are superimposed to obtain the current reference signal.

[0139] In step S23, it is determined whether the first compensation signal reaches the preset current limiting threshold. If the first compensation signal does not reach the preset current limiting threshold, a current reference signal is obtained based on the integral signal. If the first compensation signal reaches the preset current limiting threshold, a current reference signal is obtained based on the first compensation signal, for example, the first compensation signal is used as the current reference signal, or the integral signal is superimposed with the first compensation signal to obtain the current reference signal.

[0140] In step S14 or step S24, the control signal for each phase power conversion circuit is obtained based on the current reference signal.

[0141] In practice, the specific implementation of each step in the control method of the switching power supply described above can be found in the aforementioned embodiments of the switching power supply, and will not be repeated here.

[0142] In summary, the embodiments of the present invention obtain the basic value of the current reference signal of each phase power conversion circuit by integrating the error between the first compensation signal, which represents the difference between the output voltage of the switching power supply and the preset reference voltage signal, and the first voltage signal, which represents the average current value of each phase power conversion circuit. The control of the N-phase power conversion circuit is achieved by superimposing the integrated signal with the first compensation signal. In this process, based on the input characteristics of the integrator in steady state (input is zero) and the response characteristics in fast dynamic state (response speed is slow), the output accuracy of the output current of the switching power supply can be improved and it is beneficial to achieve fast current limiting of the output current of the switching power supply.

[0143] On the other hand, the embodiments of the present invention determine whether each phase power conversion circuit has reached a preset current limiting threshold. If it is determined that the threshold has not been reached, the aforementioned integral signal is used as the basis for obtaining the current reference signal of each phase power conversion circuit. If it is determined that the threshold has been reached, the current reference signal is obtained according to the first compensation signal. In this way, each phase power conversion circuit can achieve high-precision current output of the switching power supply based on the integral signal when the preset current limiting threshold has not been reached. When the preset current limiting threshold has been reached, the rapid change of the first compensation signal can be quickly introduced into the current reference signal to achieve rapid current limiting protection. Thus, a good balance between high-precision current output and rapid current limiting protection is achieved.

[0144] Finally, it should be noted that the above embodiments are merely examples for clearly illustrating the present invention and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A control circuit for a switching power supply, the switching power supply comprising an N-phase power conversion circuit, where N is an integer greater than or equal to 1, wherein, The control circuit includes: The current reference signal generation module is configured to perform error integration on the first compensation signal and the first voltage signal to obtain an integrated signal, and to obtain a current reference signal based on the integrated signal when the first compensation signal does not reach a preset current limiting threshold, and to obtain a current reference signal based on the first compensation signal when the first compensation signal reaches the preset current limiting threshold. The control module is configured to obtain control signals for each phase power conversion circuit based on the current reference signal, so as to control each phase power conversion circuit to provide power output to the load. The first compensation signal represents the difference between the output feedback signal of the switching power supply and the preset reference voltage, and the first voltage signal represents the average current information of each phase power conversion circuit in the N-phase power conversion circuit.

2. The control circuit according to claim 1, wherein, The current reference signal generation module includes: An error integration circuit is configured to integrate the difference between the first compensation signal and the first voltage signal and output the integrated signal. A first adder is configured to perform an addition operation on the first compensation signal and the integral signal to generate the current reference signal when the first compensation signal reaches a preset current limiting threshold.

3. The control circuit according to claim 1, wherein, N equals 1, and the first voltage signal represents the average output current of the power conversion circuit.

4. The control circuit according to claim 3, wherein, The first voltage signal is obtained in response to sampling the output current of the switching power supply, or in response to averaging the output current of the power conversion circuit after sampling.

5. The control circuit according to claim 3, wherein, The control module is configured to generate a peak current reference signal and / or a valley current reference signal based on the current reference signal, and to obtain the control signal based on the peak current reference signal and / or the valley current reference signal, as well as the inductor current sampling signal of the power conversion circuit, so as to trigger the on / off control of the switching devices in the power conversion circuit.

6. The control circuit according to claim 1, wherein, N is greater than 1, and the first voltage signal represents the average current value of each phase power conversion circuit in the N-phase power conversion circuit.

7. The control circuit according to claim 6, wherein, The first voltage signal is obtained by sampling the output current of the switching power supply and dividing it by N; Alternatively, it can be obtained by sampling the total current output after the N-phase power conversion circuit is connected in parallel, averaging the results and dividing by N; Alternatively, it can be obtained by sampling the output current of each phase power conversion circuit in the N-phase power conversion circuit, summing the results, averaging them, and dividing by N.

8. The control circuit according to claim 6, wherein, The control module includes: The N-phase control unit corresponds one-to-one with the N-phase power conversion circuit. Each phase control unit in the N-phase control unit is configured to generate a peak current reference signal and / or a valley current reference signal for the corresponding phase power conversion circuit based on the current reference signal, and obtain a control signal based on the peak current reference signal and / or valley current reference signal of the corresponding phase power conversion circuit and the inductor current sampling signal of the corresponding phase power conversion circuit, so as to trigger the on / off control of the switching devices in the corresponding phase power conversion circuit.

9. The control circuit according to claim 6, wherein, The control module includes: The current reference signal processing module is configured to generate a peak current reference signal and / or a valley current reference signal based on the current reference signal; The N-phase control unit corresponds one-to-one with the N-phase power conversion circuit. Each phase control unit in the N-phase control unit is configured to obtain a control signal based on the peak current reference signal and / or valley current reference signal, as well as the inductor current sampling signal of the corresponding phase power conversion circuit, so as to trigger the on / off control of the switching devices in the corresponding phase power conversion circuit.

10. The control circuit according to claim 1, wherein, N is greater than 1, and the current reference signal generation module includes: Each of the N-phase first voltage signal generation units corresponds to one of the N-phase power conversion circuits. Each phase first voltage signal generation unit in the N-phase first voltage signal generation unit is configured to generate the first voltage signal of the corresponding phase power conversion circuit. Each of the N-phase current reference signal generation units corresponds one-to-one with the N-phase power conversion circuit. Each phase current reference signal generation unit in the N-phase current reference signal generation unit is configured to perform error integration on the first compensation signal and the first voltage signal of the corresponding phase power conversion circuit to obtain the integrated signal of the corresponding phase power conversion circuit. If the first compensation signal does not reach the preset current limiting threshold, the current reference signal of the corresponding phase power conversion circuit is obtained based on the integrated signal of the corresponding phase power conversion circuit. If the first compensation signal reaches the preset current limiting threshold, the current reference signal of the corresponding phase power conversion circuit is obtained based on the first compensation signal. The control module includes N-phase control units, each corresponding to one of the N-phase power conversion circuits. Each phase control unit in the N-phase control unit is configured to obtain a control signal for the corresponding phase power conversion circuit based on the current reference signal of the corresponding phase power conversion circuit, so as to control the phase power conversion circuit to provide power output to the load. The first voltage signal of each phase power conversion circuit represents the average value of the output current of the corresponding phase power conversion circuit.

11. The control circuit according to claim 10, wherein, Each phase current reference signal generation unit in the N-phase current reference signal generation unit includes: An error integration circuit is configured to integrate the difference between the first compensation signal and the first voltage signal of the corresponding phase power conversion circuit, and output the integrated signal of the corresponding phase power conversion circuit. The first adder is configured to perform an addition operation on the first compensation signal and the integral signal of the corresponding phase power conversion circuit, so as to generate a current reference signal of the corresponding phase power conversion circuit when the first compensation signal reaches a preset current limiting threshold.

12. The control circuit according to claim 1, wherein, When the first compensation signal reaches a preset current limiting threshold, the current reference signal generation module is configured to use the first compensation signal as a current reference signal, or to superimpose the integral signal with the first compensation signal to obtain the current reference signal.

13. The control circuit according to claim 12, wherein, The current reference signal generation module includes: An error integration circuit is configured to integrate the difference between the first compensation signal and the first voltage signal and output the integrated signal. The first adder is configured to perform an addition operation on the first compensation signal and the integral signal; The comparison circuit is configured to compare the first compensation signal with a preset current limiting threshold and output a corresponding selection signal based on the comparison result. The selector has a first input terminal receiving the integral signal, a second input terminal receiving the output signal of the first adder or the first compensation signal, and a control terminal receiving the selection signal. The selector is configured to select and output the signal received at the first input terminal and the signal received at the second input terminal according to the selection signal to generate the current reference signal.

14. A switching power supply, wherein, The switching power supply includes: The control circuit as described in any one of claims 1-13.

15. A control method for a switching power supply, the switching power supply comprising an N-phase power conversion circuit, where N is an integer greater than or equal to 1, wherein... The control method includes: Obtain the first compensation signal and the first voltage signal; The error is integrated between the first compensation signal and the first voltage signal to obtain the integrated signal; Determine whether the first compensation signal reaches a preset current limiting threshold, and if the first compensation signal does not reach the preset current limiting threshold, obtain a current reference signal based on the integral signal; if the first compensation signal reaches the preset current limiting threshold, obtain a current reference signal based on the first compensation signal. Based on the current reference signal, control signals are obtained for each phase power conversion circuit to control each phase power conversion circuit to provide power output to the load. The first compensation signal represents the difference between the output feedback signal of the switching power supply and the preset reference voltage, and the first voltage signal represents the average current information of each phase power conversion circuit in the N-phase power conversion circuit.

16. The control method according to claim 15, wherein, Methods for obtaining the first compensation signal include: The output voltage of the switching power supply is sampled to obtain a second sampling signal; The second sampled signal and the preset reference voltage signal are amplified to obtain an error amplified signal; The error amplification signal is compensated to obtain the first compensated signal.

17. The control method according to claim 15, wherein, The methods for obtaining the first voltage signal when N equals 1 include: The first voltage signal is obtained by sampling the output current of the switching power supply; or The first voltage signal is obtained by sampling the output current of the power conversion circuit and averaging the results.

18. The control method according to claim 15, wherein, The methods for obtaining the first voltage signal when N is greater than 1 include: The first voltage signal is obtained by sampling the output current of the switching power supply and dividing it into N equal parts; or The first voltage signal is obtained by sampling the total output current of the N-phase power conversion circuit connected in parallel, averaging the values, and dividing them into N equal parts; or The first voltage signal is obtained by sampling the output current of each phase power conversion circuit in the N-phase power conversion circuit, summing the results, averaging the results, and dividing the results into N equal parts.

19. The control method according to claim 15, wherein, The methods for obtaining the first voltage signal when N is greater than 1 include: The output current of each phase power conversion circuit is sampled to obtain the sampling signal of each phase power conversion circuit; The average value of the sampled signals of each phase power conversion circuit is calculated to obtain the first voltage signal of each phase power conversion circuit.

20. The control method according to claim 15, wherein, When the first compensation signal reaches a preset current limiting threshold, the first compensation signal is used as a current reference signal, or the integral signal is superimposed on the first compensation signal to obtain the current reference signal.

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