CN112285428B - Inductance parameter identification method of Buck-boost circuit - Google Patents

Inductance parameter identification method of Buck-boost circuit Download PDF

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CN112285428B
CN112285428B CN201910670133.2A CN201910670133A CN112285428B CN 112285428 B CN112285428 B CN 112285428B CN 201910670133 A CN201910670133 A CN 201910670133A CN 112285428 B CN112285428 B CN 112285428B
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current
voltage
carrier wave
sampling point
inductor
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CN112285428A (en
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房振东
唐剑波
李保健
朱德翔
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Suzhou Fosai New Energy Technology Co ltd
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
    • G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
    • G01R27/26—Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of dc power input into dc power output
    • H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
    • H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
    • H02M3/10—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M3/145—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
    • H02M3/155—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/156—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators
    • H02M3/158—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators including plural semiconductor devices as final control devices for a single load
    • H02M3/1582—Buck-boost converters
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/0003—Details of control, feedback or regulation circuits
    • H02M1/0009—Devices or circuits for detecting current in a converter
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

The invention provides an inductance parameter identification method of a Buck-boost circuit, which comprises the following steps: and configuring a PWM (pulse-width modulation) triggering mode, voltage and current sampling and calculating inductance parameters. The invention can solve the problems that the inductance parameter has errors with the nominal value and cannot be accurately identified due to the influence of temperature and current.

Description

Inductance parameter identification method of Buck-boost circuit
Technical Field
The invention relates to the field of control methods of power electronic devices, in particular to an inductance parameter identification method of a Buck-boost circuit.
Background
The Buck-boost circuit is a DC/DC circuit, can realize voltage conversion from an input end to an output end, and has the characteristics of bidirectional energy flow, controllable output voltage, controllable output current and the like. The Buck-boost topology is a non-isolated bidirectional DC/DC converter, and compared with an isolated topology, the Buck-boost topology has the characteristics of high power density, high conversion efficiency and low cost.
Buck-boost usually adopts the mode that a plurality of Buck-boost are parallelly connected to form a DC/DC module, so that the total DC/DC output current value can be increased, the single-path Buck-boost inductance can be reduced, and the total output current ripple can be greatly reduced by adopting a staggered phase-shifting PWM modulation mode.
The method is widely applied to products such as direct-current power supply equipment for testing, battery charge and discharge control circuits, bidirectional energy storage converters and the like.
The defects and shortcomings of the prior art are as follows:
the Buck-boost inductance parameter is affected by temperature and current, and usually has a certain error from the nominal inductance parameter. The Buck-boost voltage and current control loop parameters need to be modified according to different inductance parameters, and then a good control effect can be achieved. If the loop parameters are designed according to the nominal parameters of the inductor, the loop parameters are not matched, and the best control effect cannot be achieved. Therefore, improvement is urgently needed.
Disclosure of Invention
In order to solve the above technical problems, an object of the present invention is to provide a method for identifying inductance parameters of a Buck-boost circuit, which can solve the problems that the inductance parameters have errors from a nominal value and cannot be accurately identified due to the influence of temperature and current.
In order to achieve the purpose, the inductance parameter identification method of the Buck-boost circuit comprises the following steps of:
the method comprises the following steps: configuring a PWM trigger mode:
(1) Comparing the modulation wave with a carrier wave to determine a PWM signal of a switching tube S1;
(2) The switching tube S2 uses a PWM signal complementary to the PWM signal S1;
step two: voltage and current sampling:
(1) Sampling point 1, when the modulated wave is identical to the carrier wave in size and the carrier wave is in the rising direction, PWM is converted from high level to low level, at the moment, the direction of inductive current is turned, and inductive current is collected at the moment
Figure 206490DEST_PATH_IMAGE001
Bus voltage
Figure 963093DEST_PATH_IMAGE002
Output current of the power supply
Figure 208130DEST_PATH_IMAGE003
；
(2) Sampling point 2, when the modulating wave is the same as the carrier wave and the carrier wave is in the descending direction, PWM is converted from low level to high level, at the moment, the direction of the inductive current is turned, and the inductive current is collected at the moment
Figure 581342DEST_PATH_IMAGE004
Bus voltage
Figure 710972DEST_PATH_IMAGE005
Output current of the power supply
Figure 728607DEST_PATH_IMAGE006
；
(3) Recording the time interval T of the sampling point 1 and the sampling point 2;
step three: and (3) calculating inductance parameters:
(1) There is a voltage-current relationship across the inductor, the inductor voltage
Figure 410124DEST_PATH_IMAGE007
；
(2) During the period of sampling point 1 and sampling point 2, the average value of the bus voltage is: (
Figure 145999DEST_PATH_IMAGE002
+
Figure 675725DEST_PATH_IMAGE005
) (ii)/2, average value of output voltage of
Figure 813445DEST_PATH_IMAGE008
+
Figure 665863DEST_PATH_IMAGE009
)/2；
(3) The bus voltage and the output voltage are the voltages at two ends of the inductor, the difference between the two voltages is used to calculate the voltage on the inductor,
Figure 623455DEST_PATH_IMAGE010
+
Figure 219521DEST_PATH_IMAGE005
)/2-(
Figure 211748DEST_PATH_IMAGE008
+
Figure 969489DEST_PATH_IMAGE009
)/2；
(4) Calculating the current slope to obtain the current slope in the T time period,
Figure 679956DEST_PATH_IMAGE011
= (
Figure 79713DEST_PATH_IMAGE001
-
Figure 519921DEST_PATH_IMAGE004
)/T；
(5) The formula is shown in the simultaneous formula,
Figure 323929DEST_PATH_IMAGE012
+
Figure 380747DEST_PATH_IMAGE005
)/2-(
Figure 53037DEST_PATH_IMAGE008
+
Figure 19856DEST_PATH_IMAGE009
)/2= L(
Figure 116469DEST_PATH_IMAGE001
-
Figure 801529DEST_PATH_IMAGE004
) (ii)/T, to obtain L = T [ solution ]
Figure 418455DEST_PATH_IMAGE012
+
Figure 364414DEST_PATH_IMAGE005
)/2-(
Figure 510224DEST_PATH_IMAGE008
+
Figure 541634DEST_PATH_IMAGE009
)/2]/(
Figure 696672DEST_PATH_IMAGE001
-
Figure 497138DEST_PATH_IMAGE004
)。
Preferably, in the step one (1): when the modulation wave is larger than the carrier wave, the PWM signal of the switch tube S1 is set to be high, and when the modulation wave is smaller than the carrier wave, the PWM signal of the switch tube S1 is set to be low.
Compared with the prior art, the invention has the beneficial effects that:
the method can identify the inductance parameters of the Buck-boost circuit at different current values and different temperatures in real time through online identification of the inductance parameters, provides a basis for selection of optimal loop control parameters, can improve the loop control performance, and can solve the problems that the inductance parameters have errors with the nominal values and cannot be accurately identified due to the influence of temperature and current;
the PWM signal of the switching tube S1 is determined by comparing the modulation wave with the carrier, which is beneficial to rapidly and accurately configuring the PWM triggering mode; expressing the inductor voltage in two ways
Figure 938484DEST_PATH_IMAGE013
: the relation of voltage and current on the inductor and the difference between the bus voltage and the output voltage are combined to determine L, so that accurate and rapid calculation is facilitated, the performance of loop control is ensured, and the problems that the inductance parameter has errors with a nominal value and cannot be accurately identified due to the influence of temperature and current are solved.
Drawings
FIG. 1 is a schematic circuit diagram of an inductance parameter identification method of a Buck-boost circuit according to the invention;
fig. 2 is a schematic diagram of sampling points of the inductance parameter identification method of the Buck-boost circuit of the invention.
Detailed Description
To explain the technical content, structural features, attained objects and effects of the present invention in detail, embodiments are described below in detail with reference to the accompanying drawings.
In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientations and positional relationships indicated in the drawings, which are based on the orientation or positional relationship shown in the drawings, and are used for convenience of description and simplicity of description, but do not indicate or imply that the device or element so referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and therefore should not be construed as limiting the scope of the invention.
The invention provides an inductance parameter identification method of a Buck-boost circuit, which comprises the following steps:
the method comprises the following steps: configuring a PWM trigger mode:
(1) Comparing the modulated wave with the carrier wave to determine a PWM signal of the switching tube S1;
(2) The switching tube S2 uses a PWM signal complementary to the PWM signal S1;
step two: voltage and current sampling:
(1) Sampling point 1, when the modulated wave is identical to carrier wave in size and the carrier wave is in ascending direction, PWM is converted from high level to low level, at this moment, the inductive current direction is turned, and the inductive current is collected at this moment
Figure 332556DEST_PATH_IMAGE001
Bus voltage
Figure 150339DEST_PATH_IMAGE002
Output current of the power supply
Figure 946257DEST_PATH_IMAGE003
；
(2) Sampling point 2, when the modulating wave is the same as the carrier wave and the carrier wave is in the descending direction, PWM is converted from low level to high level, at the moment, the direction of the inductive current is turned, and the inductive current is collected at the moment
Figure 824083DEST_PATH_IMAGE004
Bus voltage
Figure 439872DEST_PATH_IMAGE005
Output current of the power supply
Figure 61346DEST_PATH_IMAGE006
；
(3) Recording the time interval T of the sampling point 1 and the sampling point 2;
step three: calculating inductance parameters:
(1) There is a voltage-current relationship across the inductor, the inductor voltage
Figure 977350DEST_PATH_IMAGE007
；
(2) During the period of sampling point 1 and sampling point 2, the average value of the bus voltage is (
Figure 763428DEST_PATH_IMAGE002
+
Figure 132092DEST_PATH_IMAGE005
) (ii)/2, average value of output voltage of
Figure 291678DEST_PATH_IMAGE008
+
Figure 62188DEST_PATH_IMAGE009
)/2；
(3) The bus voltage and the output voltage are the voltages at two ends of the inductor, the difference between the two voltages is used to calculate the voltage on the inductor,
Figure 157183DEST_PATH_IMAGE010
+
Figure 872198DEST_PATH_IMAGE005
)/2-(
Figure 569896DEST_PATH_IMAGE008
+
Figure 194912DEST_PATH_IMAGE009
)/2；
(4) Calculating the current slope to obtain the current slope of the current in the T time period,
Figure 585442DEST_PATH_IMAGE011
= (
Figure 663119DEST_PATH_IMAGE001
-
Figure 164508DEST_PATH_IMAGE004
)/T；
(5) The formula is shown in the simultaneous formula,
Figure 644031DEST_PATH_IMAGE012
+
Figure 205462DEST_PATH_IMAGE005
)/2-(
Figure 770436DEST_PATH_IMAGE008
+
Figure 75515DEST_PATH_IMAGE009
)/2= L(
Figure 675124DEST_PATH_IMAGE001
-
Figure 427964DEST_PATH_IMAGE004
) [ solution ]/T, to obtain L = T [ [ solution ] ]
Figure 214655DEST_PATH_IMAGE012
+
Figure 323425DEST_PATH_IMAGE005
)/2-(
Figure 777540DEST_PATH_IMAGE008
+
Figure 680774DEST_PATH_IMAGE009
)/2]/(
Figure 954760DEST_PATH_IMAGE001
-
Figure 601642DEST_PATH_IMAGE004
)。
Preferably, in the step one (1): when the modulation wave is larger than the carrier wave, the PWM signal of the switching tube S1 is set to be high, and when the modulation wave is smaller than the carrier wave, the PWM signal of the switching tube S1 is set to be low.
By adopting the technical scheme, the inductance parameters of the Buck-boost circuit can be identified in real time on line, so that the inductance parameters at different current sizes and different temperatures can be identified, a basis is provided for selecting the optimal loop control parameters, the loop control performance can be improved, and the problems that the inductance parameters have errors with the nominal values and cannot be accurately identified due to the influence of temperature current can be solved;
the PWM signal of the switching tube S1 is determined by comparing the modulation wave with the carrier wave, so that the rapid and accurate configuration of a PWM triggering mode is facilitated; the inductor voltage V _ L is expressed by two ways: the relation of voltage and current on the inductor and the difference between the bus voltage and the output voltage are combined to determine L, so that accurate and rapid calculation is facilitated, the performance of loop control is ensured, and the problems that the inductance parameter has errors with a nominal value and cannot be accurately identified due to the influence of temperature and current are solved.
Therefore, the invention is not limited to the specific embodiments and examples shown, but is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

Claims (2)

1. An inductance parameter identification method of a Buck-boost circuit is characterized by comprising the following steps: the method comprises the following steps:
the method comprises the following steps: configuring a PWM trigger mode:
(1) Comparing the modulation wave with a carrier wave to determine a PWM signal of a switching tube S1;
(2) The switching tube S2 uses a PWM signal complementary to S1;
step two: voltage and current sampling:
(1) Sampling point 1, when the modulated wave is identical to carrier wave in size and the carrier wave is in ascending direction, PWM is converted from high level to low level, at this moment, the inductive current direction is turned, and the inductive current is collected at this moment
Figure FDA0004022052350000011
Bus voltage->
Figure FDA0004022052350000012
Output current->
Figure FDA0004022052350000013
(2) Sampling point 2, when the modulating wave is the same as the carrier wave and the carrier wave is in the descending direction, PWM is converted from low level to high level, at the moment, the direction of the inductive current is turned, and the inductive current is collected at the moment
Figure FDA0004022052350000014
Bus voltage->
Figure FDA0004022052350000015
Output current->
Figure FDA0004022052350000016
(3) Recording the time interval T of the sampling point 1 and the sampling point 2;
step three: calculating inductance parameters:
(1) There is a voltage-current relationship across the inductor, the inductor voltage V L ＝L(dI L /dt)；
(2) The average value of the bus voltage in the period of the sampling point 1 and the sampling point 2 is
Figure FDA0004022052350000017
Figure FDA0004022052350000018
The average value of the output voltage is->
Figure FDA0004022052350000019
(3) The bus voltage and the output voltage are the voltages at two ends of the inductor, the difference between the two voltages is used to calculate the voltage on the inductor,
Figure FDA00040220523500000110
(4) Calculating the current slope to obtain the current slope of the current in the T time period,
Figure FDA00040220523500000111
(5) The formula is shown in the simultaneous formula,
Figure FDA00040220523500000112
get->
Figure FDA00040220523500000113
Figure FDA00040220523500000114
The switching tube S1 is connected with the switching tube S2 in series, and an emitter of the switching tube S1 is connected to a collector of the switching tube S2; one end of the inductor is connected between the emitter of the switch tube S1 and the collector of the switch tube S2.
2. The method for identifying the inductance parameter of the Buck-boost circuit as claimed in claim 1, wherein: in the step one (1): when the modulation wave is larger than the carrier wave, the PWM signal of the switch tube S1 is set to be high, and when the modulation wave is smaller than the carrier wave, the PWM signal of the switch tube S1 is set to be low.
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US8450988B2 (en) * 2010-10-05 2013-05-28 Maxim Integrated Products, Inc. Systems and methods for controlling inductive energy in DC-DC converters
CN102714480B (en) * 2011-03-30 2015-03-18 深圳市英威腾电气股份有限公司 Inductance parameter identification method of synchronous motor and implementation system thereof
CN102621399B (en) * 2012-04-23 2014-07-02 欧阳斌林 Inductance measuring method based on switching circuit
CN103454481B (en) * 2013-09-10 2015-10-28 深圳市英威腾电气股份有限公司 A kind of BOOST inductive current sampling correcting method
CN103954845B (en) * 2014-04-11 2017-01-04 西南交通大学 A kind of medium-and low-speed maglev train levitating electromagnet inductance parameters online test method based on resistance
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CN106487205B (en) * 2016-09-23 2019-01-29 矽力杰半导体技术(杭州)有限公司 Parameter identification circuit, method and the power-supply system using it
CN109067176B (en) * 2018-08-02 2020-04-07 哈尔滨工程大学 Current sharing control method for maximum inductive current of DC/DC converter

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