WO2023213292A1

WO2023213292A1 - Combined control voltage converter, control method, power supply, and new energy vehicle

Info

Publication number: WO2023213292A1
Application number: PCT/CN2023/092230
Authority: WO
Inventors: 王超
Original assignee: 长春捷翼汽车科技股份有限公司
Priority date: 2022-05-06
Filing date: 2023-05-05
Publication date: 2023-11-09
Also published as: CN114744875A

Abstract

Provided are a combined control voltage converter, a control method, a power supply, and a new energy vehicle. The converter comprises: a first switching tube, a second switching tube, a third switching tube which is in complementary conduction with the first switching tube, a fourth switching tube which is in complementary conduction with the second switching tube, an energy storage inductor, an energy storage capacitor, and a control unit. The control unit is used for acquiring an output voltage of an output port, comparing the output voltage with a reference voltage, and turning on/off the first switching tube or the second switching tube, so as to boost or buck the output voltage of the output port. In addition, in this solution, a small number of devices are used, and no large high-voltage diode is arranged in an integrated circuit, so that the size and the manufacturing cost of the voltage converter are reduced.

Description

A combined control voltage converter, control method, power supply and new energy vehicle

Related applications

This application claims priority to the Chinese invention patent application with application number 202210486689.8 submitted on May 6, 2022, and cites the entire disclosure of the above patent application as part of this application.

Technical field

This application relates to the technical field of adjustable DC power supply, especially a combined control voltage converter, control method, power supply and new energy vehicle.

Background technique

The power supply is an important part of the DC charging pile (DC Wallbox). Normally, the power supply is not only required to have high efficiency, small size, high power, etc., it is also required to have good dynamic performance and provide a wide output voltage with an adjustable range. ability. When the adjustable range of the input voltage is limited and the output voltage is required to be wide and adjustable, the output voltage will be required to both step up and step down.

Buck and Boost converters are the two simplest structures among buck and boost converters respectively. When these two circuits are combined, there are often more diodes and capacitors in the circuit structure, resulting in a larger circuit size. Moreover, the cost of high-voltage diodes is relatively high and cannot meet product requirements.

Therefore, there is a need for a circuit that can solve the problems in the prior art that the voltage converter has a single function, the traditional buck-boost structure is too expensive, and the circuit structure and control method are complex.

Contents of the invention

In view of the above-mentioned problems of the existing technology, the purpose of this article is to provide a combined control voltage converter, control method, power supply and new energy vehicle to solve the problem of the single function of the voltage converter and the traditional buck-boost structure in the existing technology. The cost is too high and the circuit structure and control methods are complex.

In order to solve the above technical problems, the specific technical solutions of this article are as follows.

The embodiment of the first aspect of the present application provides a combined control voltage converter, including: a buck-boost circuit, the buck-boost circuit is provided between an input port and an output port; the buck-boost circuit includes a first switch tube, a second switch tube, a third switch tube that is in complementary conduction with the first switch tube, a fourth switch tube that is in complementary conduction with the second switch tube, an energy storage inductor, an energy storage capacitor and a control unit; The drain of the first switch tube and the input port The anode of the switch is connected to the anode, the source of the first switch is connected to the drain of the third switch, the source of the third switch is connected to the cathode of the input port; one end of the energy storage inductor The drain of the third switch is connected, the other end is connected to the drain of the second switch, the source of the second switch is connected to the source of the third switch; The drains of the four switching tubes are connected to the drain of the second switching tube, and the source of the fourth switching tube is connected to one end of the energy storage capacitor; the control unit is respectively connected to the input port, the The gates of the first switch tube, the second switch tube, the third switch tube and the fourth switch tube are connected.

An embodiment of the second aspect of the present application provides a control method for the combined control voltage converter according to any one of the above, including: when receiving an instruction to make the output voltage of the output port lower than the input voltage of the input port, determining In the current voltage range where the output voltage is located, if the output voltage is lower than the first threshold, the first switch is controlled to be turned on/off periodically, and the second switch is controlled to be continuously turned off to reduce the output voltage. ; When receiving an instruction to make the output voltage higher than the input voltage, determine the voltage interval in which the current output voltage is located, and if the output voltage is higher than the second threshold, control the second switching tube cycle The first switch tube is turned on/off to control the conduction of the first switch tube to increase the output voltage; wherein, the on/off period of the first switch tube is determined according to the voltage loop signal, and the degree of reduction is determined according to the voltage loop signal. The duty cycle of the voltage loop signal is determined; the on/off period of the second switch tube is determined based on the voltage loop signal, and the degree of improvement is determined based on the duty cycle of the voltage loop signal.

A third embodiment of the present application provides a power supply provided with any of the combined control voltage converters described above.

An embodiment of the fourth aspect of the present application provides a new energy vehicle, which is provided with the power supply.

Using the above technical solution, it is possible to set up a buck-boost circuit between the input port and the output port of the power supply. The buck-boost circuit includes a first switch tube, a second switch tube, and a third switch that is in complementary conduction with the first switch tube. tube, a fourth switch tube that is complementary to the second switch tube, an energy storage inductor, an energy storage capacitor and a control unit. The control unit obtains the voltage of the output port and compares it with the voltage of the input port, thereby controlling the first switch tube, The second switching tube, the third switching tube and the fourth switching tube are turned on, off or periodically turned on and off to realize boosting or reducing the output voltage of the output port. In addition, this solution uses fewer devices and does not install large high-voltage diodes in the integrated circuit, which reduces the volume and manufacturing cost of the voltage converter.

In order to make the above and other objects, features and advantages of this article more obvious and understandable, preferred embodiments are cited below and described in detail with the accompanying drawings.

Description of the drawings

In order to more clearly explain the embodiments or the technical solutions in the prior art herein, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below.

Figure 1 shows a schematic diagram of a circuit of a combined control voltage converter according to an embodiment of this article.

Figure 2 shows a schematic diagram of the control unit in the embodiment of this article.

Figure 3 shows a detailed schematic diagram of the control unit of the embodiment of this article.

Figure 4 shows the circuit diagram of the control unit of the embodiment of this article.

Figure 5 shows a schematic diagram of the isolation module according to the embodiment of this article.

Figure 6 shows a schematic diagram of a control method for a combined control voltage converter according to the embodiment of this article.

Figure 7 shows a schematic diagram of the buffering method of a control method for a combined control voltage converter according to the embodiment of this article.

Detailed ways

The technical solutions in the embodiments of this article will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this article.

The embodiment of the first aspect of the present application provides a circuit for a combined control voltage converter as shown in FIG. 1 , including: a buck-boost circuit 12 , and the buck-boost circuit 12 is provided between the input port 11 and the output port 13 . The voltage-boosting and bucking circuit 12 includes a first switch tube 201, a second switch tube 202, a third switch tube 203 that is in complementary conduction with the first switch tube 201, a fourth switch tube 204 that is in complementary conduction with the second switch tube 202, Energy storage inductor 15, energy storage capacitor 16 and control unit 14. The drain of the first switch 201 is connected to the anode of the input port 11 , the source of the first switch 201 is connected to the drain of the third switch 203 , and the source of the third switch 203 is connected to the cathode of the input port 11 . One end of the energy storage inductor 15 is connected to the drain of the third switch 203 , the other end is connected to the drain of the second switch 202 , and the source of the second switch 202 is connected to the source of the third switch 203 . The drain of the fourth switch 204 is connected to the drain of the second switch 202 , and the source of the fourth switch 204 is connected to one end of the energy storage capacitor 16 . The control unit 14 is connected to the input port 11 and the gates of the first switch tube 201 , the second switch tube 202 , the third switch tube 203 and the fourth switch tube 204 respectively.

Using the above technical solution, the voltage-boost and buck circuit 12 is provided between the input port 11 and the output port 13 of the power supply. The voltage-boost and buck circuit 12 includes a first switch tube 201, a second switch tube 202, and a first switch tube 201. The third switching tube 203 which is in complementary conduction, the fourth switching tube 204 which is in complementary conduction with the second switching tube 202 , the energy storage inductor 15 , the energy storage capacitor 16 and the control unit 14 obtain the voltage of the output port 13 through the control unit 14 Compare it with the voltage of the input port 11, and then control the first switching tube 201, the second switching tube 202, the third switching tube 203 and the fourth switching tube 204 to be turned on, off or periodically turned on and off to achieve the output Boost or step down the output voltage of port 13. In addition, this solution uses fewer devices and is not included in the integrated circuit Setting up a larger high-voltage diode reduces the size and manufacturing cost of the voltage converter.

As an embodiment of this article, when the output voltage of the output port 13 is higher than the first threshold value of the input voltage of the input port 11 and lower than the second threshold value of the input voltage of the input port 11 , the control unit 14 controls the third The first switch tube 201 and the second switch tube 202 are turned on/off synchronously.

When the output voltage of the output port 13 is lower than the first threshold value of the input voltage of the input port 11 , the control unit 14 controls the second switch tube 202 to turn off, and controls the first switch tube 201 to turn on/off periodically.

When the output voltage of the output port 13 is higher than the second threshold value of the input voltage of the input port 11 , the control unit 14 controls the first switch tube 201 to be turned on and the second switch tube 202 to be turned on/off periodically.

It should be noted that the first threshold value in this article may be 90%, and the second threshold value may be 110%.

When the voltage converter is working, the output voltage may be a step-up or a step-down relative to the input voltage. When switching between the step-up or step-down, the on/off state of different switching tubes is quickly switched, which will cause the output Drastic changes in voltage cause fluctuations, which is unacceptable for the power supply and new energy vehicle fields that require high voltage stability. Therefore, in this article, when controlling the voltage converter, in order to avoid the above situation, a buffering method is set up. When the output voltage has a larger boost compared to the input voltage, or the output voltage has a larger boost compared to the input voltage, When the voltage reduction is large, the output voltage is higher than the second threshold or the output voltage is lower than the first threshold, time-sharing modulation can be used. When the output voltage does not significantly increase or decrease relative to the input voltage, and the output voltage is higher than the first threshold and lower than the second threshold, pulse width modulation of simultaneous on and simultaneous off can be used. The following details the time-sharing modulation and pulse width modulation of simultaneous on and off.

When determining the output voltage that needs to be outputted, the first switching tube 201 needs to be periodically turned on/off. For convenience of explanation, the periodic turning on/off is called pulse width adjustment control. Because the first switch tube 201 and the third switch tube 203 are in complementary conduction, that is, when the first switch tube 201 is on, the third switch tube 203 is off, so the third switch tube 203 is also under pulse width adjustment control. At this time, the second switch tube 202 is always turned off. Because the second switch tube 202 and the fourth switch tube 204 are in complementary conduction, the fourth switch tube 204 is always turned on. Then when the first switch tube 201 is turned on, the input Part of the voltage is input to the energy storage inductor 15, and part of it is input to the output port 13 through the fourth switch 204. Obviously, the output port 13 cannot obtain the entire input voltage, so the output voltage is a step-down relative to the input voltage. When the first switch tube 201 is turned off, the energy storage inductor 15 is equivalent to a power supply and inputs voltage to the output port 13, so that when the first switch tube 201 is turned off, the output port 13 can still output voltage. However, according to the circuit principle, the voltage of the energy storage inductor 15 cannot be greater than the voltage of the input port 11, so the input voltage obtained by the output port 13 is also lower than the input voltage of the input port 11. Therefore, through the above process, it is realized that when the first switch tube 201 is turned on/off, the output port 13 will output a voltage that is reduced relative to the input voltage.

In this article, "*" is the multiplication operator symbol.

Among them, the relationship between the output voltage and the input voltage is consistent with Ui=D1*Uo, D1 is the duty cycle of the first switch tube 201, Ui is the input voltage, and Uo is the output voltage. Therefore, by adjusting the turn-on or turn-off period of the first switch 201, the output voltage can be adjusted.

When determining the output voltage that needs to be boosted, the second switching transistor 202 needs to be periodically turned on/off. For convenience of explanation, the periodic turning on/off is called pulse width adjustment control. Because the second switch transistor 202 and the fourth switch transistor 204 are in complementary conduction, that is, when the second switch transistor 202 is on, the fourth switch transistor 204 is off, so the fourth switch transistor 204 is also under pulse width adjustment control. At this time, the first switch tube 201 is always on. Because the first switch tube 201 and the third switch tube 203 are in complementary conduction, the third switch tube 203 is always off. Then when the second switch tube 202 is on, the input voltage It is input to the energy storage inductor 15, so when the second switch tube 202 is turned on, the output voltage at the output port 13 is zero. When the second switch 202 is turned off, the energy storage inductor 15 is equivalent to the power supply, inputting voltage to the output port 13, and the energy storage capacitor 16 also stores energy and discharges, so the output voltage of the output port 13 is equivalent to the energy storage inductor 15 and The voltage of the energy storage capacitor 16 acts together, so the input voltage obtained by the output port 13 is also improved relative to the input voltage of the input port 11. Therefore, through the above process, it is realized that the output port 13 can output a voltage greater than the input port 11 when the second switch 202 is turned on/off.

Among them, the relationship between the output voltage and the input voltage is consistent with Ui=Uo/(1-D2), D2 is the duty cycle of the second switch tube 202, Ui is the input voltage, and Uo is the output voltage. Therefore, by adjusting the turn-on and turn-off periods of the second switch 202, the output voltage can be adjusted.

Through the above process, it can be seen that during the voltage boosting or bucking process, the first switching transistor 201 or the second switching transistor 202 needs to be controlled by pulse width adjustment. This sudden change in the pulse width adjustment control may cause the output port 13 to The output voltage of the switch suddenly changes, so that the output port 13 cannot provide a normal voltage, so it is necessary to use the following method to control the first switch transistor 201 and the second switch transistor 202 to further reduce the sudden change.

When switching, the first switching tube 201 and the second switching tube 202 can be controlled by pulse width adjustment at the same time. When the first switching tube 201 and the second switching tube 202 are turned on, the energy storage inductor 15 is charged, and the output voltage is zero. Then the first switching tube 201 and the second switching tube 202 are turned off. At this time, the energy storage inductor 15 discharges the output port 13. According to the volt-second balance of the inductor charging and discharging, the relationship formula can be obtained as Ui=D*Uo /(1-D), D is the duty cycle when the first switch tube 201 and the second switch tube 202 are turned on at the same time, Ui is the input voltage, Uo is the output voltage, it can be deduced that when D>0.5, the voltage boost is achieved ; When D<0.5, voltage reduction is achieved. This control method does not have the advantage of a wide adjustment range of time-sharing control duty cycle, but its switching between voltage increase and decrease is very smooth.

As an embodiment of this article, the above-mentioned on/off switching of the first switching tube 201, the second switching tube 202, the third switching tube 203 and the fourth switching tube 204 is realized through the control unit 14, and the control unit 14 obtains the output voltage and the input voltage to control the first switching tube 201 , the second switching tube 202 , the third switching tube 203 and the fourth switching tube 204 . In order for those skilled in the art to implement this solution more clearly, this article will describe the specific circuit principles and topology of the control unit 14 in detail. In the control unit 14, the specific functions of some modules have been explained. The technical knowledge in the art can be based on the technology of this article. Enlightenment, equivalent replacement of conventional technology or existing technology, but they should all fall within the protection scope of this article. As for conventional technology, this article will not elaborate here.

As shown in the schematic diagram of the control unit 14 in FIG. 2 , the control unit 14 includes a sampling comparison module 21 and a driving module 22 . The sampling comparison module 21 is used to collect the reference voltage and the output voltage of the output port 13 to generate a voltage loop signal, and is used to collect the reference voltage and the input voltage of the input port 11 and generate a boost signal or a buck signal. The driving module 22 is used to receive a voltage loop signal, a boost signal or a buck signal, and generate a driving signal to drive the first switching tube 201, the second switching tube 202, the third switching tube 203 and the fourth switching tube 204 to turn on or off. Deadline.

It should be noted that the sampling comparison module 21 can receive a reference voltage, an input voltage and an output voltage. Through comparison, the sampling comparison module 21 can output the voltage loop signal and the boost signal at the same time, or output the voltage loop signal and the buck signal at the same time.

The driving module 22 receives one of the boost signal and the buck signal and the voltage loop signal respectively, and drives the first switching tube 201, the second switching tube 202, the third switching tube 203 and the fourth switching tube 204 to be turned on or off to achieve Reduce or increase the output voltage.

As shown in FIG. 3 , as an embodiment of this article, the driving module 22 includes a first waveform comparison component 34 and a second waveform comparison component 35 .

The first waveform comparison component 34 is used to compare the voltage loop signal and the boost signal to drive the first switching tube 201 and the third switching tube 203;

The second waveform comparison component 35 is used to compare the voltage loop signal and the buck signal to drive the second switch tube 202 and the fourth switch tube 204 .

It should be noted that the voltage loop signal is used to control the duty cycle of the pulse width adjustment control of the first switching tube 201 or the second switching tube 202, and the boost signal is used to send to the first switching tube 201 and the third switching tube 203 to To realize the step-up function of the output voltage, the buck signal is used to send to the second switch transistor 202 and the fourth switch transistor 204 to realize the step-down function of the output voltage.

As an embodiment herein, the sample comparison module 21 includes a first category comparison component 31 . The first type comparison component 31 is used to collect the reference voltage and the output voltage to generate a voltage loop signal.

As an embodiment herein, the sample comparison module 21 includes a second category comparison component 32 . The second type comparison component 32 is used to collect the reference voltage and the amplified input voltage, and generate a boost signal. It should be noted that the amplified input voltage may be, for example, a larger voltage than a conventional input voltage, which The voltage is the input voltage that has not been amplified or reduced. For example, it can be a voltage range or a fixed value. In the case of a fixed value, when the input voltage is higher than the value, the input voltage is determined to be the amplified input voltage. If it is a voltage value interval, when the input voltage is higher than the maximum value of the voltage value interval, the input voltage is determined to be an amplified input voltage.

As an embodiment herein, the sample comparison module 21 includes a third category comparison component 33 . The third category comparison component 33 is used to collect the reference voltage and the reduced input voltage, and generate a buck signal. It should be noted that the reduced input voltage may be, for example, a voltage smaller than the conventional input voltage.

As an embodiment of this article, as shown in the detailed schematic diagram of the control unit 14 in FIG. 3 , the sampling comparison module 21 includes a first category comparison component 31 , a second category comparison component 32 , and a third category comparison component 33 . The driving module 22 includes a first waveform comparison component 34 and a second waveform comparison component 35 . The first type comparison component 31 is configured to receive the output voltage and the reference voltage of the output port 13 and send voltage loop signals to the first waveform comparison component 34 and the second waveform comparison component 35 respectively. The second type comparison component 32 is configured to receive the reference voltage and the amplified input voltage, and send a boost signal to the first waveform comparison component 34 . The third type comparison component 33 is configured to receive the reference voltage and the reduced input voltage, and send a buck signal to the second waveform comparison component 35 . The first waveform comparison component 34 is used to drive the first switching tube 201 and the third switching tube 203 . The second waveform comparison component 35 is used to drive the second switching transistor 202 and the fourth switching transistor 204 .

In this article, the reference voltage can be adjusted according to the input voltage, which is not limited in this article.

In order to satisfy the voltage difference between the voltage loop signal and the buck when the output voltage is lower than the input voltage, when the circuit is working abnormally, the output terminal and the input terminal of the first type operator 401 and the third type operator 403 can be Set the PI adjustment combination. In this way, the duty cycle of the second switching transistor 202 can be gradually increased or decreased, and at this time, the duty cycle of the first switching transistor 201 is changed synchronously to ensure the stability of the output voltage. The specific circuit is shown in Figure 4.

As shown in the circuit diagram of the control unit 14 shown in Figure 4, the first category comparison component 31 (shown in Figure 3) includes a first category operator 401, a first resistor 101, a second resistor 102, a third resistor 103 and a first capacitor 301 . One end of the first resistor 101 is connected to the output voltage, and the other end is connected to the inverting input end of the first type operator 401 . One end of the second resistor 102 is connected to the reference voltage, and the other end is connected to the positive input end of the first type operator 401 . The output terminal of the first type operator 401 outputs a voltage loop signal and is connected to one end of the first capacitor 301, The other end of the first capacitor 301 is connected to one end of the third resistor 103, and the other end of the third resistor 103 is connected to the inverting input end.

In the above-mentioned first type operator 401, the third resistor 103 and the first capacitor 301 form a PI adjustment structure. The output end of the first type operator 401 can output a voltage loop signal to realize control of the first switch tube 201 (such as (shown in Figure 1) and the control of the second switch tube 202 (shown in Figure 1).

The second category comparison component 32 (shown in FIG. 3 ) includes a second category operator 402, a fourth resistor 104, a fifth resistor 105, a sixth resistor 106, a seventh resistor 107 and a second capacitor 302. One end of the fourth resistor 104 is connected to the amplified input voltage, and the other end is connected to the positive input end of the second type operator 402 . One end of the fifth resistor 105 is connected to the reference voltage, and the other end is connected to the inverting input end of the second type operator 402 . The output end of the second type operator 402 outputs a boost signal and is connected to one end of the sixth resistor 106. The other end of the sixth resistor 106 is connected to VCC. The power input end of the second type operator 402 is connected to VCC. One end of the seventh resistor 107 is connected to one end of the sixth resistor 106, the other end of the seventh resistor 107 is connected to one end of the second capacitor 302, and the other end of the second capacitor 302 is connected to ground.

In the above-mentioned second type operator 402, the seventh resistor 107 and the second capacitor 302 form a buffer. The seventh resistor 107 can reduce the input voltage to implement a protection circuit. The second capacitor 302 can output the second type operator 402. The waveform is filtered, and the output end of the second category operator 402 can output a boost signal to control the first switch tube 201 and the third switch tube 203 .

The third category comparison component 33 (shown in FIG. 3 ) includes a third category operator 403 , an eighth resistor 108 , a ninth resistor 109 , a tenth resistor 110 and a third capacitor 303 . One end of the eighth resistor 108 is connected to the reduced input voltage, and the other end is connected to the positive input end of the third category operator 403 . One end of the ninth resistor 109 is connected to the reference voltage, and the other end is connected to the inverting input end of the third category operator 403 . The output end of the third category operator 403 outputs a buck signal and is connected to one end of the third capacitor 303. The other end of the third capacitor 303 is connected to one end of the tenth resistor 110. The other end of the tenth resistor 110 is connected to the third category The inverting input terminal of the operator 403 is connected.

In the above-mentioned third type operator 403, the tenth resistor 110 and the third capacitor 303 form a PI adjustment structure. The output terminal of the third type operator 403 can output a buck signal to control the second switching tube 202 and the fourth switching tube 204 .

The first waveform comparison component 34 (shown in FIG. 3 ) includes an eleventh resistor 111 , a twelfth resistor 112 , a thirteenth resistor 113 , a first waveform comparator 404 , a first driver 501 , a third driver 503 and a third resistor 111 . An inverter 601. One end of the eleventh resistor 111 receives the voltage loop signal and the boost signal, and the other end is connected to the forward input end of the first waveform comparator 404 . One end of the twelfth resistor 112 receives the sawtooth wave, and the other end is connected to the first waveform. The inverting input of comparator 404 is connected. The forward voltage input terminal of the first waveform comparator 404 is connected to VCC through the thirteenth resistor 113, and the reverse voltage input terminal of the first waveform comparator 404 is connected to the second waveform comparator 405 through a synchronizer. The output terminal of the first waveform comparator 404 is connected to one terminal of the first driver 501 and one terminal of the first inverter 601 respectively. The first inverter 601 is connected to one end of the third driver 503 . The other end of the first driver 501 is connected to the gate of the first switch tube 201 . The other end of the third driver 503 is connected to the gate of the third switch tube 203 .

In this paper, in order to achieve smooth switching when switching the switch tube on or off, an energy storage inductor 15 (as shown in Figure 1) and an energy storage resistor are used for buffering. When switching, the energy storage capacitor 16 (as shown in Figure 1) is charged and discharged, and the voltage intersecting with the sawtooth wave gradually changes, and the duty cycle of the first switch tube 201 gradually increases or decreases. At this time, the second switch tube 202 The duty cycle is still adjusted to ensure the stability of the output voltage.

The second waveform comparison component 35 (shown in FIG. 3 ) includes a fourteenth resistor 114 , a fifteenth resistor 115 , a sixteenth resistor 116 , a second waveform comparator 405 , a second driver 502 , a fourth driver 504 and a Two inverters 602. One end of the fourteenth resistor 114 receives the voltage loop signal and the buck signal respectively, and the other end is connected to the forward input end of the second waveform comparator 405 . One end of the fifteenth resistor 115 receives the sawtooth wave, and the other end is connected to the inverting input end of the second waveform comparator 405 . The forward voltage input terminal of the second waveform comparator 405 is connected to VCC, and the reverse voltage input terminal of the second waveform comparator 405 is connected to the first waveform comparison component 34 through a synchronizer. The output terminal of the second waveform comparator 405 is connected to one terminal of the sixteenth resistor 116, and the other terminal of the sixteenth resistor 116 is connected to VCC, one terminal of the second driver 502 and one terminal of the second inverter 602 respectively. The second inverter 602 is connected to one end of the fourth driver 504 . The other end of the second driver 502 is connected to the second switch tube 202 . The other end of the fourth driver 504 is connected to the fourth switch tube 204 .

It should be noted that the synchronizer 701 realizes voltage synchronization of the reverse voltage input terminals of the first waveform comparator 404 and the second waveform comparator 405, that is, maintains GND synchronization of the first waveform comparator 404 and the second waveform comparator 405. In this way, the comparison bases of the two waveform comparators can be made consistent, and the switching tube can be turned on or off better.

Through the above-mentioned first inverter 601 and second inverter 602, complementary conduction is achieved, and the corresponding potential is: when the first waveform comparator 404 sends a high level, the first switch tube 201 is turned on, and After the high level passes through the first inverter, a low level is generated, and then the low level is sent to the third switch transistor 203, causing the third switch transistor 203 to turn off. Therefore, complementary conduction of the first switching transistor 201 and the third switching transistor 203 can be achieved through the first inverter.

The complementary conduction of the second switch transistor 202 and the fourth switch transistor 204 is also the above-mentioned process. In order to reduce the length, the details will not be described in the embodiment of this article.

Further, as shown in the schematic diagram of the isolation module 23 in Figure 5, as an embodiment of this article, the sampling comparison module An isolation module 23 is also provided between the block 21 and the drive module 22 . The isolation module 23 is used to prevent the output voltage from flowing back to the input port 11 . The isolation module 23 includes a first isolation component.

The first isolation component includes a first isolator 901, a first diode 801, a second diode 802, a seventeenth resistor 117 and an eighteenth resistor 118. One end of the first isolator 901 is connected to the output end of the first type operator 401 , and the other end is connected to the anode of the first diode 801 . The cathode of the first diode 801 is connected to one end of the seventeenth resistor 117 . The other end of the seventeenth resistor 117 is connected to one end of the eighteenth resistor 118 . The other end of the eighteenth resistor 118 is connected to ground. The anode of the second diode 802 is connected to the other end of the seventh resistor 107 . The cathode of the second diode 802 is connected to one end of the twelfth resistor 112 . The isolation module 23 may also comprise a second isolation component, for example.

The second isolation component includes a second isolator 902, a third diode 803, a fourth diode 804, a nineteenth resistor 119 and a twentieth resistor 120. One end of the second isolator 902 is connected to the output end of the first type operator 401 , and the other end is connected to the anode of the third diode 803 . The cathode of the third diode 803 is connected to one end of the nineteenth resistor 119 . The other end of the nineteenth resistor 119 is connected to one end of the twentieth resistor 120 . The other end of the twentieth resistor 120 is connected to ground. The cathode of the fourth diode 804 is connected to one end of the third capacitor 303 . The anode of the fourth diode 804 is connected to one end of the fourteenth resistor 114 .

In order to prevent the output voltage from flowing back during voltage reduction and affecting the on/off cycle of the switching tube, it is necessary to add a circuit with isolation function on the signal side of the voltage loop to improve the stability of the circuit.

The embodiment of the second aspect of the present application is shown in Figure 6, which provides a control method for combined control of a voltage converter, including:

Step 601: When receiving an instruction to make the output voltage of the output port 13 lower than the input voltage of the input port 11, determine the voltage range in which the current output voltage is located. If the output voltage is lower than the first threshold, control the first switch 201 The second switching tube 202 is controlled to be turned off by periodic on/off, so that the output voltage is reduced, where the degree of reduction is determined according to the on/off cycle of the first switching tube 201 .

Step 602: When receiving an instruction to make the output voltage of the output port 13 higher than the input voltage of the input port 11, determine the voltage range in which the current output voltage is located. If the output voltage is higher than the second threshold, control the second switch 202. Periodically turning on/off controls the first switching transistor 201 to turn on, so as to increase the output voltage, where the degree of improvement is determined according to the on/off cycle of the second switching transistor 202 .

The on/off period of the first switching tube is determined according to the voltage loop signal, and the degree of reduction is determined according to the duty cycle of the voltage loop signal. The on/off period of the second switch tube is determined according to the voltage loop signal, and the degree of improvement is determined according to the duty cycle of the voltage loop signal.

Specifically speaking, the voltage loop signal is similar to a square wave signal. When the frequency of the square wave signal is certain, it can be changed by By changing the duty cycle, that is, taking 0-2 seconds as a cycle, the high level can be maintained for 1.5 seconds, the low level can be maintained for 0.5 seconds, etc. within 2 seconds. In this way, the output voltage can be changed. Specifically, the maximum value of the output voltage is 100V. When the duty cycle of the square wave signal is 100%, a voltage of 100V can be output. When the duty cycle of the square wave signal is 50% , can output 50V voltage, etc.

In this article, the total output voltage is 30V, then the duty cycle corresponding to the output of 2-22V is 2/30-22/30, that is, the duty cycle is about 7%--73%.

Through the above control method, the output voltage can be obtained and the voltage range in which the output voltage is located can be determined. When it is determined that voltage reduction is required and the voltage range in which the output voltage is located is lower than the first threshold, the output voltage can be reduced through the cooperation of the first switch tube 201 and the second switch tube 202 . It should be noted that when it is determined that the voltage interval in which the output voltage is located is lower than the first threshold, it is determined that the output voltage is lower than the first threshold. Furthermore, when it is determined that voltage boosting is required and the voltage range in which the output voltage is located is higher than the second threshold, the output voltage can be increased through the cooperation of the first switching transistor 201 and the second switching transistor 202 . It should be noted that when it is determined that the voltage interval in which the output voltage is located is higher than the second threshold, it is determined that the output voltage is higher than the first threshold. Using the control method in this article, the output voltage step-up and step-down effect is improved, which meets the needs of duty cycle adjustment.

It should be noted that the degree of reduction or improvement can be determined according to the formula. When voltage reduction is required, that is, when the output voltage is lower than the input voltage, the formula Ui=D1*Uo is used, where D1 is the occupancy of the first switch tube 201. The output voltage can be adjusted by adjusting the duty ratio of the first switching tube 201 .

When boosting is required, that is, when the output voltage is greater than the input voltage, the formula Ui=Uo/(1-D2) is used, where D2 is the duty cycle of the second switching tube 202. By adjusting the duty cycle of the second switching tube 202 Ratio can adjust the output voltage.

As shown in Figure 7, a schematic diagram of a buffering method of a combined control voltage converter control method, as an embodiment of this article, determining the voltage interval in which the current output voltage is located further includes:

Step 701. If the output voltage is higher than the first threshold and lower than the second threshold, the first switch 201 and the second switch 202 are periodically turned on/off synchronously to increase/lower the output voltage; wherein, the output The degree of voltage increase/decrease is determined based on the periodicity of the synchronous on/off of the second switch transistor 202, and the degree of output voltage increase/decrease is determined based on the duty cycle of the voltage loop signal.

It should be noted that when the output voltage is suddenly switched from the boost state to the buck state, the duty cycle of different switching tubes changes, which will cause drastic fluctuations in the output voltage, which is very important for new energy sources that integrate electronic components. This is unacceptable for cars, so it is necessary to propose a buffering method to reduce the fluctuation of the output voltage when the voltage is switched.

This article uses simultaneous on and off control. When the voltage needs to be boosted from below the first threshold to above the second threshold, It is necessary to make the first switching tube 201 and the second switching tube 202 switch on and off at the same time, so that the energy storage inductor 15 in the converter can store or discharge energy, and the sudden change of the output voltage can be alleviated through the buffering of the LC circuit.

As an embodiment of this article, the degree of increase/decrease of the output voltage is determined according to the duty cycle of the voltage loop signal, which further includes: if the duty cycle of the voltage loop signal is less than fifty percent, the output voltage is reduced, and if the duty cycle of the voltage loop signal When the duty cycle of the signal is greater than 50%, the output voltage increases.

It should be noted that the specific conversion method can be determined according to the formula Ui=D*Uo/(1-D), where D is the common duty cycle of the first switching transistor 201 and the second switching transistor 202. Obviously, when D>0.5, the voltage is increased; when D<0.5, the voltage is reduced.

A third embodiment of the present application provides a power supply provided with the above-mentioned combined control voltage converter.

An embodiment of the fourth aspect of the present application provides a new energy vehicle, which is equipped with the above-mentioned power supply.

Those of ordinary skill in the art can appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented with electronic hardware, computer software, or a combination of both. In order to clearly illustrate the relationship between hardware and software Interchangeability, in the above description, the composition and steps of each example have been generally described according to functions.

A unit described as a separate component may or may not be physically separate. A component shown as a unit may or may not be a physical unit, that is, it may be located in one place, or it may be distributed to multiple network units.

Claims

A combined control voltage converter, characterized by including:

A buck-boost circuit, the buck-boost circuit is located between the input port and the output port;

The step-up and step-down circuit includes a first switch tube, a second switch tube, a third switch tube that is in complementary conduction with the first switch tube, a fourth switch tube that is in complementary conduction with the second switch tube, and a storage device. Energy inductor, energy storage capacitor and control unit;

The drain of the first switch is connected to the anode of the input port, the source of the first switch is connected to the drain of the third switch, and the source of the third switch is connected to the Connect the negative pole of the above input port;

One end of the energy storage inductor is connected to the drain of the third switch, the other end is connected to the drain of the second switch, and the source of the second switch is connected to the drain of the third switch. The sources are connected;

The drain of the fourth switch is connected to the drain of the second switch, and the source of the fourth switch is connected to one end of the energy storage capacitor;

The control unit is respectively connected to the input port, the first switch tube, the second switch tube, the third switch tube and the gate of the fourth switch tube.
The combined control voltage converter according to claim 1, wherein the control unit is configured as:

When the output voltage of the output port is lower than the first threshold value of the input voltage of the input port, control the second switch tube to turn off, and control the first switch tube to periodically turn on/off;

When the output voltage of the output port is higher than the second threshold value of the input voltage of the input port, the first switch tube is controlled to be turned on, and the second switch tube is controlled to be turned on/off periodically;

When the output voltage of the output port is higher than the first threshold value of the input voltage of the input port and lower than the second threshold value of the input voltage of the input port, the first switch tube and the The second switch tube is turned on/off synchronously.
The combined control voltage converter according to claim 2, wherein the control unit includes a sampling comparison module and a driving module;

The sampling comparison module is used to collect the reference voltage and the output voltage and generate a voltage loop signal, and is used to collect the reference voltage and the input voltage and generate a boost signal or a buck signal;

The driving module is used to receive the voltage loop signal, the boost signal or the buck signal and generate a driving signal to drive the first switching tube, the second switching tube and the third switching tube. and the turn-on/off of the fourth switch tube.
The combined control voltage converter according to claim 3, wherein the driving module includes a first waveform comparison component and a second waveform comparison component;

The first waveform comparison component is used to compare the voltage loop signal and the boost signal to drive the first switch tube and the third switch tube;

The second waveform comparison component is used to compare the voltage loop signal and the buck signal to drive the second switch tube and the fourth switch tube.
The combined control voltage converter according to claim 4, wherein the sampling comparison module includes a first category comparison component;

The first type comparison component is used to collect the reference voltage and the output voltage, and generate the voltage loop signal.
The combined control voltage converter according to claim 5, wherein the sampling comparison module includes a second category comparison component;

The second category comparison component is used to collect the reference voltage and the amplified input voltage, and generate the boost signal.
The combined control voltage converter according to claim 6, wherein the sampling comparison module includes a third category comparison component;

The third category comparison component is used to collect the reference voltage and the reduced input voltage, and generate the buck signal.
The combined control voltage converter according to claim 7, wherein the first category comparison component includes a first category operator, a first resistor, a second resistor, a third resistor and a first capacitor;

One end of the first resistor is connected to the output voltage, and the other end is connected to the reverse input end of the first category operator;

One end of the second resistor is connected to the reference voltage, and the other end is connected to the forward input end of the first category operator;

The output end of the first type operator outputs the voltage loop signal and is connected to one end of the first capacitor. The other end of the first capacitor is connected to one end of the third resistor. The third The other end of the resistor is connected to the inverting input terminal.
The combined control voltage converter according to claim 8, wherein the second category comparison component includes a second category operator, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor and a second capacitor. ;

One end of the fourth resistor is connected to the amplified input voltage, and the other end is connected to the forward input end of the second category operator;

One end of the fifth resistor is connected to the reference voltage, and the other end is connected to the inverse direction of the second type operator. The input terminals are connected;

The output end of the second type operator outputs the boost signal and is connected to one end of the sixth resistor. The other end of the sixth resistor is connected to VCC. The power input end of the second type operator is connected to The VCC is connected;

One end of the seventh resistor is connected to one end of the sixth resistor, the other end of the seventh resistor is connected to one end of the second capacitor, and the other end of the second capacitor is connected to ground.
The combined control voltage converter according to claim 9, wherein the third category comparison component includes a third category operator, an eighth resistor, a ninth resistor, a tenth resistor and a third capacitor;

One end of the eighth resistor is connected to the reduced input voltage, and the other end is connected to the forward input end of the third category operator;

One end of the ninth resistor is connected to the reference voltage, and the other end is connected to the inverting input end of the third category operator;

The output terminal of the third type operator outputs the buck signal and is connected to one end of the third capacitor. The other end of the third capacitor is connected to one end of the tenth resistor. The tenth resistor The other end is connected to the inverting input end of the third category operator.
The combined control voltage converter according to claim 10, wherein the first waveform comparison component includes an eleventh resistor, a twelfth resistor, a thirteenth resistor, a first waveform comparator, a first driver, third driver and first inverter;

One end of the eleventh resistor receives the voltage loop signal and the boost signal, and the other end is connected to the forward input end of the first waveform comparator;

One end of the twelfth resistor receives the sawtooth wave, and the other end is connected to the reverse input end of the first waveform comparator;

The forward voltage input end of the first waveform comparator is connected to the VCC, and the reverse voltage input end of the first waveform comparator is connected to the second waveform comparison component through a synchronizer;

The output end of the first waveform comparator is respectively connected to one end of the first driver and one end of the first inverter;

The first inverter is connected to one end of the third driver;

The other end of the first driver is connected to the gate of the first switch tube;

The other end of the third driver is connected to the gate of the third switch tube.
The combined control voltage converter according to claim 11, wherein the second waveform comparison component includes a fourteenth resistor, a fifteenth resistor, a sixteenth resistor, a second waveform comparator, a second driver, fourth driver and second inverter;

One end of the fourteenth resistor receives the voltage loop signal and the buck signal respectively, and the other end is connected to the forward input end of the second waveform comparator;

One end of the fifteenth resistor receives the sawtooth wave, and the other end is connected to the reverse input end of the second waveform comparator;

The forward voltage input terminal of the second waveform comparator is connected to VCC, and the reverse voltage input terminal of the second waveform comparator is connected to the first waveform comparison component through a synchronizer;

The output end of the second waveform comparator is connected to one end of the sixteenth resistor, and the other end of the sixteenth resistor is connected to the VCC, one end of the second driver and the second inverter respectively. Connect one end of the device;

The second inverter is connected to one end of the fourth driver;

The other end of the second driver is connected to the second switch tube;

The other end of the fourth driver is connected to the fourth switch tube.
The combined control voltage converter according to claim 12, characterized in that:

An isolation module is also provided between the sampling comparison module and the driving module;

The isolation module is used to prevent the output voltage from flowing back to the input port.
The combined control voltage converter according to claim 13, wherein the isolation module includes a first isolation component for connecting the first type comparison component and the second type comparison component to the third type comparison component respectively. A waveform comparison component for isolation, the first isolation component specifically includes: a first isolator, a first diode, a second diode, a seventeenth resistor and an eighteenth resistor;

One end of the first isolator is connected to the output end of the first category operator, and the other end is connected to the anode of the first diode;

The cathode of the first diode is connected to one end of the seventeenth resistor;

The other end of the seventeenth resistor is connected to one end of the eighteenth resistor;

The other end of the eighteenth resistor is grounded;

The anode of the second diode is connected to the other end of the seventh resistor;

The cathode of the second diode is connected to one end of the eleventh resistor.
The combined control voltage converter according to claim 14, wherein the isolation module includes a second isolation component for connecting the second type comparison component and the third type comparison component to the third type comparison component respectively. Two waveform comparison components are isolated, and the second isolation component specifically includes: a second isolator, a third diode, a fourth diode, a nineteenth resistor and a twentieth resistor;

One end of the second isolator is connected to the output end of the first type operator, and the other end is connected to the third second isolator. The anode of the pole tube is connected;

The cathode of the third diode is connected to one end of the nineteenth resistor;

The other end of the nineteenth resistor is connected to one end of the twentieth resistor;

The other end of the twentieth resistor is grounded;

The cathode of the fourth diode is connected to one end of the third capacitor;

The anode of the fourth diode is connected to one end of the fourteenth resistor.
The control method of the combined control voltage converter according to any one of claims 1 to 15, characterized in that it includes:

When receiving an instruction to make the output voltage of the output port lower than the input voltage of the input port, determine the voltage range in which the current output voltage is located. If the output voltage is lower than the first threshold, control the periodicity of the first switch tube. On/off, control the second switch tube to continue to turn off to reduce the output voltage;

When receiving an instruction to make the output voltage higher than the input voltage, determine the voltage range in which the current output voltage is located. If the output voltage is higher than the second threshold, control the periodicity of the second switch tube. On/off, controlling the conduction of the first switch tube to increase the output voltage;

Wherein, the on/off period of the first switch tube is determined according to the voltage loop signal, and the degree of reduction is determined according to the duty cycle of the voltage loop signal;

The on/off period of the second switch tube is determined according to the voltage loop signal, and the degree of improvement is determined according to the duty cycle of the voltage loop signal.
The control method of a combined control voltage converter according to claim 16, wherein determining the voltage interval in which the current output voltage is located further includes:

If the output voltage is higher than the first threshold and lower than the second threshold, the first switching tube and the second switching tube are controlled to periodically turn on/off synchronously, so that the output Voltage boost/drop;

Wherein, the periodic synchronous on/off of the second switch tube is determined according to the voltage loop signal, and the degree of increase/decrease of the output voltage is determined according to the duty cycle of the voltage loop signal.
The control method of a combined control voltage converter according to claim 17, wherein the degree of increase/decrease of the output voltage is determined according to the duty cycle of the voltage loop signal, further comprising:

If the duty cycle of the voltage loop signal is less than 50%, the output voltage is reduced. If the duty cycle of the voltage loop signal is greater than 50%, the output voltage is increased.
A power supply, characterized in that the power supply is provided with the combined control voltage converter according to any one of claims 1-15.
A new energy vehicle, characterized in that the new energy vehicle is provided with a vehicle as claimed in claim 19 power supply.