A thermal balancing phase management system for a multiphase interleaved buck converter

Abstract

The application discloses a kind of thermal equilibrium phase management systems of multiphase staggered buck converter, it is related to power electronics field.The system includes working phase quantization module, temperature monitoring module, closed-loop control module and fault early warning module, by real-time monitoring to each phase inductance current and switch tube temperature, the number of effective working phase is dynamically adjusted, phase working enable signal is generated, and PWM signal modulation is realized in cooperation with closed-loop control.The system can be according to load current and temperature change, select the phase with lower temperature to run, realize inter-phase thermal balance, improve system reliability and device service life.Compared with prior art dynamic phase management technology, the application can effectively optimize inter-phase heat distribution, reduce switch tube aging, improve system efficiency and long-term stability.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power electronics, and particularly relates to a thermal balance phase management system of a multi-phase interleaved Buck converter. BACKGROUND

[0002] With the increasing demand for high power and high energy efficiency power supply of electronic devices, the multi-phase interleaved Buck converter, as a common microprocessor power management solution, is widely used. Since the microprocessor load is usually dynamically switched between light load and heavy load, in the heavy load stage, all phases need to be put into work to realize the sharing of large current among phases in order to reduce the current stress of a single device and improve the overall conversion efficiency. However, in the light load stage, if all phases are still working, the system conversion efficiency will be reduced due to the increase of no-load loss, so the number of effective working phases needs to be reduced to improve the light load efficiency through dynamic phase management.

[0003] The existing dynamic phase management technology usually adopts a "phase rotation switching" scheme, that is, after determining the number of working phases, the load current is distributed to each phase in turn to realize dynamic phase management. However, this scheme has the following disadvantages: first, even if the same type of switch tube device is used, there are still parameter deviations such as parasitic resistance and turn-on loss, and these slight differences will be intensified in long-term operation, which will cause the working temperature distribution of different phase switch tubes to be unbalanced. Secondly, due to the poor heat dissipation conditions caused by PCB layout, the switch tubes of different phases will also have uneven heat distribution in actual application, and long-term thermal mismatch will reduce the reliability of the device, shorten the service life, and even cause local phase devices to fail due to overheating.

[0004] Therefore, the existing dynamic phase management technology cannot effectively solve the system reliability problem caused by device thermal imbalance. SUMMARY

[0005] In order to overcome the problem of system reliability reduction caused by switch tube temperature distribution imbalance in the prior art multi-phase interleaved Buck converter, the present application provides a thermal balance phase management system of a multi-phase interleaved Buck converter, which realizes dynamic phase management and fault diagnosis based on temperature balancing.

[0006] To achieve the above object, the present application provides the following technical scheme:

[0007] The thermal balance phase management system of the multi-phase interleaved Buck converter of the present application includes a working phase quantization module, a temperature monitoring module, a closed-loop control module and a fault warning module, each module realizes thermal balance management, dynamic control and fault warning of the multi-phase system through signal interaction, and the functions and signal flow are as follows:

[0008] The working phase quantization module is configured to sample output voltages and phase inductance currents of the multi-phase interleaved Buck converter, monitor current sharing states among phases, generate current sharing state signals, and determine a current effective working phase number by comparing a load current with a preset phase current threshold value.

[0009] The temperature monitoring module is configured to monitor temperature conditions of phase switch tubes, generate temperature diagnosis signals including single tube temperature abnormality, temperature imbalance within a phase, temperature imbalance among phases, and the like by comprehensively judging a switch tube temperature value and safety intervals, temperature rise ratios, and the like, and output phase working enable signals according to matching relationships between temperature and load, to realize dynamic temperature balance management of phases.

[0010] The closed loop control module is configured to generate duty cycle modulation signals by sequentially passing through a current sharing loop, a voltage loop and a current loop based on inductance currents, output voltages and reference voltage signals, compare the duty cycle modulation signals with phase-shifted carrier signals to generate initial PWM driving signals P k , and finally output final upper tube PWM driving signals P 2k-1 and lower tube PWM driving signals P 2k by performing logical AND operation with phase working enable signals.

[0011] The fault early warning module is configured to receive various diagnosis signals from the working phase quantization module and the temperature monitoring module, judge whether there are current imbalance, temperature abnormality or thermal distribution imbalance and the like, and output corresponding early warning signals when detecting abnormalities.

[0012] Compared with the prior art, the present application has the following beneficial effects:

[0013] The present application realizes heat balance distribution of the multi-phase Buck converter by combining load current monitoring and temperature distribution among phases, using a temperature monitoring module to monitor temperature conditions of phase switch tubes in real time, dynamically selecting phases with relatively low temperatures to operate, avoiding some phases from being in high temperature working state for a long time due to device parameter changes or poor heat dissipation conditions, effectively reducing aging rates of devices caused by thermal mismatch, and improving system reliability and device service life.

[0014] The present application integrates a fault early warning module, which can diagnose current imbalance among phases, switch tube temperature abnormality, thermal mismatch and the like in real time, output early warning signals or shut down abnormal phases in time, and significantly improve system safety and maintainability. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a technical roadmap of a dynamic heat balance phase management system of a multi-phase parallel Buck converter provided by the present application.

[0016] Figure 2 is a logic diagram of a temperature monitoring module in a dynamic thermal balance phase management system of a multiphase parallel Buck converter provided by the present application.

[0017] Figure 3 is a logic diagram of a closed-loop control module in a dynamic thermal balance phase management system of a multiphase parallel Buck converter provided by the present application.

[0018] Figure 4 is a phase operation timing diagram of a conventional phase rotation switching three-phase parallel Buck converter.

[0019] Figure 5 is a phase operation timing diagram of a three-phase parallel Buck converter of a dynamic thermal balance phase management system provided by the present application. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. It should be understood that the embodiments are only used to illustrate the present application, and do not limit the protection scope of the present application. Unless specifically stated, the processes, control strategies and parameter settings involved in the implementation of the present application are all known in the art or can be determined by the skilled person.

[0021] Figure 1 The overall structure of the thermal balance phase management system of the multiphase interleaved Buck converter of the present application is shown. The system mainly includes a working phase quantization module 100, a temperature monitoring module 200, a closed-loop control module 300 and a fault warning module 400, and each module cooperates to realize temperature-based phase management.

[0022] The functions of each module and the signal interaction relationship are as shown in Figure 1 .

[0023] Referring to Figure 1 , the working phase quantization module 100 is used to collect the output voltage and the inductor current of each phase of the multiphase interleaved Buck converter, to perform current sharing monitoring based on the inductor current sampling results, to generate a current sharing state signal sign1 and input it to the fault warning module; at the same time, by comparing the load current with a preset threshold, the number of current effective working phases m is determined, and the m value is input to the temperature monitoring module 200 to guide the subsequent phase temperature monitoring and enable control.

[0024] The temperature monitoring module 200 consists of a temperature acquisition unit, a temperature monitoring unit, and a phase control unit. The temperature acquisition unit collects the temperature signals of each phase switch in real time using temperature sensors and compares them with preset safe temperature ranges to determine whether each switch is within its normal operating temperature range, generating a switch temperature anomaly signal sign2. The temperature monitoring unit analyzes the temperature rise of the upper and lower tubes within the same phase, calculates the ratio K of the temperature rise of the upper and lower tubes within the same phase, and generates a phase thermal imbalance signal sign3. Simultaneously, based on the interphase temperature distribution, it outputs an interphase thermal imbalance signal sign4. The phase control unit receives the number of effective working phases m from the working phase quantization module, and based on the monitored average temperature of each phase, dynamically selects m phases with relatively low temperatures, generating phase enabling signals F1 to F2. N The data is transmitted to the closed-loop control module 300 to achieve dynamic activation or shutdown control of each phase.

[0025] The closed-loop control module 300 is responsible for the closed-loop control of the multiphase converter. After receiving the voltage and inductor current from the working phase module 100, the closed-loop control module 300 generates the initial PWM drive signal P' for each phase through the coordinated action of the current sharing loop, voltage loop, and current loop. k Then, by combining the phase enable signal input from the temperature monitoring module with a logical AND operation, the final PWM drive signal is output to the corresponding switches of the interleaved parallel Buck converter to realize the on / off control of each switch.

[0026] The fault early warning module 400 is responsible for processing and issuing early warnings of system fault information. The fault early warning module 400 receives the current sharing status signal sign1 output by the working phase quantization module. If the current distribution is uneven, an early warning is issued. The fault early warning module also receives the switching transistor temperature abnormality signal sign2, the intra-phase thermal imbalance signal sign3, and the inter-phase thermal imbalance signal sign4 output by the temperature monitoring module. If a fault or temperature abnormality is detected, it can promptly disconnect the phase or issue an early warning signal to ensure system safety.

[0027] To further clarify the operating mechanism of the working phase quantization module 100, its specific process is described in detail below:

[0028] Data Acquisition and Input Processing: The data sampling unit acquires the converter output voltage V through a voltage sensor. o And the inductor current I of each phase is collected by a current sensor. k The sampling signal is synchronously input to the digital processing chip, and the sampling frequency is f.

[0029] Current sharing monitoring and status assessment: The current sharing monitoring unit is based on the sampled inductor current I. k Find the average value I of the N-phase inductor current.av = (I1+I2+…+I k ) / N. When |I av -I k When |<ε (ε is the allowable current sharing error), output current sharing status signal sign1. k =0; otherwise, output sign1 k =1, used to indicate phase imbalance.

[0030] Load current calculation and phase decision: The phase decision unit calculates the load current I. sum =I1+I2+…+I N And sequentially compare it with the preset phase current threshold I. th1 to I thN The comparisons are made, and the system power ranges are divided, specifically as follows:

[0031] When I sum ≤I th1 Within the first power range, the effective number of working phases is determined to be m = 1; when I th1 sum ≤I th2 In the second power range, the effective number of working phases is determined to be m = 2; and so on; when I sum >I th(N-1) Within the Nth power range, the effective number of operating phases is determined to be m = N. The preset current threshold I... th1 To I th(N-1) Specific parameters set according to the experimental or system operating characteristics

[0032] Finally, the phase decision unit outputs the number of effective working phases m to the temperature monitoring module 200 as the basis for subsequent phase selection and enable control.

[0033] The temperature monitoring module 200 is responsible for monitoring the temperature status of each phase switch in real time and executing corresponding control strategies based on the monitoring results. The following is combined with... Figure 2 Describe its specific workflow in detail:

[0034] The temperature acquisition unit acquires the temperature of the k-th phase switch transistor through a temperature sensor, and records it as: k-th phase upper transistor temperature T 2k-1 and the temperature T of the lower tube of phase k 2k The sampled data is quantized at the sampling frequency f and converted into a digital signal. See [link / reference] Figure 2 The acquired temperature signal T first passes through a window comparison module, which sets its upper and lower limits to T. max T min T max T is the highest junction temperature allowed by the internal silicon chip of the switching transistor. min ​T0 is the temperature of the switch tube at room temperature when the switch tube is not working. The temperature of the switch tube exceeds T max , which brings thermal runaway or permanent damage, and the temperature is lower than T min . There may be a condition of temperature sensor failure. If the temperature T 2k-1 / 2k of any switch tube exceeds T max , and T 2k-1 / 2k < T min , the corresponding switch tube temperature abnormal signal sign2 2k-1 / 2k = 1 is input to the fault warning module 400, the fault warning module 400 sends a warning signal, and W k = 0 is output, and the linkage closed-loop control module closes the PWM drive signal of the kth phase.

[0035] Then the collected temperature T 2k-1 of the upper tube and the temperature T 2k of the lower tube of the kth phase are input to the arithmetic logic unit ALU, and the temperature rises of the two tubes are calculated respectively, ΔT 2k-1 = T 2k-1 -T0, and ΔT 2k = T 2k -T0, T0 is the ambient temperature, then the ratio K of the temperature rises of the upper and lower switch tubes of the kth phase = ΔT 2k-1 / ΔT 2k , if the ratio K of the temperature rises of the upper and lower tubes of the same phase of the kth phase exceeds the preset range [K min , K max ], the intra-phase thermal imbalance signal sign3 k = 1 is generated, and if the ratio K of the temperature rises of the upper and lower tubes of the same phase of the kth phase does not exceed the preset range [K min , K max ], the intra-phase thermal imbalance signal sign3 k = 0 is generated. The preset range [K min , K max ] should be set in combination with the safe working area parameters of the two switch tubes, which can be determined by a person skilled in the art according to the device characteristics and actual working conditions. When K≥K max , the temperature rise of the upper tube of the phase is greater than that of the lower tube, indicating that the upper tube works in a heavy load state for a long time, and the other tube works in a light load state, which will lead to system instability. According to the parameter K, the specific parameters of the two switch tubes in the appropriate phase can be selected to reduce such imbalance.

[0036] The collected temperature T 2k-1 of the upper tube and the temperature T 2k of the lower tube of the same phase are averaged to obtain the phase average temperature T avk = (T 2k-1 + T 2k ) / 2 of the kth phase. The phase average temperature T avkand the number of active phases m are input into a logical operation unit, which first calculates the average value T av = (T av1 + T av2 + … + T avN ) / N of the N-phase average temperatures, and then calculates the difference between each phase average temperature T avk and the average value. If |T av -T avk | < ε T (ε T is the maximum value of the phase average temperature deviation from the average temperature allowed by the thermal equilibrium multi-phase parallel Buck converter), the phase thermal balancing effect is good, the inter-phase thermal imbalance signal sign4 k of the phase is 0, otherwise the phase thermal imbalance and the inter-phase thermal imbalance signal sign4 k of the phase is 1. The N-phase average temperatures are sorted, and the m-th largest temperature T m is output. T m is input into a comparator for comparison with each phase average temperature T avk . If T avk > T m , the k-th phase active enable signal F k is output as 0; if T avk ≤ T m , the k-th phase active enable signal F k is output as 1. The phase enable signals F1 to F N are output to the closed-loop control module 300 for phase dynamic control.

[0037] The working process of the closed-loop control module 300 is as follows, and the specific process is shown in Figure 3 :

[0038] Current sharing loop: the inductor currents I1, I2, …, I N are input into the current sharing loop, and the average value I av = (I1+I2+…+I N ) / N of the N-phase inductor currents is calculated. I av is input into the subsequent current sharing loop as a current sharing reference. The inductor current I k of each phase is compared with the calculated average value I av of the N-phase inductor currents, and the current sharing error signal e Ik = I av -I k is obtained, where e Ik represents the current sharing error signal of the k-th phase. The error signal is used for closed-loop control to adjust the current distribution of each phase, so that all phases tend to be balanced.

[0039] Voltage loop: the output voltage Vo and given reference voltage V Ref The original given reference voltage V o With the phase current sharing error signal e Ik The two voltages are summed to output a corrected reference voltage V'. Refk =V Ref +e Ik The output voltage V o With the corrected phase reference voltage V' Refk By comparison, the voltage error signal e is obtained. Vk =V' Refk -V o This signal is used to maintain the output voltage at the desired level.

[0040] Current loop: This will reduce the voltage error e Vk The input is fed into the corresponding proportional-integral (PI) control unit, which outputs a current reference quantity I. Refk The system first uses the reference current I. Refk With the inductor current I of each phase k By performing subtraction, the current error signal e for each phase is obtained. Ik =I Refk -I k The error signal e Ik The signal is then input to the proportional-integral control unit, which outputs the modulation signal V for the k-th phase. rk V rk ∈[0, 1]. Its purpose is to allow the proportional-integral (PI) control unit to continuously adjust the PWM drive signal of the corresponding phase, so that the actual inductor current I... k Tracking reference current I Refk This enables precise current control and current sharing.

[0041] PWM drive signal modulation unit: After determining the total number of currently operating phases m, the phases actually put into operation are renumbered sequentially. The sequence number of the k-th phase (original number) in the effective phases is denoted as k'. The initial sawtooth carrier of the k-th phase (f of the sawtooth carrier) is... c The switching frequency of the switching transistor (with the highest value of the sawtooth carrier being 1 and the lowest value being 0) is used for phase shifting. The shift angle of the sawtooth carrier in the effective operating phase is 360°(k'-1) / m, where k' = 1, 2, ..., m. Then, the phase-shifted sawtooth carrier V... ck With modulation signal V rk Comparison:

[0042]

[0043] This generates the initial PWM drive signal P' for the k-th phase. kThis phase-shifting method allows for the distribution of the switching timing of each phase in a multiphase interleaved Buck converter.

[0044] Phase enable and final PWM drive signal generation: Obtaining the initial PWM drive signal P' k Then, it is connected to the phase enable signal F. k Perform a logical AND operation to generate the final PWM drive signal: P 2k =P' k ∧F k , When the phase is not allowed to work (F) k =0), the PWM output is turned off, then the PWM drive signal P of the lower phase transistor in phase k is... 2k The PWM drive signal P of the k-phase upper transistor is always low. 2k-1 It remains high. Conversely, the phase is allowed to operate (F). k When =1), the PWM output remains normal, and the PWM drive signal P of the k-phase transistor is... 2k Let the duty cycle be V rk (V rk The value is the PWM drive signal of the duty cycle D), and the PWM drive signal P of the k-phase upper transistor. 2k-1 For a duty cycle of 1-V rk The PWM drive signal. Through the above process, the closed-loop control module realizes dynamic phase management and precise control based on the coordination of voltage, current, current sharing and temperature.

[0045] The working logic of the fault early warning module 400 is as follows:

[0046] The fault warning module 400 receives the current sharing status signal sign1 provided by the working phase quantization module, and the switch tube temperature abnormality signal sign2, the intraphase thermal imbalance signal sign3, and the interphase thermal imbalance signal sign4 provided by the temperature monitoring module.

[0047] When the k-th phase current sharing state signal sign1 k When = 1, it is determined that there is uneven current between phases, and a current sharing warning signal is output, indicating that the current deviation of the k-th phase exceeds the allowable deviation of current sharing.

[0048] When the temperature of the k-th phase switch transistor is abnormal, signal sign2 2k-1 =1 or sign2 2k When = 1, it is determined that there is a temperature abnormality in the k-th phase switch, and a control signal W is immediately generated. k The signal is sent to the closed-loop control module, triggering the phase shutdown and simultaneously outputting a temperature warning signal to indicate abnormal device temperature.

[0049] When the internal thermal imbalance signal of the kth phase is sing3 kWhen =1, it is determined that the temperature rise difference of the kth phase is large, and there is an unbalanced load, and a phase internal thermal imbalance warning signal is output.

[0050] When the kth phase inter-phase thermal imbalance signal sign4 k When =1, it is determined that there is an inter-phase thermal distribution imbalance, and the temperature deviation value of the kth phase exceeds the allowed range, an inter-phase thermal imbalance warning signal is output, reminding the user to check the device and temperature sampling frequency setting.

[0051] To verify the effect of the dynamic thermal balance phase management system of the application, the following shows the advantages of the application compared with the existing dynamic phase management strategy in the application scenario of a typical three-phase interleaved parallel Buck converter.

[0052] In the traditional dynamic phase cycle management strategy, the system adjusts the number of effective working phases according to the load current I sum The number of effective working phases is dynamically adjusted. For example, when I sum is in the medium load interval, the system enables 2 phases to achieve the best conversion efficiency (T s =1 / f s , f s is the phase cycle switching frequency), and the working timing diagram is as shown in Figure 4 However, this scheme does not consider the differences in device parameters and actual heat dissipation conditions caused by PCB layout of each phase switch tube, resulting in significant differences in the temperature of each phase switch tube during long-term operation, making it difficult to achieve thermal balance of the system.

[0053] In contrast, the thermal balance dynamic phase management strategy proposed by the application effectively improves the above shortcomings through real-time temperature monitoring and dynamic phase distribution. As shown in Figure 5 (1) At time 0, the temperature monitoring module detects that the temperature of the third phase switch tube is the highest, the system closes the third phase and only enables the first and second phases to operate, with a duration T=1 / f, f being the temperature sampling frequency; (2) At time T, the temperature of the third phase is still higher than that of the other phases, the system continues to close the third phase and only the first and second phases work; (3) At time 2T, the temperature of the first phase rises to the highest, the system switches to the second and third phases to work and shuts down the first phase; the rest of the phases follow the same rule to perform temperature balance management, and continuously switch to achieve long-term thermal distribution balance.

[0054] By dynamically selecting the phase with relatively low temperature to operate, the application can achieve dynamic balance of inter-phase heat distribution, reduce the risk of long-term high temperature operation of the switch tube, and significantly improve the thermal balance and device reliability of the system.

[0055] The terms "Buck converter", "phase", and the like are commonly used in the field of power electronics and control engineering, and are used to describe the technical solutions herein. The specific meanings should be understood in the context and should not be considered as limiting the structure or function of the system of the present application.

[0056] The terms "receive", "control", "input", and the like should be understood broadly and include direct or indirect, physical or logical, wired or wireless connection and signal transmission. It also includes software and hardware control and processing through intermediate units.

[0057] The "modules" and "units" in the present application are only logical divisions of functions, and are not specific to the physical structure. They can be designed separately or integrated according to needs when implemented.

[0058] The terms "kth phase", "in-phase", "inter-phase", and the like in the present application are only used to distinguish the relative relationship of different phases, modules or elements, and do not have limitations on space, structure or arrangement order. "k=1, 2,..., N" is used to represent any one phase number, and N is the total number of phases.

[0059] Those skilled in the art should know that various equivalent replacements, function adjustments or local improvements of the system structure, signal flow, control strategy or module division in the present application can be made without departing from the core technical solutions of the present application, and all should fall within the protection scope of the present application.

Claims

1. A thermal balancing phase management system for a multiphase interleaved Buck converter, characterized by, The application relates to a multi-phase interleaved Buck converter, which comprises a working phase quantification module, a temperature monitoring module and a closed-loop control module. The working phase quantification module is used for collecting output voltages and phase inductor currents of the multi-phase interleaved Buck converter, judging the current balance among the phases through current equalization monitoring, generating a current equalization state signal, calculating the sum of the phase inductor currents to obtain a load current, comparing the load current with a preset phase current threshold value to determine the number m of current effective working phases, and outputting the number m of current effective working phases. The temperature monitoring module is used to collect the temperature of each phase switch transistor and compare it with a preset normal operating temperature range to generate a switch transistor temperature anomaly signal; it is also used to calculate the temperature rise ratio of the upper and lower switch transistors in the same phase and compare it with a preset range, generating a phase thermal imbalance signal based on the comparison result; further, based on the effective number of operating phases m, it selects the m-th largest phase average temperature value T from the phase average temperatures of each phase. m and the m-th largest phase average temperature value T m The phase operation enable signal is output by comparing the phase average temperature with that of each phase, and a phase thermal imbalance signal is generated. The closed-loop control module is used for receiving the phase inductor currents, a given reference voltage and output voltages, generating an initial PWM driving signal through a current equalization loop, a voltage loop and a current loop, performing logical AND operation on the initial PWM driving signal and the working enable signal of each phase output by the temperature monitoring module, and outputting a final PWM driving signal.

2. A thermal balancing phase management system for a multiphase interleaved Buck converter as claimed in claim 1, wherein, The working phase quantification module compares the load current with a preset load current threshold value, divides the load current into N power intervals, and outputs the number m of effective working phases corresponding to the N power intervals. When the load current is less than or equal to a first threshold value, the number m of effective working phases is determined to be 1, when the load current is greater than the first threshold value and less than or equal to a second threshold value, the number m of effective working phases is determined to be 2, and the number m of effective working phases in the remaining power intervals is sequentially determined in the same way.

3. A thermal balancing phase management system for a multiphase interleaved Buck converter as recited in claim 1, wherein, The temperature monitoring module further comprises a temperature acquisition unit and a phase control unit. The temperature acquisition unit is used for collecting temperature signals of the phase switch tubes, converting the temperature signals into digital signals at a temperature sampling frequency, comparing the temperature value T of each switch tube with a preset normal working temperature interval, and generating a switch tube temperature abnormal signal. The temperature monitoring unit is used for calculating the ratio K of temperature rises of the upper and lower switch tubes in the same phase, comparing K with a preset range [K min , K max ], and generating an in-phase thermal imbalance signal according to the comparison result; The phase control unit is used for calculating the average temperature of the two switch tubes of each phase, i.e. the phase average temperature, selecting the mth largest phase average temperature value among all the phase average temperatures, comparing the mth largest phase average temperature value with each phase average temperature, outputting a phase working enable signal, and generating an inter-phase thermal imbalance signal based on the inter-phase temperature balance.

4. A thermal balancing phase management system for a multiphase interleaved Buck converter as recited in claim 1, wherein, The closed-loop control module further comprises a current equalization control unit, a voltage control unit and a current control unit. The current equalization control unit is used for calculating an average inductor current according to the N-phase inductor currents, comparing the average inductor current with each phase inductor current to generate a phase current equalization error signal. The voltage control unit is used for adding the phase current equalization error signal to a given reference voltage to generate a phase reference voltage, comparing the phase reference voltage with an output voltage to generate a phase voltage error signal, and processing the phase voltage error signal through a proportional integral control unit to generate a target reference current of each phase. The current control unit is used for comparing the target reference current of each phase with the inductor current of the corresponding phase to generate a phase current error signal, and processing the phase current error signal through a proportional integral control unit to generate a phase duty cycle modulation signal. The PWM driving signal modulation unit is configured to compare each phase duty cycle modulation signal with a corresponding phase-shifted carrier signal to generate an initial PWM driving signal for each phase, and to perform a logical AND operation between the initial PWM signal and a corresponding phase operation enable signal to output a final PWM driving signal.

5. The thermal balancing phase management system for multiphase interleaved Buck converter of claim 1, wherein, The system further comprises a fault early warning module, which comprises: a signal receiving unit configured to receive a current sharing state signal generated by the operation phase quantization module, and a switch tube temperature abnormal signal, an intra-phase thermal imbalance signal and an inter-phase thermal imbalance signal generated by the temperature monitoring module; a warning determination unit configured to: determine the current balance of each phase according to the current sharing state signal, and generate a first warning signal if there is an unbalanced current; determine the temperature state of each switch tube according to the switch tube temperature abnormal signal, and generate a second warning signal if any switch tube has an abnormal temperature; determine the load balance of upper and lower tubes in the same phase according to the intra-phase thermal imbalance signal, and generate a third warning signal if the load is unbalanced; determine the inter-phase temperature balance according to the inter-phase thermal imbalance signal, and generate a fourth warning signal if the average temperature deviation of any phase exceeds the allowed range.

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