CN110277917B - Rail transit power supply system, bidirectional DC-DC converter thereof and control method - Google Patents
Rail transit power supply system, bidirectional DC-DC converter thereof and control method Download PDFInfo
- Publication number
- CN110277917B CN110277917B CN201810205943.6A CN201810205943A CN110277917B CN 110277917 B CN110277917 B CN 110277917B CN 201810205943 A CN201810205943 A CN 201810205943A CN 110277917 B CN110277917 B CN 110277917B
- Authority
- CN
- China
- Prior art keywords
- conversion module
- switching tube
- control signal
- voltage
- module
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- 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
- H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
- H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
- H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
- H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
- H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/33569—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
- H02M3/33576—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements having at least one active switching element at the secondary side of an isolation transformer
- H02M3/33584—Bidirectional 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
Abstract
The invention discloses a rail transit power supply system, a bidirectional DC-DC converter and a control method thereof, wherein the method comprises the following steps: sampling an output current and an output voltage of any one of the first DC-DC conversion module and the second DC-DC conversion module; and generating a control signal according to the output current and the output voltage sampled by the sampling module, and respectively controlling the first DC-DC conversion module and the second DC-DC conversion module according to the control signal in a synchronous driving mode to balance the voltage of the first node, so that the output power can be increased by connecting two groups of DC-DC conversion modules in parallel, and the voltage of the first node can be balanced to ensure the stability of the front-end capacitor voltage.
Description
Technical Field
The invention relates to the technical field of power electronics, in particular to a bidirectional DC-DC converter, a rail transit power supply system and a control method of the bidirectional DC-DC converter.
Background
The bidirectional DC-DC converter has been an important component in the power electronics field, and with the development of the vehicle field, the DC-DC converter has also become one of the important parts on the train. To meet the output power demand, the related art needs improvement.
Disclosure of Invention
The present invention is directed to solving, at least to some extent, one of the technical problems in the related art. Therefore, an object of the present invention is to provide a control method for a bidirectional DC-DC converter, which increases output power by connecting two sets of DC-DC conversion modules in parallel and can balance the voltage of the first node to ensure the stability of the front-end capacitor voltage.
Another object of the present invention is to provide a bidirectional DC-DC converter.
Still another object of the present invention is to provide a rail transit power supply system.
In order to achieve the above object, in an embodiment of an aspect of the present invention, a control method of a bidirectional DC-DC converter includes a first capacitor, a second capacitor, a first DC-DC conversion module, and a second DC-DC conversion module, where the first capacitor is connected in series with the second capacitor and then connected to two ends of a DC power source in parallel, a first node is provided between the first capacitor and the second capacitor, a first end and a second end of the first DC-DC conversion module are respectively connected to two ends of the first capacitor, a first end and a second end of the second DC-DC conversion module are respectively connected to two ends of the second capacitor, a third end of the second DC-DC conversion module is connected to a third end of the first DC-DC conversion module, a fourth end of the second DC-DC conversion module is connected to a fourth end of the first DC-DC conversion module, the control method comprises the following steps: sampling an output current and an output voltage of any one of the first DC-DC conversion module and the second DC-DC conversion module; and generating a control signal according to the output current and the output voltage sampled by the sampling module, and respectively controlling the first DC-DC conversion module and the second DC-DC conversion module in a synchronous driving mode according to the control signal so as to balance the voltage of the first node.
According to the control method of the bidirectional DC-DC converter provided by the embodiment of the invention, the output current and the output voltage of any one DC-DC conversion module in the first DC-DC conversion module and the second DC-DC conversion module are sampled, then the control signal is generated according to the output current and the output voltage sampled by the sampling module, and the first DC-DC conversion module and the second DC-DC conversion module are respectively controlled in a synchronous driving mode according to the control signal so as to control the voltage of the first node. Therefore, the control method provided by the embodiment of the invention can increase the output power by connecting the two groups of DC-DC conversion modules in parallel, effectively balance the voltage of the first node, avoid the voltage of the front-end capacitor from being too high, reduce the voltage withstanding value required by the front-end capacitor and further reduce the production cost.
According to an embodiment of the present invention, the method for controlling a bidirectional DC-DC converter further includes: and feeding back the voltage of the first node, and compensating the control signal according to the fed back voltage of the first node, so as to control the first DC-DC conversion module and the second DC-DC conversion module according to the compensated control signal, so that the voltage of the first node is kept balanced.
According to an embodiment of the present invention, the frequency and duty ratio of the control signal output to the first DC-DC conversion module and the second DC-DC conversion module are the same.
According to an embodiment of the present invention, compensating the control signal according to the fed back voltage of the first node includes: and generating a correction frequency according to the fed back voltage of the first node, and superposing the correction frequency and the frequency of the control signal.
According to an embodiment of the present invention, the first capacitor and the second capacitor have the same specification and model, and the first DC-DC conversion module and the second DC-DC conversion module have the same hardware parameters.
In order to achieve the above object, another embodiment of the present invention provides a bidirectional DC-DC converter, including: the first capacitor and the second capacitor are connected in series and then connected to two ends of a direct current power supply in parallel, and a first node is arranged between the first capacitor and the second capacitor; a first DC-DC conversion module, a first terminal and a second terminal of which are respectively connected to two terminals of the first capacitor; a first end and a second end of the second DC-DC conversion module are respectively connected to two ends of the second capacitor, a third end of the second DC-DC conversion module is connected to a third end of the first DC-DC conversion module, and a fourth end of the second DC-DC conversion module is connected to a fourth end of the first DC-DC conversion module; a sampling module for sampling an output current and an output voltage of any one of the first DC-DC conversion module and the second DC-DC conversion module; and the control module is used for generating a control signal according to the output current and the output voltage sampled by the sampling module, and respectively controlling the first DC-DC conversion module and the second DC-DC conversion module in a synchronous driving mode according to the control signal so as to balance the voltage of the first node.
According to the bidirectional DC-DC converter provided in the embodiment of the present invention, the first capacitor and the second capacitor are connected in series and then connected in parallel to two ends of the DC power supply, the first capacitor and the second capacitor have a first node therebetween, the first end and the second end of the first DC-DC conversion module are respectively connected to two ends of the first capacitor, the first end and the second end of the second DC-DC conversion module are respectively connected to two ends of the second capacitor, the third end of the second DC-DC conversion module is connected to the third end of the first DC-DC conversion module, the fourth end of the second DC-DC conversion module is connected to the fourth end of the first DC-DC conversion module, the sampling module samples the output current and the output voltage of any one of the first DC-DC conversion module and the second DC-DC conversion module, the control module generates the control signal according to the output current and the output voltage sampled by the sampling module, and the first DC-DC conversion module and the second DC-DC conversion module are respectively controlled in a synchronous driving mode according to the control signal so as to balance the voltage of the first node. Therefore, the converter provided by the embodiment of the invention can increase the output power by connecting the two groups of DC-DC conversion modules in parallel, effectively balance the voltage of the first node, avoid the voltage of the front-end capacitor from being overlarge, reduce the voltage withstanding value required by the front-end capacitor and further reduce the production cost.
According to an embodiment of the present invention, the bidirectional DC-DC converter further includes: the control module is further configured to compensate the control signal according to the voltage of the first node, so as to control the first DC-DC conversion module and the second DC-DC conversion module according to the compensated control signal, so that the voltage of the first node is kept balanced.
According to an embodiment of the present invention, the frequency and duty ratio of the control signal output to the first DC-DC conversion module and the second DC-DC conversion module are the same.
According to an embodiment of the present invention, the first capacitor and the second capacitor have the same specification and model, and the first DC-DC conversion module and the second DC-DC conversion module have the same hardware parameters.
According to an embodiment of the present invention, when the control module compensates the control signal, a correction frequency is generated according to the voltage of the first node, and the correction frequency is superimposed on the frequency of the control signal.
In order to achieve the above object, in another embodiment of the present invention, a rail transit power supply system is provided, which includes the bidirectional DC-DC converter.
According to the rail transit power supply system provided by the embodiment of the invention, through the bidirectional DC-DC converter, the output power can be increased through the parallel connection of the two groups of DC-DC conversion modules, the voltage of the first node can be effectively balanced, the voltage of the front-end capacitor is prevented from being too large, the withstand voltage value required by the front-end capacitor is reduced, and the production cost is further reduced.
Drawings
Fig. 1 is a flowchart of a control method of a bidirectional DC-DC converter according to an embodiment of the present invention.
FIG. 2 is a circuit schematic of a bi-directional DC-DC converter according to one embodiment of the present invention;
FIG. 3 is a block schematic diagram of a bidirectional DC-DC converter according to an embodiment of the present invention;
FIG. 4 is a block schematic diagram of a bidirectional DC to DC converter in accordance with one embodiment of the present invention;
FIG. 5 is a control schematic of a bi-directional DC-DC converter according to one embodiment of the present invention;
fig. 6 is a block diagram of a rail transit power supply system according to an embodiment of the present invention.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.
The bidirectional DC-DC converter, the rail transit power supply system, and the control method of the bidirectional DC-DC converter according to the embodiments of the present invention are described below with reference to the drawings.
Fig. 1 is a control method of a bidirectional DC-DC converter according to an embodiment of the present invention. As shown in fig. 2, the bidirectional DC-DC converter includes a first capacitor, a second capacitor, a first DC-DC conversion module, and a second DC-DC conversion module, where the first capacitor is connected in series with the second capacitor and then connected in parallel to two ends of the DC power supply, a first node is provided between the first capacitor and the second capacitor, a first end and a second end of the first DC-DC conversion module are respectively connected to two ends of the first capacitor, a first end and a second end of the second DC-DC conversion module are respectively connected to two ends of the second capacitor, a third end of the second DC-DC conversion module is connected to a third end of the first DC-DC conversion module, and a fourth end of the second DC-DC conversion module is connected to a fourth end of the first DC-DC conversion module. In the embodiment of the invention, the bidirectional DC-DC converter is a 1500V bidirectional DC-DC converter. The first DC-DC conversion module and the second DC-DC conversion module are both bidirectional H-bridge direct-current chopper circuits.
As shown in fig. 1, a control method of a bidirectional DC-DC converter according to an embodiment of the present invention includes the following steps:
s1: the output current and the output voltage of any one of the first DC-DC conversion module and the second DC-DC conversion module are sampled.
Specifically, the output current and the output voltage of any one of the first DC-DC conversion module and the second DC-DC conversion module may be sampled by the sampling module. For example, the sampling module may be connected to an output of the first DC-DC conversion module to sample the output current and the output voltage of the first DC-DC conversion.
S2: and generating a control signal according to the output current and the output voltage sampled by the sampling module, and respectively controlling the first DC-DC conversion module and the second DC-DC conversion module in a synchronous driving mode according to the control signal so as to balance the voltage of the first node.
It should be understood that synchronous driving is simultaneous control, that is, the first DC-DC conversion module and the second DC-DC conversion module are controlled in a synchronous driving manner according to the control signal, that is, the first DC-DC conversion module and the second DC-DC conversion module are simultaneously controlled according to the control signal, and, in particular, as shown in fig. 2, the first switch tube Q1 and the fourth switch tube Q4 in the first DC-DC conversion module can be driven simultaneously when conducting in the forward direction according to the control signal, and the ninth switching tube Q9 and the twelfth switching tube Q12 in the second DC-DC conversion module are simultaneously turned on or off, the third switch tube Q3 and the second switch tube Q2 in the first DC-DC conversion module can be driven simultaneously when conducting reversely, and the tenth switching tube Q10 and the eleventh switching tube Q11 in the second DC-DC conversion module are simultaneously turned on or off.
According to one embodiment of the invention, the specification models of the first capacitor and the second capacitor are the same, and the hardware parameters of the first DC-DC conversion module and the second DC-DC conversion module are the same.
It should be noted that, the first capacitor and the second capacitor are voltage dividing capacitors, that is, the first capacitor and the second capacitor divide the voltage of the DC power supply equally to provide the same voltage to the first DC-DC conversion module and the second DC-DC conversion module, that is, the voltage at the first node is balanced, but when the output powers of the first DC-DC conversion module and the second DC-DC conversion module are not consistent, the voltages of the two voltage dividing capacitors may deviate, that is, the voltages at the midpoints are unbalanced, and therefore, the first DC-DC conversion module and the second DC-DC conversion module may be synchronously driven according to the control signal to keep the voltages at the first node balanced.
That is, the output current and the output voltage of any one of the first DC-DC conversion module and the second DC-DC conversion module may be sampled by the sampling module, generating a control signal according to the output current and the output voltage sampled by the sampling module, and respectively controlling the first DC-DC conversion module and the second DC-DC conversion module in a synchronous driving mode according to the control signal, namely, the first DC-DC conversion module and the second DC-DC conversion module are controlled according to the control signal, and output powers of the first DC-DC conversion module and the second DC-DC conversion module are made to be identical, and specifically, frequencies and duty ratios of control signals output to the first DC-DC conversion module and the second DC-DC conversion module are made to be identical, thereby balancing voltages of the first nodes.
Therefore, according to the embodiment of the invention, the output power is increased in a mode that two groups of DC-DC conversion modules are connected in parallel, then the first DC-DC conversion module and the second DC-DC conversion module are synchronously driven according to the output current and the output voltage of the first DC-DC conversion module or the second DC-DC conversion module, the voltage of the first node can be balanced, namely, the voltage of the first capacitor and the voltage of the second capacitor are ensured to be kept at one half of the voltage of the direct-current power supply, so that the withstand voltage values of the first capacitor and the second capacitor are half of the voltage of the direct-current power supply, the first capacitor and the second capacitor can be selected according to the half of the voltage of the direct-current power supply, and the production cost is effectively reduced.
According to an embodiment of the present invention, the control method of the bidirectional DC-DC converter further includes: and feeding back the voltage of the first node, and compensating the control signal according to the fed back voltage of the first node so as to control the first DC-DC conversion module and the second DC-DC conversion module according to the compensated control signal, so that the voltage of the first node is kept balanced.
It should be noted that, due to the problems that the electrical component is affected by actual processes and materials, etc., the parameters of the component may be deviated, and further, the voltage of the first node may be unbalanced. Based on this, in order to solve the voltage unbalance that leads to because the components and parts parameter, increase the control link of a midpoint feedforward to make the voltage of first node keep balance.
Specifically, a midpoint feedback module may be added to the 1500V bidirectional DC-DC converter, and the midpoint feedback module may collect and feed back the voltage of the first node, compensate the control signal according to the voltage of the first node, and control the first DC-DC conversion module and the second DC-DC conversion module according to the compensated control signal, so as to keep the voltage of the first node balanced.
Wherein, compensating the control signal according to the fed-back voltage of the first node comprises: and generating a correction frequency according to the fed-back voltage of the first node, and superposing the correction frequency and the frequency of the control signal.
For example, the sampling module may sample an output current and an output voltage of the first DC-DC conversion module, the midpoint voltage feedback module detects and feeds back a voltage of the first node, generates a control signal according to the output current and the output voltage sampled by the sampling module, compensates according to the voltage of the first node to generate a compensated control signal, controls the first DC-DC conversion module according to the control signal, and controls the second DC-DC conversion module according to the compensated control signal.
In summary, according to the control method of the bidirectional DC-DC converter provided in the embodiment of the present invention, the output current and the output voltage of any one of the first DC-DC conversion module and the second DC-DC conversion module are sampled, then the control signal is generated according to the output current and the output voltage sampled by the sampling module, and the first DC-DC conversion module and the second DC-DC conversion module are respectively controlled in a synchronous driving manner according to the control signal, so as to control the voltage of the first node. Therefore, the control method provided by the embodiment of the invention can increase the output power by connecting the two groups of DC-DC conversion modules in parallel, effectively balance the voltage of the first node, avoid the voltage of the front-end capacitor from being too high, reduce the voltage withstanding value required by the front-end capacitor and further reduce the production cost.
Fig. 3 is a block schematic diagram of a bidirectional DC-DC converter according to an embodiment of the invention. As shown in fig. 2 and 3, the bidirectional DC-DC converter of the embodiment of the present invention includes: the circuit comprises a first capacitor C1, a second capacitor C2, a first DC-DC conversion module 10, a second DC-DC conversion module 20, a sampling module 30 and a control module 40.
The first capacitor C1 and the second capacitor C2 are connected in series and then connected to two ends of the direct current power supply DC in parallel; a first node J1 is arranged between the first capacitor C1 and the second capacitor C2, the first terminal 11 and the second terminal 12 of the first DC-DC conversion module 10 are respectively connected to two ends of the first capacitor C1, the first terminal 21 and the second terminal 22 of the second DC-DC conversion module 20 are respectively connected to two ends of the second capacitor C2, the third terminal 23 of the second DC-DC conversion module 20 is connected to the third terminal 13 of the first DC-DC conversion module 10, and the fourth terminal 24 of the second DC-DC conversion module 20 is connected to the fourth terminal 14 of the first DC-DC conversion module; the sampling module 30 is configured to sample an output current and an output voltage of any one of the first DC-DC conversion module 10 and the second DC-DC conversion module 20; the control module 40 is configured to generate a control signal according to the output current and the output voltage sampled by the sampling module 30, and control the first DC-DC conversion module 10 and the second DC-DC conversion module 20 in a synchronous driving manner according to the control signal, so as to balance the voltage at the first node J1.
The sampling module 30 may be connected to an output terminal of the first DC-DC conversion module 10 to sample an output current and an output voltage of the first DC-DC conversion module 10.
In the embodiment of the present invention, the bidirectional DC-DC converter is a 1500V bidirectional DC-DC converter, and the first DC-DC conversion module 10 and the second DC-DC conversion module 20 are both bidirectional H-bridge direct current chopper circuits.
According to an embodiment of the invention, the first capacitor C1 and the second capacitor C2 have the same specification model, and the hardware parameters of the first DC-DC conversion module 10 and the second DC-DC conversion module 20 are the same.
It should be noted that the first capacitor C1 and the second capacitor C2 are voltage dividing capacitors, that is, the first capacitor C1 and the second capacitor C2 both divide the voltage of the DC power DC to provide the same voltage to the first DC-DC conversion module 10 and the second DC-DC conversion module 20, that is, the voltage at the first node is balanced, but when the output powers of the first DC-DC conversion module 10 and the second DC-DC conversion module 20 are not consistent, the voltages of the two voltage dividing capacitors may be deviated, that is, the voltages at the midpoint are unbalanced, and therefore, the first DC-DC conversion module 10 and the second DC-DC conversion module 20 may be synchronously driven to keep the voltages at the first node J1 balanced.
It should be understood that synchronous driving is simultaneous control, that is, the first DC-DC conversion module and the second DC-DC conversion module are controlled in a synchronous driving manner according to the control signal, that is, the first DC-DC conversion module and the second DC-DC conversion module are simultaneously controlled according to the control signal, and, particularly, the first switch tube Q1 and the fourth switch tube Q4 in the first DC-DC conversion module can be driven simultaneously when conducting in the forward direction according to the control signal, and the ninth switching tube Q9 and the twelfth switching tube Q12 in the second DC-DC conversion module are simultaneously turned on or off, the third switch tube Q3 and the second switch tube Q2 in the first DC-DC conversion module can be driven simultaneously when conducting reversely, and the tenth switching tube Q10 and the eleventh switching tube Q11 in the second DC-DC conversion module are simultaneously turned on or off.
That is, the sampling module 30 may sample the output current and the output voltage of any one of the first DC-DC conversion module 10 and the second DC-DC conversion module 20, the control module 40 receives the output current and the output voltage sampled by the sampling module 30 and generates a control signal according to the output current and the output voltage, the control module 40 controls the first DC-DC conversion module 10 and the second DC-DC conversion module 20 in a synchronous driving manner according to the control signal, that is, the control module 40 controls the first DC-DC conversion module 10 and the second DC-DC conversion module 20 simultaneously according to the control signal, and makes the output powers of the first DC-DC conversion module 10 and the second DC-DC conversion module 20 consistent, specifically, the frequency and the duty ratio of the control signal output to the first DC-DC conversion module 10 and the second DC-DC conversion module 20 are the same, thereby balancing the voltage of the first node J1.
Therefore, the output power is increased in a mode that the two groups of DC-DC conversion modules are connected in parallel, the first DC-DC conversion module and the second DC-DC conversion module are synchronously driven according to the output current and the output voltage of the first DC-DC conversion module or the second DC-DC conversion module, the voltage of the first node can be balanced, namely, the voltage of the first capacitor and the voltage of the second capacitor are guaranteed to be kept at one half of the voltage of a direct-current power supply, the withstand voltage value of the first capacitor and the withstand voltage value of the second capacitor are half of the voltage of the direct-current power supply, the first capacitor and the second capacitor can be selected according to the half of the voltage of the direct-current power supply, and the production cost is effectively reduced.
According to an embodiment of the present invention, as shown in fig. 4, the bidirectional DC-DC converter further includes a midpoint voltage feedback module 50, the midpoint voltage feedback module 50 is configured to feed back the voltage of the first node J1 to the control module 40, and the control module 40 is further configured to compensate the control signal according to the voltage of the first node J1, so as to control the first DC-DC conversion module 10 and the second DC-DC conversion module 20 according to the compensated control signal, so as to balance the voltages of the first node J1.
It should be noted that, since the electrical components are affected by actual processes and materials, the parameters of the components may be deviated, and thus the voltage at the first node J1 may be unbalanced. Based on this, in order to solve the voltage imbalance caused by the device parameters, a control link of midpoint feed forward is added to keep the voltage of the first node J1 balanced.
Specifically, as shown in fig. 4, a midpoint voltage feedback module 50 is added to the 1500V bidirectional DC-DC converter, the midpoint voltage feedback module 50 collects the voltage of the first node J1 and feeds the voltage back to the control module 40, and the control module 40 receives the voltage of the first node J1 sent by the midpoint voltage feedback module 50 and compensates the control signal according to the voltage of the first node J1, so as to control the first DC-DC conversion module 10 and the second DC-DC conversion module 20 according to the compensated control signal, so as to keep the voltage of the first node J1 balanced.
For example, as shown in fig. 4, the sampling module 30 may sample an output current and an output voltage of the first DC-DC conversion module 10 and send the output current and the output voltage to the control module 40, the midpoint voltage feedback module 50 detects a voltage of the first node J1 and feeds the voltage back to the control module 40, the control module 40 generates a control signal according to the output current and the output voltage sampled by the sampling module 30, compensates the control signal according to the voltage of the first node J1 detected by the midpoint voltage feedback module 50 to generate a compensated control signal, and the control module 40 may control the first DC-DC conversion module 10 according to the control signal and control the second DC-DC conversion module 20 according to the compensated control signal.
According to an embodiment of the present invention, as shown in fig. 5, when the control module 40 compensates the control signal, a correction frequency is generated according to the voltage of the first node J1, and the correction frequency is superimposed on the frequency of the control signal.
That is, the control module 40 receives the voltage at the first node J1 and generates a correction frequency according to the voltage at the first node J1, the control module 40 superimposes the correction frequency with the frequency of the control signal to generate a compensated control signal, and then controls the first DC-DC conversion module 10 and the second DC-DC conversion module according to the compensated control signal to balance the voltage at the first node J1.
In summary, according to the bidirectional DC-DC converter provided in the embodiment of the present invention, the first capacitor and the second capacitor are connected in series and then connected in parallel to two ends of the DC power supply, the first node is provided between the first capacitor and the second capacitor, the first end and the second end of the first DC-DC conversion module are connected in parallel to two ends of the first capacitor, the first end and the second end of the second DC-DC conversion module are connected in parallel to two ends of the second capacitor, the third end of the second DC-DC conversion module is connected to the third end of the first DC-DC conversion module, the fourth end of the second DC-DC conversion module is connected to the fourth end of the first DC-DC conversion module, the sampling module samples the output current and the output voltage of any one of the first DC-DC conversion module and the second DC-DC conversion module, the control module generates the control signal according to the output current and the output voltage sampled by the sampling module, and the first DC-DC conversion module and the second DC-DC conversion module are respectively controlled in a synchronous driving mode according to the control signal so as to balance the voltage of the first node. Therefore, the converter provided by the embodiment of the invention can increase the output power by connecting the two groups of DC-DC conversion modules in parallel, effectively balance the voltage of the first node, avoid the voltage of the front-end capacitor from being overlarge, reduce the voltage withstanding value required by the front-end capacitor and further reduce the production cost.
Fig. 6 is a rail transit power supply system according to an embodiment of the present invention. As shown in fig. 6, the rail transit power supply system 200 of the embodiment of the present invention includes a bidirectional DC-DC converter 100.
According to the rail transit power supply system provided by the embodiment of the invention, through the bidirectional DC-DC converter, the output power can be increased through the parallel connection of the two groups of DC-DC conversion modules, the voltage of the first node can be effectively balanced, the voltage of the front-end capacitor is prevented from being too large, the withstand voltage value required by the front-end capacitor is reduced, and the production cost is further reduced.
In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.
Claims (7)
1. A control method of a bidirectional DC-DC converter is characterized in that the bidirectional DC-DC converter comprises a first capacitor, a second capacitor, a first DC-DC conversion module and a second DC-DC conversion module, the first capacitor and the second capacitor are connected in series and then are connected to two ends of a direct current power supply in parallel, a first node is arranged between the first capacitor and the second capacitor, a first end and a second end of the first DC-DC conversion module are respectively connected to two ends of the first capacitor, a first end and a second end of the second DC-DC conversion module are respectively connected to two ends of the second capacitor, a third end of the second DC-DC conversion module is connected with a third end of the first DC-DC conversion module, a fourth end of the second DC-DC conversion module is connected with a fourth end of the first DC-DC conversion module, the control method comprises the following steps:
sampling an output current and an output voltage of any one of the first DC-DC conversion module and the second DC-DC conversion module;
generating a control signal according to an output current and an output voltage sampled by a sampling module, and controlling the first DC-DC conversion module and the second DC-DC conversion module respectively according to the control signal in a synchronous driving manner to balance the voltage of the first node, wherein the controlling the first DC-DC conversion module and the second DC-DC conversion module respectively in a synchronous driving manner according to the control signal comprises: according to the control signal, a first switching tube and a fourth switching tube in the first DC-DC conversion module are simultaneously driven to be simultaneously turned on or turned off when the first DC-DC conversion module is conducted in the forward direction, a ninth switching tube and a twelfth switching tube in the second DC-DC conversion module are simultaneously driven to be simultaneously turned on or turned off when the second DC-DC conversion module is conducted in the reverse direction, and a tenth switching tube and an eleventh switching tube in the second DC-DC conversion module are simultaneously driven to be turned on or turned off when the second DC-DC conversion module is conducted in the reverse direction; the source electrode of the first switching tube is connected with the drain electrode of the second switching tube, the source electrode of the second switching tube is connected with the source electrode of the fourth switching tube, the drain electrode of the fourth switching tube is connected with the first end of the sampling module, the second end of the sampling module is connected with the source electrode of the third switching tube, and the drain electrode of the third switching tube is connected with the drain electrode of the first switching tube; the drain electrode of the first switching tube is the first end of the first DC-DC conversion module, and the source electrode of the second switching tube is the second end of the first DC-DC conversion module; the source electrode of the ninth switching tube is connected with the drain electrode of the tenth switching tube, the source electrode of the tenth switching tube is connected with the source electrode of the twelfth switching tube, the drain electrode of the twelfth switching tube is connected with the first end of the sampling module, the second end of the sampling module is connected with the source electrode of the eleventh switching tube, and the drain electrode of the eleventh switching tube is connected with the drain electrode of the ninth switching tube; a drain electrode of the ninth switching tube is a first end of the second DC-DC conversion module, and a source electrode of the tenth switching tube is a second end of the second DC-DC conversion module;
feeding back the voltage of the first node, compensating the control signal according to the fed back voltage of the first node to generate a compensated control signal, controlling the first DC-DC conversion module according to the control signal, and controlling the second DC-DC conversion module according to the compensated control signal to keep the voltage of the first node balanced, wherein compensating the control signal according to the fed back voltage of the first node to generate the compensated control signal comprises: and generating a correction frequency according to the fed-back voltage of the first node, and superposing the correction frequency and the frequency of the control signal to generate the compensated control signal.
2. The control method of a bidirectional DC-DC converter according to claim 1, wherein the frequency and duty ratio of the control signal output to the first DC-DC conversion module and the second DC-DC conversion module are the same.
3. The method according to claim 1 or 2, wherein the first capacitor and the second capacitor have the same specification model, and the hardware parameters of the first DC-DC conversion module and the second DC-DC conversion module are the same.
4. A bidirectional DC-DC converter, comprising:
the first capacitor and the second capacitor are connected in series and then connected to two ends of a direct current power supply in parallel, and a first node is arranged between the first capacitor and the second capacitor;
a first DC-DC conversion module, a first terminal and a second terminal of which are respectively connected to two terminals of the first capacitor;
a first end and a second end of the second DC-DC conversion module are respectively connected to two ends of the second capacitor, a third end of the second DC-DC conversion module is connected to a third end of the first DC-DC conversion module, and a fourth end of the second DC-DC conversion module is connected to a fourth end of the first DC-DC conversion module;
a sampling module for sampling an output current and an output voltage of any one of the first DC-DC conversion module and the second DC-DC conversion module;
the control module is used for controlling the first DC-DC conversion module and the second DC-DC conversion module to carry out voltage conversion; the control module is further configured to generate a control signal according to the output current and the output voltage sampled by the sampling module, and control the first DC-DC conversion module and the second DC-DC conversion module according to the control signal in a synchronous driving manner, so as to balance the voltage of the first node, where the control module controls the first DC-DC conversion module and the second DC-DC conversion module according to the control signal in a synchronous driving manner, respectively, and includes: according to the control signal, a first switching tube and a fourth switching tube in the first DC-DC conversion module are simultaneously driven to be simultaneously turned on or turned off when the first DC-DC conversion module is conducted in the forward direction, a ninth switching tube and a twelfth switching tube in the second DC-DC conversion module are simultaneously driven to be simultaneously turned on or turned off when the second DC-DC conversion module is conducted in the reverse direction, and a tenth switching tube and an eleventh switching tube in the second DC-DC conversion module are simultaneously driven to be turned on or turned off when the second DC-DC conversion module is conducted in the reverse direction; the source electrode of the first switching tube is connected with the drain electrode of the second switching tube, the source electrode of the second switching tube is connected with the source electrode of the fourth switching tube, the drain electrode of the fourth switching tube is connected with the first end of the sampling module, the second end of the sampling module is connected with the source electrode of the third switching tube, and the drain electrode of the third switching tube is connected with the drain electrode of the first switching tube; the drain electrode of the first switching tube is the first end of the first DC-DC conversion module, and the source electrode of the second switching tube is the second end of the first DC-DC conversion module; the source electrode of the ninth switching tube is connected with the drain electrode of the tenth switching tube, the source electrode of the tenth switching tube is connected with the source electrode of the twelfth switching tube, the drain electrode of the twelfth switching tube is connected with the first end of the sampling module, the second end of the sampling module is connected with the source electrode of the eleventh switching tube, and the drain electrode of the eleventh switching tube is connected with the drain electrode of the ninth switching tube; a drain electrode of the ninth switching tube is a first end of the second DC-DC conversion module, and a source electrode of the tenth switching tube is a second end of the second DC-DC conversion module;
a midpoint voltage feedback module, configured to collect a voltage of the first node and feed the voltage of the first node back to the control module, where the control module is further configured to compensate the control signal according to the voltage of the first node to generate a compensated control signal, then control the first DC-DC conversion module according to the control signal, and control the second DC-DC conversion module according to the compensated control signal to keep the voltage of the first node balanced, where the compensation of the control signal by the control module according to the fed-back voltage of the first node to generate the compensated control signal includes: and generating a correction frequency according to the fed-back voltage of the first node, and superposing the correction frequency and the frequency of the control signal to generate the compensated control signal.
5. The bidirectional DC-DC converter of claim 4, wherein the frequency and duty cycle of the control signals output to the first DC-DC conversion module and the second DC-DC conversion module are the same.
6. The bidirectional DC-DC converter according to claim 4 or 5, wherein the first capacitor and the second capacitor are the same in specification model, and the hardware parameters of the first DC-DC conversion module and the second DC-DC conversion module are the same.
7. A rail transit power supply system comprising a bidirectional DC-DC converter according to any one of claims 4 to 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810205943.6A CN110277917B (en) | 2018-03-13 | 2018-03-13 | Rail transit power supply system, bidirectional DC-DC converter thereof and control method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810205943.6A CN110277917B (en) | 2018-03-13 | 2018-03-13 | Rail transit power supply system, bidirectional DC-DC converter thereof and control method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110277917A CN110277917A (en) | 2019-09-24 |
| CN110277917B true CN110277917B (en) | 2021-06-18 |
Family
ID=67958170
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810205943.6A Active CN110277917B (en) | 2018-03-13 | 2018-03-13 | Rail transit power supply system, bidirectional DC-DC converter thereof and control method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110277917B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101345473A (en) * | 2008-05-04 | 2009-01-14 | 南京航空航天大学 | Input-series-output-parallel automatic voltage equalizing DC transformer based on full-bridge topological structure |
| CN201336757Y (en) * | 2009-01-22 | 2009-10-28 | 陈咸丰 | Multi-way constant-current power supply used for high-power LED light source |
| CN107276417A (en) * | 2017-08-09 | 2017-10-20 | 广州金升阳科技有限公司 | A kind of power-supply system |
| CN107528491A (en) * | 2017-08-28 | 2017-12-29 | 中国矿业大学 | A kind of cascaded H-bridges multi-level converter and its control method |
| CN107546959A (en) * | 2016-06-23 | 2018-01-05 | 中兴通讯股份有限公司 | A kind of Switching Power Supply, electronic equipment and Switching Power Supply control method |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8536735B2 (en) * | 2009-02-27 | 2013-09-17 | Delta Electronics (Shanghai) Co., Ltd. | Converter with input voltage balance circuit |
-
2018
- 2018-03-13 CN CN201810205943.6A patent/CN110277917B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101345473A (en) * | 2008-05-04 | 2009-01-14 | 南京航空航天大学 | Input-series-output-parallel automatic voltage equalizing DC transformer based on full-bridge topological structure |
| CN201336757Y (en) * | 2009-01-22 | 2009-10-28 | 陈咸丰 | Multi-way constant-current power supply used for high-power LED light source |
| CN107546959A (en) * | 2016-06-23 | 2018-01-05 | 中兴通讯股份有限公司 | A kind of Switching Power Supply, electronic equipment and Switching Power Supply control method |
| CN107276417A (en) * | 2017-08-09 | 2017-10-20 | 广州金升阳科技有限公司 | A kind of power-supply system |
| CN107528491A (en) * | 2017-08-28 | 2017-12-29 | 中国矿业大学 | A kind of cascaded H-bridges multi-level converter and its control method |
Non-Patent Citations (1)
| Title |
|---|
| 基于输入串联输出并联的列车充电机研究;韩冰 等;《电力电子技术》;20171130;第51卷(第11期);第111-113页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110277917A (en) | 2019-09-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6297616B1 (en) | Charge and discharge system for electric power storage equipment | |
| TWI584548B (en) | Dc link module and method for operating the same | |
| US10361573B2 (en) | Battery pack | |
| US20100135054A1 (en) | Inverter for feeding electric energy into a power supply system | |
| US8188723B2 (en) | Switching converter and method to control a switching converter | |
| CN101540510B (en) | Method for eliminating secondary pulsation interference on middle DC side in two-stage grid-connected system | |
| WO2009031673A1 (en) | Charge control circuit | |
| CN103219901A (en) | Alternating current/direct current (AC/DC) converter control circuit and AC/DC converter using same | |
| US20090046491A1 (en) | Inverter | |
| US10031190B2 (en) | Voltage detection device | |
| CN103731048A (en) | Regenerative voltage doubler rectifier, voltage sag/swell correction apparatus and operating methods | |
| TW201014134A (en) | Switching power supply circuit | |
| US9882381B2 (en) | Photovoltaic inverter | |
| JP2013121211A (en) | Power supply system | |
| CN102270885A (en) | Method and arrangement for balancing voltages of series connection of storage units for electrical energy | |
| CN110277917B (en) | Rail transit power supply system, bidirectional DC-DC converter thereof and control method | |
| EP3378150A1 (en) | Active filter topology for cascaded inverters | |
| CN104584405A (en) | Switching control circuit and switching power device | |
| US8902620B2 (en) | Power conditioner | |
| JP2018508172A (en) | DC / DC converter with flying capacitor | |
| EP2517345B1 (en) | Groundable dc/dc converter | |
| CN115224928A (en) | Charging device | |
| JP6432832B2 (en) | Power converter | |
| JP2013074763A (en) | Power conversion device and control method thereof | |
| JP5102691B2 (en) | Power conversion device, discharge lamp lighting device using the same, and vehicle headlamp device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |