CN113507208B - Polyphase series capacitor DC-DC converter and control method - Google Patents

Abstract

A multiphase series capacitor dc-dc converter comprising: the power stage circuit is used for converting input direct-current voltage into stable direct-current voltage required by a load, and at least comprises two phase inductors, phase difference of preset intervals exists between currents of the two phase inductors and is used for sequentially and alternately charging the load, a bidirectional switch is arranged between every two adjacent phase inductors, and when the bidirectional switch is switched on, the corresponding two phase inductors simultaneously charge the load; and the load transient response circuit is used for controlling the conduction of at least one bidirectional switch when the forward jump of the load transient occurs, so that at least two phases of inductors charge the load at the same time, and the transient change of the load is responded quickly. The disclosure also provides a control method of the converter, which can realize quick response to load transient change.

Description

Polyphase series capacitor DC-DC converter and control method

technical field

The present disclosure relates to the field of electronic technology, and in particular, to a multi-phase series capacitor DC-DC converter and a control method.

Background technique

Existing multiphase series capacitor DC-DC converters are usually optimized for the control loop to improve the load transient response speed, but the load transient response speed is still limited by the rising slope of the inductor current. The traditional transient enhancement technology improves the rising slope of the inductor current by increasing the switching frequency. However, the increase in the switching frequency further compresses the on-time of the power tube, which poses a very high challenge to the design of the control and drive circuits; the increase in the switching frequency greatly increases. The switching loss of the power tube deteriorates the conversion efficiency. In order to avoid the overlap of the on-time of the multi-phase power tubes, the control signals of the power tubes need to maintain a fixed phase difference of 360°/N. The N-phase inductor current cannot be used to charge the load at the same time, and the load transient response speed is limited.

SUMMARY OF THE INVENTION

In view of the above problems, the present invention provides a multi-phase series capacitor DC-DC converter and a control method to at least partially solve the above technical problems.

One aspect of the present disclosure provides a multi-phase series capacitor DC-DC converter, characterized by comprising: a power stage circuit for converting an input DC voltage into a stable DC voltage required by a load, wherein the power The stage circuit includes at least two-phase inductors, and there is a preset interval phase difference between the inductor currents of each phase, which is used to charge the load alternately in turn, and a bidirectional switch is provided between each adjacent two-phase inductors. When the bidirectional switch is turned on, the corresponding two-phase inductance simultaneously charges the load; the load transient response circuit is used to control at least one of the bidirectional switches to be turned on when a load transient forward jump occurs, so that at least one of the bidirectional switches is turned on. The two-phase inductance simultaneously charges the load to quickly respond to transient changes in the load.

Optionally, the load transient response circuit includes: an error amplifier for calculating an error between the output voltage of the power stage circuit and a reference voltage to obtain an error signal; a transient detection circuit for calculating the error according to the error The signal judges whether a transient forward jump occurs in the load; the transient enhancement logic circuit is used to generate a control signal for controlling the conduction of the bidirectional switch when the detected load has a transient forward jump; the drive circuit uses and controlling at least one of the bidirectional switches to be turned on according to the control signal.

Optionally, when a load transient forward jump occurs, after at least one of the bidirectional switches is turned on, the two-phase inductors connected to the turned on bidirectional switches are connected in parallel.

Optionally, the load transient response circuit further includes: an on-time generation circuit for generating control signals for the power tubes of the circuits where the inductances of each phase are located according to the error signals, and each of the control signals is used to control each The circuit where the phase inductance is located is turned on, so that the inductances of each phase alternately charge the load; the drive circuit is also used for, when no transient forward jump of the load occurs, according to the control signal of each phase , controlling the power switch arranged on the circuit where the inductors of each phase are located, so that the inductors of each phase alternately charge the load.

Optionally, the sub-circuit where the inductor of at least one phase is located in the power stage circuit includes: a power switch AH, a power switch AL and a filter inductor L _b , which are connected in sequence; the sub-circuit where the inductor of another at least one phase adjacent to the inductor is located. The circuit includes: a power switch BH, a capacitor _CF , a power switch BL and _a filter inductor La, which are connected in sequence; wherein, the input ends of the power switch AH and the capacitor _CF are both connected to the power switch BH, and the power switch BH , AH are respectively used to control the voltage input of the corresponding sub-circuits; the output ends of the filter inductance L _b and the filter inductance L _a are connected to the output port of the power stage circuit; the filter inductance L _b and the filter The bidirectional switch is provided between the input ports of the inductor La _; the output port of the power stage circuit is also provided with a grounded filter capacitor C.

Optionally, after a load transient forward jump occurs, the drive circuit is further configured to connect the power switch BL, the power switch BL, the power switch on the two-phase sub-circuit connected to at least one of the two-way switches that are turned on. AH and the power switch AL are closed, and the power switch BH is driven to generate a voltage input pulse in response to the load transient forward jump.

Another aspect of the present disclosure provides a control method, which is applied to the multi-phase series capacitor DC-DC converter according to the first aspect, comprising: when a transient forward jump of a load is detected, controlling a power stage circuit The bidirectional switches between at least two adjacent inductors are turned on, so that the at least two adjacent inductors charge the load at the same time, so as to quickly respond to the transient change of the load.

Optionally, the method further includes: when the load is working normally, controlling the bidirectional switch to be turned off, and controlling the inductance of each phase to charge the load alternately in turn.

Optionally, when detecting that a transient forward jump occurs in the load, the method further includes: connecting the power switch BL and the power switch on the two-phase sub-circuit connected to at least one of the two-way switches that are turned on in the power stage circuit. AH, the power switch AL are closed, and the power switch BH is driven to generate a voltage input pulse in response to the load transient forward jump.

Optionally, the controlling the conduction of bidirectional switches between at least two adjacent inductors in the power stage circuit when a transient forward jump occurs in the detected load includes: calculating the output voltage of the power stage circuit and the reference The error between the voltages is obtained to obtain an error signal; according to the error signal, it is judged whether the load has a transient forward jump; when the detected load has a transient forward jump, a control to control the conduction of the bidirectional switch is generated. signal; controlling at least one of the bidirectional switches to conduct according to the control signal.

The above-mentioned at least one technical solution adopted in the embodiments of the present disclosure can achieve the following beneficial effects:

The multi-phase series capacitor DC-DC converter and the control method thereof provided by the present disclosure can release the phase interleaving clock of at least two-phase structure, eliminate the delay time of phase interleaving, and utilize at least two-phase inductance when the load transiently jumps. At the same time, the load is charged, and the rising slope of the inductor current is at least doubled, which greatly improves the load transient response speed.

Description of drawings

For a more complete understanding of the present disclosure and its advantages, reference will now be made to the following description taken in conjunction with the accompanying drawings, in which:

FIG. 1 schematically shows a circuit diagram of a conventional two-phase series capacitor DC-DC converter;

FIG. 2 schematically shows a load transient jump response curve diagram of a conventional two-phase series capacitor DC-DC converter;

FIG. 3 schematically shows a schematic circuit diagram of a multi-phase series capacitor DC-DC converter provided by an embodiment of the present disclosure;

FIG. 4 schematically shows a working schematic diagram of the power stage circuit provided by the embodiment of the present disclosure when the load is transiently jumped;

FIG. 5 schematically shows a signal schematic diagram of a multi-phase series capacitor DC-DC converter provided by an embodiment of the present disclosure;

FIG. 6 schematically shows a load transient jump response curve diagram of a multi-phase series capacitor DC-DC converter provided by an embodiment of the present disclosure;

FIG. 7 schematically shows a schematic topology diagram of a power stage circuit of a multi-phase series capacitor DC-DC converter provided by an embodiment of the present disclosure;

FIG. 8 schematically shows a flowchart of a control method for a multi-phase series capacitor DC-DC converter provided by an embodiment of the present disclosure.

Detailed ways

Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. It should be understood, however, that these descriptions are exemplary only, and are not intended to limit the scope of the present disclosure. In the following detailed description, for convenience of explanation, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present disclosure. It will be apparent, however, that one or more embodiments may be practiced without these specific details. Also, in the following description, descriptions of well-known structures and techniques are omitted to avoid unnecessarily obscuring the concepts of the present disclosure.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the present disclosure. The terms "comprising", "comprising" and the like as used herein indicate the presence of stated features, steps, operations and/or components, but do not preclude the presence or addition of one or more other features, steps, operations or components.

All terms (including technical and scientific terms) used herein have the meaning as commonly understood by one of ordinary skill in the art, unless otherwise defined. It should be noted that terms used herein should be construed to have meanings consistent with the context of the present specification and should not be construed in an idealized or overly rigid manner.

For a conventional Buck DC-DC converter, the inductor current slope m and ripple Δi _L can be expressed as:

m=(V _in -V _out )/L (1)

Δi _L = m×DT (2)

V _in is the input voltage of the converter, V _out is the output voltage of the converter, L is the inductance value, D is the duty cycle of the power tube control signal, D=V _out /V _in , D<1, T is the switch of the converter cycle, DT represents the conduction time of the power tube per cycle. From equation (1), the inductor current slope is inversely proportional to the inductor value. The inductor current slope represents the current capability of the inductor to charge the load when the load transiently jumps. The greater the slope, the greater the charging current to the load, the faster the recovery speed of the output voltage, the smaller the voltage drop, and the faster the load transient response. high. According to formula (2), when the load transient jumps, the larger the duty cycle D, the longer the charging time DT of the load capacitor in a single cycle, the faster the recovery speed of the output voltage, and the higher the load transient response speed.

FIG. 1 schematically shows a schematic circuit diagram of a conventional two-phase series capacitor DC-DC converter provided by an embodiment of the present disclosure.

As shown in Figure 1, for a two-phase series capacitor DC-DC converter, the most direct way to improve the load transient response speed is to increase the switching frequency of the converter. A small filter inductance value increases the rising slope of the inductor current.

As shown in Figure 1, for a traditional two-phase series capacitor DC-DC converter, _La , _Lb , and C are filter inductors and capacitors, BH, BL, AH, and AL are power switches, and switch nodes SW1, SW2, and SW3 The equivalent parasitic capacitances are C _oss1 , C _oss2 and C _oss3 , respectively. In the application environment of large conversion ratio, the power supply voltage is higher, and the power switch often adopts LDMOSFET (Laterally-Diffused Metal-Oxide Semiconductor Field Effect Transistor, Laterally Diffused Metal-Oxide Semiconductor Field Effect Transistor), resulting in switching nodes SW1, SW2 and SW3 The parasitic capacitances C _oss1 , C _oss2 and C _{oss3 are} larger. When the BH and BL, AH and AL switches are switched, the charges on the capacitors C _oss1 , C _oss2 and C _oss3 are discharged and wasted, and the energy loss can reach C _oss1 V _in ² f _s +C _oss2 V _in ² f _s + C _oss3 V _in ² f _s , so higher switching frequency brings greater switching loss, seriously reducing the energy conversion efficiency.

FIG. 2 schematically shows a load transient jump response curve diagram of a conventional two-phase series capacitor DC-DC converter provided by an embodiment of the present disclosure.

As shown in Figure 2, for a two-phase series capacitor DC-DC converter, due to the inherent 180° phase difference of the two-phase structure, the two-phase inductors cannot charge the load at the same time, so there is room for optimization of the load transient response speed.

The embodiments of the present disclosure provide a DC-DC converter with fast load transient response, which can achieve fast load transient response without increasing the switching frequency, the circuit is simple, and the cost is reduced; at the same time, the circuit can be applied to many It is scalable in the phase-series capacitor DC-DC converter topology.

FIG. 3 schematically shows a schematic circuit diagram of a multi-phase series capacitor DC-DC converter provided by an embodiment of the present disclosure.

It should be noted that the present disclosure provides a multi-phase series capacitor DC-DC converter. For convenience of description, FIG. 3 only shows a two-phase multi-phase series capacitor DC-DC converter.

As shown in FIG. 3 , the DC-DC converter includes two parts, a power stage circuit 210 and a load transient response circuit 220 .

The power stage circuit 210 is used to convert the input DC voltage into a stable output DC voltage with ripples, wherein the power stage circuit 210 includes at least two phase inductors, and there is a preset phase difference between the inductor currents of each phase , used to charge the load alternately in turn. For example, when the power stage circuit 210 only includes two-phase inductors, the phase difference between the inductor currents of each phase is 180°, and when the power stage circuit 210 includes three-phase inductors, each The phase difference between the phase inductor currents is 120°. A two-way switch S _tran is arranged between each adjacent two-phase inductance. When the two-way switch S _tran is turned on, it is connected in parallel with the two-phase inductances connected to the turned-on two-way switch S _tran , and the corresponding two-phase switch S tran is connected in parallel. The inductor simultaneously charges the load.

The load transient response circuit 220 is configured to control at least one of the bidirectional switches S _tran to be turned on when a load transient forward jump occurs, so that at least two-phase inductors charge the load at the same time, so as to quickly respond to the load transient changes.

As shown in FIG. 3 , the power stage circuit 210 is composed of four power switches AH, AL, BH and BL, a flying capacitor CF and two filter inductors _{L a} and L _b . In particular, the circuit also includes a bidirectional switch S _tran connected in parallel between the two switch nodes SW1 and SW2. The bidirectional switch S _trah can be connected together in a manner that the source terminals of two N-type LDMOSFETs are connected together. When its gate-source voltage is at a high level, both switches are turned on, and both switches are in an on state; when its gate-source voltage is at a low level, both switches are turned off, and there is at least one N-type LDMOSFET body. The diode is in reverse bias, which can ensure that the bidirectional switch _Stran is in an off state, and the switching type of the bidirectional switch _Stran is not limited here.

Specifically, the sub-circuit where the inductor of at least one phase of the power stage circuit is located includes: a power switch AH, a power switch AL and a filter inductor L _b , which are connected in sequence; the sub-circuit where the inductor of another at least one phase adjacent to the inductor is located includes: The power switch BH, the capacitor _CF , the power switch BL and _a filter inductor La are connected in sequence; wherein, the input ends of the power switch AH and the capacitor _CF are both connected to the power switch BH, and the power switches BH and AH are respectively Used to control the voltage input of the corresponding sub-circuit; the output terminals of the filter inductor L _b and the filter inductor L _a are connected to the output port of the power stage circuit; the filter inductor L _b and the filter inductor L _a The bidirectional switch S _tran is arranged between the input ports of the power stage circuit; a grounded filter capacitor C is also arranged at the output port of the power stage circuit.

The bidirectional switch S _tran is used to short-circuit the two-phase switch nodes when the load transiently jumps, release the two-phase interleaved clock, and use the two-phase inductor current to charge the load synchronously. The specific load transient jump response curve is shown in Figure 6 shown.

As shown in FIG. 3 , the load transient response circuit 220 includes: an error amplifier 221 , an on-time generation circuit 222 , a transient detection circuit 223 , a transient enhancement logic circuit 224 , and a drive circuit 225 .

The error amplifier 221 is used to calculate the error between the output voltage V _FB of the power stage circuit and the reference voltage V _REF to obtain the error signal V _EA .

The conduction time generating circuit 222 is used for generating control signals of the high-side power transistors of the circuits where the inductors of each phase are located according to the error signal V _EA , and each of the control signals is used to control the circuits where the inductors of each phase are located to be turned on, so as to make The inductors of each phase alternately charge the load in turn.

The transient detection circuit 223 is configured to determine whether the load has a transient forward jump according to the error signal V _EA . Specifically, when the error signal V _EA is greater than the preset signal _VL , it is determined that the load has a transient forward jump. Among them, when it is judged that the load has a transient forward jump, the output transient detection signal Tran_Detected is a high level, otherwise the output is a low level. When the transient detection signal is high, the built-in monostable circuit is triggered to ensure that the signal cannot be triggered again within the rated time.

The transient enhancement logic circuit 224 is configured to generate a control signal for controlling the conduction of the bidirectional switch when a transient forward jump of the detected load occurs.

The driving circuit 225 is configured to control at least one of the bidirectional switches to be turned on according to the control signal.

After a load transient forward jump occurs, the drive circuit 225 is further configured to connect the power switch BL and the power switch AH on the two-phase sub-circuit connected to the turned on at least one bidirectional switch S _tran , the power switch AL is turned off, and the power switch BH is driven to generate a voltage input pulse in response to the load transient forward jump.

When the load transient forward jump does not occur, the driving circuit 225 is further configured to control the on and off of the power switches provided on the circuits where the inductors of each phase are located according to the control signals of the power tubes of the circuits where the inductors of each phase are located On, that is, to control the on-time of the power switch on the circuit where each inductance is located, so that the inductance of each phase alternately charges the load.

In the embodiment of the present disclosure, it is ensured that when a transient forward jump of the load is detected, the power transistor BL of the first phase and the power transistors AH and AL of the second phase are turned off, so as to generate a _Stran control that releases the two-phase interleaved clock. Signal.

In addition, the driving circuit 225 is also used to control the power switch provided on the circuit where the inductance of each phase is located when the load transient forward jump does not occur, so that the inductance of each phase alternately conducts the load on the load. Charge.

FIG. 4 schematically shows the working schematic diagram of the power stage circuit provided by the embodiment of the present disclosure when the load transient jumps response; FIG. 5 schematically shows the multi-phase series capacitor DC-DC converter provided by the embodiment of the present disclosure. The signal schematic diagram of ; FIG. 6 schematically shows the load transient jump response curve diagram of the multi-phase series capacitor DC-DC converter provided by the embodiment of the present disclosure.

Referring to Figure 4, Figure 5, and Figure 6, the gray part in Figure 4 represents the power tube is turned off, BH, BL, AH, and AL in Figure 5 correspond to the gate terminal control signals of the corresponding power tube in Figure 6, and S _tran represents the bidirectional switch S The control signal of _tran , when the transient detection signal Tran_Detected is high, the control signal SBH of the first phase power tube BH and the control signal Tran_EN of the bidirectional switch S _tran are high, and the control signal SAH of the second phase is low. level, the gate terminal control signal of each phase power tube and the gate terminal control signal of the bidirectional switch S _tran based on the Tran_EN signal are obtained respectively through the driving circuit, the power tubes AH, AL and BL are turned off, and the power tubes BH and the two-phase switch S _tran are turned on. . Referring to Figure 6, the bidirectional switch S _tran is turned on, and the two-phase inductance is used to charge the load at the same time, eliminating the delay caused by the existing two-phase interleaved clock, and speeding up the load transient response speed. Referring to Figure 5, the first-phase power transistor BH prolongs the on-time in response to the control signal SBH to provide corresponding energy to the load in response to the transient change of the load.

In the embodiment of the present disclosure, during the transient forward jump period, the two-phase inductors can simultaneously charge the load capacitance, which is equivalent to two-phase inductors being connected in parallel, and the inductor current rising slope is formula (3):

Among them, D is the duty cycle of the power tube BH in steady state.

In the traditional two-phase series capacitor DC-DC converter, during the transient forward jump of the load, the rising slope of the inductor current is equation (4):

It can be seen from equations (3) and (4) that the multi-phase series capacitor DC-DC converter provided by the present disclosure releases the two-phase interleaved clock when the load has a transient forward jump, and uses the two-phase inductance to charge the load at the same time. The inductor current rising slope is doubled for fast load transient response. Correspondingly, when the converter is an N-phase series capacitive DC-DC converter, when a transient jump occurs in the load, the N-phase inductor can be used to charge the load at the same time, so that the rising slope of the inductor current is increased by N times, and it has a fast load. Transient response capability, wide application range and scalability.

FIG. 7 schematically shows a schematic diagram of a topology structure of a power stage circuit provided by an embodiment of the present disclosure.

As shown in FIG. 7 , the embodiments of the present disclosure also provide various topology structures of the power stage circuit, wherein (1) a multi-phase series capacitor topology is shown, and (2) a series capacitor topology is schematically shown Capacitor+3-level hybrid topology, (3) schematically shows a simplified version of a polyphase series capacitor topology, (4) schematically shows a dual-inductor hybrid Dickson topology. The topological structure of the power stage circuit provided in this embodiment is not limited to the structures shown in FIG. 7 , but all of them can realize the simultaneous charging of the multi-phase inductance to the load by closing the bidirectional switch to quickly respond to the transient change of the load.

The topology of the multi-phase series capacitor DC-DC converter provided by the present disclosure can be a step-up or step-down multi-phase series capacitor power stage circuit. When the power stage circuit is the step-up circuit shown in FIG. 7 (5) The multi-phase series capacitor topology structure, the multi-phase series capacitor DC-DC converter provided by the present disclosure has a transient negative jump in the load, the multi-phase interleaved clock is released, and the multi-phase inductor is used to discharge the load at the same time, and the slope of the inductor current decreases. Double the size, with fast load transient response capability.

FIG. 8 schematically shows a flowchart of a control method for a multi-phase series capacitor DC-DC converter provided by an embodiment of the present disclosure.

As shown in FIG. 8 , the control method includes S810.

S810, when a transient forward jump occurs in the detected load, control the bidirectional switch between at least two adjacent inductors in the power stage circuit to be turned on, so that the at least two adjacent inductors simultaneously perform the load on the load. charge to quickly respond to transient changes in the load.

In an embodiment of the present disclosure, in response to a transient forward jump of the load, at least one bidirectional switch in the power circuit of the converter shown in FIG. 3 may be controlled to be closed, so that at least two-phase inductors are simultaneously charged to the load, so as to at least Double the corresponding speed.

Specifically, in S810, when the transient forward jump of the detected load occurs, the method further includes:

S811: Turn off the power switch BL, the power switch AH, and the power switch AL on the two-phase sub-circuit connected to at least one of the turned-on bidirectional switches in the power stage circuit, and drive the power switch BH to respond to a load transient Positive transition voltage input pulse.

In S810, when it is detected that a transient forward jump occurs in the load, controlling the conduction of the bidirectional switches between at least two adjacent inductors in the power stage circuit specifically includes S812-S815.

S812, calculate the error between the output voltage of the power stage circuit and the reference voltage to obtain an error signal.

S813, according to the error signal, determine whether a transient forward jump occurs in the load.

When the error signal exceeds the rated amplitude VL, it is judged that the load current has a transient forward jump, and the output transient detection signal Tran_Detected is high level. If the error signal does not exceed the rated amplitude VL, it is judged that the load current has no transient forward transition. Transition, the output transient detection signal Tran_Detected is low level.

S814, when it is detected that a transient forward jump occurs in the load, a control signal for controlling the conduction of the bidirectional switch is generated.

S815, control at least one of the bidirectional switches to be turned on according to the control signal.

When the transient detection signal Tran_Detected is at a high level, the power transistor BL of the first phase and the two power transistors AH and AL of the second phase are turned off, the bidirectional switch S _tran is triggered to conduct, and the two-phase inductor current is used to charge the load at the same time. Achieve transient enhancement effects.

The method also includes the S820:

S820, when the load is working normally, control the bidirectional switch to turn off, and control the inductors of each phase to charge the load alternately in turn.

Among them, when the load has a transient forward jump and returns to normal, the drive circuit 225 will control the bidirectional switch to turn off, and the power switch BL, power switch BH, power switch AH, and power switch AL are controlled by the two-phase control signals SBH and SAH. The control is turned on in sequence, the phase difference of the inductor currents of each phase is restored, and the load is alternately charged in sequence.

Those skilled in the art will appreciate that various combinations and/or combinations of features recited in various embodiments and/or claims of the present disclosure are possible, even if such combinations or combinations are not expressly recited in the present disclosure. In particular, various combinations and/or combinations of the features recited in the various embodiments of the present disclosure and/or in the claims may be made without departing from the spirit and teachings of the present disclosure. All such combinations and/or combinations fall within the scope of this disclosure.

Although the present disclosure has been shown and described with reference to specific exemplary embodiments of the present disclosure, those skilled in the art will appreciate that, without departing from the spirit and scope of the present disclosure as defined by the appended claims and their equivalents, Various changes in form and detail have been made in the present disclosure. Therefore, the scope of the present disclosure should not be limited to the above-described embodiments, but should be determined not only by the appended claims, but also by their equivalents.

Claims (10)

1. A multiphase series capacitor dc-dc converter, comprising:

the power stage circuit is used for converting input direct-current voltage into stable direct-current voltage required by a load, and comprises at least two phase inductors, phase difference of preset intervals exists between currents of the two phase inductors and is used for charging the load in sequence and alternately, a two-way switch is arranged between every two adjacent phase inductors, and when the two-way switches are conducted, the corresponding two phase inductors simultaneously charge the load;

and the load transient response circuit is used for controlling at least one bidirectional switch to be conducted when the forward jump of the load transient occurs, so that at least two phases of inductors charge the load at the same time, and the transient change of the load is responded quickly.

2. The converter of claim 1, wherein the load transient response circuit comprises:

the error amplifier is used for calculating the error between the output voltage of the power level circuit and the reference voltage to obtain an error signal;

the transient detection circuit is used for judging whether the load generates transient forward jump according to the error signal;

the transient enhancement logic circuit is used for generating a control signal for controlling the conduction of the bidirectional switch when the transient forward jump of the load is detected;

and the driving circuit is used for controlling the conduction of at least one bidirectional switch according to the control signal.

3. The converter according to claim 2, wherein when a load transient forward transition occurs, at least one of said bidirectional switches is turned on, and then two of said inductors connected to said turned on bidirectional switches are connected in parallel.

4. The converter of claim 2, wherein the load transient response circuit further comprises:

the conduction time generating circuit is used for generating control signals of a power tube of a circuit where each phase of inductor is located according to the error signals, and each control signal is respectively used for controlling the circuit where each phase of inductor is located to be conducted so as to enable each phase of inductor to charge the load in sequence and alternately;

and the driving circuit is also used for controlling the on-off of a power switch arranged on a circuit where the inductor of each phase is positioned according to the control signal of each phase when the transient forward jump of the load does not occur, so that the inductors of each phase charge the load in turn and alternately.

5. The converter according to claim 2, wherein the sub-circuit of the power stage circuit in which at least one phase of inductance is located comprises:

power switch AH, power switch AL and filter inductor L_bSequentially connecting;

the sub-circuit where the other at least one phase of inductor adjacent to the inductor is located comprises:

power switch BH, capacitor C_FPower switch BL and filter inductor L_aSequentially connecting;

wherein the power switch AH and the capacitor C_FThe input ends of the power switches BH and AH are respectively used for controlling the voltage input of the corresponding sub-circuits; the filter inductor L_bAnd a filter inductance L_aThe output ends of the power stage circuits are connected with the output port of the power stage circuit; the filter inductor L_bAnd a filter inductor L_aThe bidirectional switch is arranged between the input ports; and the output port of the power level circuit is also provided with a grounded filter capacitor C.

6. The converter of claim 5, wherein the driving circuit is further configured to turn off the power switch BL, the power switch AH, and the power switch AL in the two-phase sub-circuit connected to the conducting at least one bidirectional switch after the load transient forward transition occurs, and to drive the power switch BH to generate a voltage input pulse in response to the load transient forward transition.

7. The multiphase series capacitor dc-dc converter control method applied to the multiphase series capacitor dc-dc converter according to any one of claims 1 to 6, comprising:

when the transient forward jump of the load is detected, the bidirectional switch between at least two adjacent inductors in the power level circuit is controlled to be conducted, so that the at least two adjacent inductors charge the load at the same time, and the transient change of the load is quickly responded.

8. The control method according to claim 7, characterized by further comprising:

when the load works normally, the bidirectional switch is controlled to be switched off, and the inductors of all phases are controlled to charge the load in sequence and alternately.

9. The control method of claim 8, wherein when detecting a transient forward jump in the load, further comprising:

and turning off a power switch BL, a power switch AH and a power switch AL on a two-phase sub-circuit connected with the conducted at least one bidirectional switch in the power level circuit, and driving a power switch BH to generate a voltage input pulse responding to the transient forward jump of the load.

10. The method of claim 7, wherein controlling the bidirectional switch between at least two adjacent inductors of the power stage circuit to conduct when detecting a transient forward jump of the load comprises:

calculating an error between the output voltage of the power level circuit and a reference voltage to obtain an error signal;

judging whether the load generates transient forward jump according to the error signal;

when the transient forward jump of the load is detected, a control signal for controlling the conduction of the bidirectional switch is generated;

and controlling at least one bidirectional switch to be conducted according to the control signal.

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