Dead time determination method, charge drive circuit, device, equipment, and medium

Abstract

The present invention discloses a dead time determination method, a charging drive circuit, a device, an apparatus, and a medium, and the dead time determination method includes: acquiring an output current of a charging drive circuit; determining a load state of the charging drive circuit based on the output current of the charging drive circuit; acquiring an output voltage of the charging drive circuit; and determining a dead time of the charging drive circuit based on the output voltage and the load state of the charging drive circuit. The present invention determines the dead time of the charging drive circuit under different load states based on the output current and output voltage of the charging drive circuit, thereby allowing the charging device to output a stable voltage or current.

Description

[Technical Field]

[0001] This application claims priority to a Chinese patent application filed on August 26, 2021, bearing application number 202110988747.2 and entitled "Method for determining dead time, charging drive circuit, device, equipment and medium," the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to the field of power, and in particular to a dead time determination method, a charge drive circuit, a device, an apparatus and a medium. [Background technology]

[0003] This section is intended to provide a background or context for the claimed embodiments of the invention. Nothing herein is admitted as prior art for inclusion in this section.

[0004] With the development of new energy vehicles, rapid charging of new energy vehicles has become a new market need. When charging electric vehicles at conventional charging stations, a long charging time is usually required. In order to improve the charging efficiency of the power supply, the power elements in the bridge circuit need to operate in a soft switching state, so the dead time corresponding to the power elements needs to be reasonably adjusted.

[0005] In related art, fixed time control is generally used to control the dead time of a power element, but when controlling the dead time using this method in related art, the dead time in some operating regions is shorter than the actual soft switching time, resulting in insufficient soft switching and reducing the charging efficiency of the power supply. Summary of the Invention

[0006] An embodiment of the present invention provides a dead time determination method for determining the dead time of a charge drive circuit in real time, including: obtaining an output current of the charge drive circuit; determining a load state of the charge drive circuit based on the output current of the charge drive circuit; obtaining an output voltage of the charge drive circuit; and determining the dead time of the charge drive circuit based on the output voltage and the load state of the charge drive circuit.

[0007] Furthermore, the load state may be an idling state or a loaded state.

[0008] Furthermore, determining the dead time y1 during which the charge drive circuit is in an idle state includes first calculating the product of the proportionality coefficient k and the input voltage x, and then calculating the sum of the product and the bias constant b as the dead time y1 during which the charge drive circuit is in an idle state.

[0009] Furthermore, determining the dead time y when the charge drive circuit is in a load-applied state includes calculating the product of the ratio of the system clock frequency f to the operating frequency and a first coefficient, calculating the difference between the product and the dead time y1 when the charge drive circuit is in an idling state, and calculating the product of the difference and a second coefficient as the dead time y when the charge drive circuit is in a load-applied state.

[0010] Furthermore, determining the load state of the charging drive circuit based on the output current of the charging drive circuit includes determining the load state of the charging drive circuit as a loaded state if the output current of the charging drive circuit is greater than a first predetermined threshold, and determining the load state of the charging drive circuit as an idling state if the output current of the charging drive circuit is less than a second predetermined threshold.

[0011] Furthermore, the first predetermined threshold is greater than the second predetermined threshold.

[0012] In an embodiment of the present invention, a charging driving circuit is further provided to solve the technical problem that a power device in a conventional charging station adopts a dead time of a certain length, which results in a long charging time for charging an electric vehicle. The charging driving circuit includes a power supply module, a voltage collection module, a current collection module, a transistor driving circuit, a transistor switch circuit, and a microcontroller unit, wherein the power supply module is used to connect to a power supply device to provide a power supply voltage, the transistor switch circuit is connected to a load device and is used to supply power to the load device, and the transistor driving circuit is connected between the microcontroller unit and the transistor switch circuit, the voltage collecting module is connected to the output terminal of the transistor switch circuit and is used to collect the output voltage of the transistor switch circuit; the current collecting module is connected to the output terminal of the transistor switch circuit and is used to collect the output current of the transistor switch circuit; the microcontrol unit is connected to the voltage collecting module and the current collecting module respectively, and the microcontrol unit is arranged to determine a dead time of the charge driving circuit based on the output voltage of the transistor switch circuit and the load state of the charge driving circuit, and to generate a control signal for controlling the on / off of the transistor switch circuit based on the dead time.

[0013] Furthermore, the transistor driving circuit is realized by a first driving chip and a second driving chip, and the first driving chip and the second driving chip are dual-channel isolated gate drivers with dual input interfaces for driving a half-bridge circuit or a full-bridge circuit.

[0014] Furthermore, the model number of the chip adopted by the first driver chip and the second driver chip is UCC21520.

[0015] Further, the microcontrol unit includes an acquisition unit for acquiring the output voltage and output current of the charging drive circuit, a determination unit for determining the load state of the charging drive circuit based on the output current, and a calculation unit for calculating the dead time of the charging drive circuit based on the output voltage and the load state.

[0016] An embodiment of the present invention further provides a charging device to solve the technical problem that a power device in a conventional charging station adopts a dead time of a certain length, which results in a long charging time required to charge an electric vehicle, and the charging device includes the above-mentioned charging drive circuit.

[0017] An embodiment of the present invention further provides a computer device for solving the technical problem that power devices in conventional charging stations adopt a fixed dead time, resulting in a long charging time required to charge an electric vehicle. The computer device includes a memory, a processor, and a computer program stored in the memory and operable by the processor, and when the processor executes the computer program, the above-mentioned dead time determination method is realized.

[0018] An embodiment of the present invention further provides a computer-readable storage medium for solving the technical problem that a power device in a conventional charging station adopts a dead time of a certain length, resulting in a long charging time required to charge an electric vehicle, the computer-readable storage medium storing a computer program for executing the above-mentioned dead time determination method.

[0019] In an embodiment of the present invention, the output current of the charging drive circuit is collected, and then the load state of the charging drive circuit is determined based on the output current of the charging drive circuit; the output voltage of the charging drive circuit is collected, and then the dead time of the charging drive circuit is determined based on the output voltage and load state of the charging drive circuit, thereby obtaining the dead time of the charging drive circuit under different load states, ensuring sufficient soft switching, and allowing the charging device to output a stable voltage or current.

[0020] In order to more clearly describe the embodiments of the present invention or the technical solutions in the prior art, the following will briefly describe the drawings used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without making inventive efforts. [Brief explanation of the drawings]

[0021] [Figure 1] 1 is a schematic diagram of a charging driving circuit provided by an embodiment of the present invention; [Figure 2] 1 is a schematic diagram of a MOS driver circuit provided by an embodiment of the present invention; [Figure 3] 1 is a flowchart of a dead time determination method provided by an embodiment of the present invention; [Figure 4] 1 is a flowchart illustrating a specific implementation of the dead time determination method provided by an embodiment of the present invention; [Figure 5] 1 is a schematic diagram of a computer device provided by an embodiment of the present invention;

[0022] Explanation of symbols 10, power supply module; 20, voltage acquisition module; 30, current collection module; 40, transistor drive circuit; 50, transistor switch circuit; 60, micro control unit; 70, computer equipment; 701, memory; 702, processor. DETAILED DESCRIPTION OF THE INVENTION

[0023] In order to make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be described in more detail below with reference to the drawings, wherein the exemplary embodiments of the present invention and the description thereof are for interpreting the present invention but are not intended to limit the present invention.

[0024] An embodiment of the present invention provides a charging driving circuit. FIG. 1 is a schematic diagram of the charging driving circuit provided by the embodiment of the present invention. As shown in FIG. 1, the charging driving circuit includes a power supply module 10, a voltage collecting module 20, a current collecting module 30, a transistor driving circuit 40, a transistor switch circuit 50, and a microcontroller unit 60; Here, the power supply module 10 is connected to a power supply device and is used to provide a power supply voltage; The transistor switch circuit 50 is connected to a load device and is used to supply power to the load device. The transistor driving circuit 40 is connected between the microcontroller unit 60 and the transistor switch circuit 50, and is used to drive the transistor switch circuit to turn on and off. The voltage collecting module 20 is connected to the output terminal of the transistor switch circuit 50 and is used to collect the output voltage of the transistor switch circuit 50; the current collecting module 30 is connected to the output terminal of the transistor switch circuit 50 and is used to collect the output current of the transistor switch circuit 50; The microcontrol unit 60 is connected to the voltage collection module 20 and the current collection module 30, respectively, and is used to generate a control signal for controlling the on / off of the transistor switch circuit 50 based on the output voltage and output current of the transistor switch circuit 50.

[0025] In specific implementation, the microcontroller unit 60 may include an acquisition unit, a determination unit, and a calculation unit, where the acquisition unit is used to acquire the output voltage and output current of the charging drive circuit, the determination unit is used to determine the load state of the charging drive circuit according to the output current, and the calculation unit is used to calculate the dead time of the charging drive circuit according to the output voltage and the load state.

[0026] The control signal output from the microcontroller unit 60 may be a square wave signal, which controls the on / off of the transistor switch circuit by outputting high and low levels. When the transistor switch circuit is turned on, it transfers energy to the voltage output terminal, and controls the on-time and on-speed of the transistor switch circuit to adjust the output voltage, thereby outputting a stable DC voltage.

[0027] In one embodiment, the transistors in the embodiments of the present invention are field effect transistors (MOS), since MOS has the advantage of being smaller and more energy-efficient.

[0028] In the charging driver circuit provided by the embodiment of the present invention, the microcontroller unit is implemented by a single-chip microcomputer. In one embodiment, the single-chip microcomputer can adopt a chip with model number TMS320F280049CPZS. The TMS320F280049 has a main frequency of 100MHz, is powerful, and has many on-chip analog peripherals.

[0029] In order to achieve compatibility between half-bridge circuits and full-bridge circuits, in one embodiment, in the charging driver circuit provided by the embodiment of the present invention, the transistor driver circuit is realized by a first driver chip and a second driver chip, and the first driver chip and the second driver chip are dual-channel isolated gate drivers with dual input interfaces for driving half-bridge circuits or full-bridge circuits. Figure 2 is a schematic diagram of the MOS driver circuit provided by the embodiment of the present invention, where U1 and U2 in Figure 2 are the first driver chip and the second driver chip, respectively. In this specification, the model numbers of the chips used for the first driver chip and the second driver chip are UCC21520.

[0030] The UCC21520 is an isolated dual-channel gate driver with a peak source current of 4 A and a peak sink current of 6 A. It supports high switching frequencies and has high insulation strength, and is used to drive metal-oxide-semiconductor field-effect transistors (MOSFETs) and insulated gate bipolar transistors (IGBTs). In this specification, the drive and control sections of the first and second driver chips are isolated from each other, and the two internal drive channels are also isolated from each other.

[0031] An embodiment of the present invention further provides a charging device including any of the above charging driving circuits.

[0032] It should be noted that the charging device provided by the embodiment of the present invention may be, but is not limited to, a charging device for an electric vehicle.

[0033] An embodiment of the present invention further provides a dead time determination method for determining the dead time of a charging drive circuit in real time, which can determine the dead time of the charging drive circuit, but is not limited to this.

[0034] FIG. 3 is a flowchart of a dead time determining method provided by an embodiment of the present invention. As shown in FIG. 3, the method includes the following steps:

[0035] S301, obtain the output current of the charging drive circuit;

[0036] S302, determining the load state of the charge driving circuit based on the output current of the charge driving circuit;

[0037] S303, obtain the output voltage of the charging drive circuit;

[0038] S304, determining the dead time of the charge drive circuit based on the output voltage and load state of the charge drive circuit;

[0039] In the embodiment of the present invention, the dead time is a protection period set to prevent the upper and lower transistors in a full-bridge circuit or a half-bridge circuit from being turned on simultaneously due to their switching speed. The output current of the charge drive circuit is the output current of the transistor switch circuit, and the output voltage of the charge drive circuit is the output voltage of the transistor switch circuit. Determining the load state of the charge drive circuit based on the output current of the charge drive circuit can be specifically achieved by determining the load state of the charge drive circuit as a loaded state if the output current of the charge drive circuit is greater than a first predetermined threshold, and determining the load state of the charge drive circuit as an idling state if the output current of the charge drive circuit is less than a second predetermined threshold. Here, the first predetermined threshold is greater than the second predetermined threshold; for example, the first predetermined threshold is in the range of 0.15 to 0.3 A, and the second predetermined threshold is in the range of 0.05 to 0.1 A.

[0040] In an embodiment of the present invention, the loaded state includes an idling state or a loaded state.

[0041] In the embodiments of the present invention, the idle state refers to a state in which the charging drive circuit is connected to a load device but is not charging, and the load-on state refers to a state in which the charging drive circuit is connected to a load device and is charging.

[0042] In one embodiment, a dead time determination method provided by an embodiment of the present invention can determine the dead time y1 during which the charging drive circuit is in an idle state by first calculating a first product of a proportionality coefficient k and an input voltage x, and then calculating the sum of the first product and a bias constant b as the dead time y1 during which the charging drive circuit is in an idle state. In one embodiment, the dead time y1 during which the charging drive circuit is in an idle state is calculated using equation (1).

[0043]

number

[0044] where y1 represents the dead time when the charging drive circuit is in an idle state, k represents a proportionality coefficient in time units, x represents the input voltage, and b represents a bias constant.

[0045] Furthermore, the dead time determining method provided by the embodiment of the present invention can determine the dead time y when the charge drive circuit is in a load-on state by the steps of: calculating a second product of the ratio of the system clock frequency f to the operating frequency Fsw and a first coefficient; calculating a difference between the dead time y1 when the charge drive circuit is in an idling state and the second product; and calculating the product of the difference and the second coefficient as the dead time y when the charge drive circuit is in a load-on state. In one embodiment, the dead time when the charge drive circuit is in a load-on state is calculated by equation (2), where the first coefficient is equal to 0.3 and the second coefficient is equal to 10.

[0046]

number

[0047] Here, y represents the dead time when the charge drive circuit is in a load state, f represents the system clock frequency and has a value range of 0 to 16 KHz, and Fsw represents the operating frequency and has a value range of 50 to 60 Hz.

[0048] FIG. 4 is a flowchart showing a specific implementation of the dead time determining method provided by an embodiment of the present invention. As shown in FIG. 4, S401, in which a microcontroller unit outputs a square wave signal to drive a transistor switch circuit; S402: collecting an output voltage of the transistor switch circuit by a voltage collecting module; S403: collecting the output current of the transistor switch circuit by a current collecting module, and judging whether the charging drive circuit is in an idle state according to the collected output current; if the charging drive circuit is not in an idle state, execute S404; if the charging drive circuit is in an idle state, execute S405; S404: calculating a dead time during which the charge drive circuit is in a load-applied state; S405: calculating a dead time during which the charging drive circuit is in an idling state; S406 adjusts the dead time, and S407, controlling the transistor switch circuit to output a stable voltage and current.

[0049] When the charge drive circuit is in an idle state, the dead time varies depending on the input voltage. The input voltage can range from 30 to 400 V. To operate the charge drive circuit in the soft switching region depending on the input voltage, the system operating frequency range is first adjusted and determined. For example, when the idle operating frequency range is 165 K, the dead time range is 1900 ns to 400 ns. The dead time when the charge drive circuit is in an idle state can be calculated using the above formula (1). When the charge drive circuit is in a load-applied state, the dead time when the charge drive circuit is in a load-applied state can be calculated using the above formula (2) based on the dead time y1 when the charge drive circuit is in an idle state, the operating frequency Fsw (a PID (Proportion Integration Differentiation) adjustment method can be used to adjust the operating frequency based on the output voltage value), and the system clock frequency f. The transistor switch circuit can then be controlled to output a stable voltage and current based on the dead time when the charge drive circuit is in a load-applied state.

[0050] It should be noted that, according to different output voltages and output currents, the system operating frequency band of the charging driver circuit in the embodiment of the present invention may be 90K~165K, and the dead time range may be 400ns~900ns.

[0051] In order to improve the overall system operation, increase efficiency, and meet customer needs, in one embodiment, the dead time determination method provided by the embodiment of the present invention can further switch between an idle state and a load state.

[0052] For example, when the charging drive circuit operates in an idling state, if the output current of the transistor switch circuit becomes larger than a first predetermined threshold (e.g., 0.2 A), the charging drive circuit switches from the idling state to a load-on state, and when the output current of the transistor switch circuit becomes smaller than a second predetermined threshold (e.g., 0.1 A), the charging drive circuit switches from the load-on state to the idling state.

[0053] Furthermore, the load device in the embodiments of the present invention is a high-power load device. When the load device is an electric vehicle, the charging drive circuit provided by the embodiments of the present invention can be installed in a charging station. By installing the charging drive circuit provided by the embodiments of the present invention in an electric vehicle charging station, the goal of fast and stable charging of the electric vehicle can be achieved. The charging drive circuit provided by the embodiments of the present invention has a simple design, easy component replacement, and strong market competitiveness. The method for determining the dead time of the charging drive circuit provided by the embodiments of the present invention is practical and simple.

[0054] An embodiment of the present invention further provides a computer device to solve the technical problem that the power devices in conventional charging stations adopt a fixed dead time, resulting in a long charging time for charging electric vehicles. FIG. 5 is a schematic diagram of the computer device provided by the embodiment of the present invention. As shown in FIG. 5, the computer device 70 includes a memory 701, a processor 702, and a computer program stored in the memory 701 and operable by the processor 702. When the processor 702 executes the computer program, the above-mentioned dead time determination method is realized.

[0055] An embodiment of the present invention further provides a computer-readable storage medium for solving the technical problem that a power device in a conventional charging station adopts a dead time of a certain length, resulting in a long charging time required to charge an electric vehicle, the computer-readable storage medium storing a computer program for executing the above-mentioned dead time determination method.

[0056] As described above, the charging drive circuit, charging device, dead time determination method, computer equipment, and computer-readable storage medium provided by embodiments of the present invention use a voltage collection module to collect the output voltage of the transistor drive circuit and a current collection module to collect the output current of the transistor drive circuit, thereby facilitating the microcontroller to generate a control signal for controlling the on / off of the transistor switch circuit based on the output voltage and output current of the transistor switch circuit, so that the transistor switch circuit outputs a stable voltage to supply power to the load device.The charging drive circuit and its dead time determination method provided by embodiments of the present invention can make the charging device output a stable voltage or current to the load device.

[0057] Those skilled in the art should understand that embodiments of the present invention may be provided as a method, a system, or a computer program product. Therefore, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. The present invention may also take the form of a computer program product embodied in one or more computer-usable storage media (including, but not limited to, magnetic disk memory, CD-ROM, optical memory, etc.) containing computer-usable program code.

[0058] The present invention has been described with reference to flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and combinations of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate an apparatus for implementing the functions specified in one or more flows in the flowcharts and / or one or more blocks in the block diagrams, such that the instructions, executed by a processor of the computer or other programmable data processing device, generate an apparatus.

[0059] These computer program instructions may be stored in a computer-readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, thereby producing an article of manufacture including an instruction apparatus that implements the functions specified in one or more flows of the flowcharts and / or one or more blocks of the block diagrams, with the instructions stored in the computer-readable memory.

[0060] These computer program instructions can be loaded into a computer or other programmable data processing device, whereby the computer or other programmable device generates a computer-implemented process by executing a series of operational steps, whereby the instructions executed by the computer or other programmable device provide steps for implementing the functions specified in one or more flows of the flowcharts and / or one or more blocks of the block diagrams.

[0061] The specific embodiments described above have further explained the objectives, technical solutions and beneficial effects of the present invention, but it should be understood that the above are only specific embodiments of the present invention and are not intended to limit the scope of the present invention. Any amendments, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should all be included within the scope of the present invention.

Claims

1. 1. A dead time determination method for determining a dead time of a charge drive circuit in real time, comprising: Obtaining an output current of a charge drive circuit; determining a load state of the charge drive circuit based on an output current of the charge drive circuit; acquiring an output voltage of the charge drive circuit; determining a dead time of the charge drive circuit based on an output voltage of the charge drive circuit and the load state; Determining a load state of the charge drive circuit based on an output current of the charge drive circuit determining a load state of the charge drive circuit as a loaded state when the output current of the charge drive circuit is greater than a first predetermined threshold; and determining a load state of the charging drive circuit as an idling state if the output current of the charging drive circuit is less than a second predetermined threshold. A dead time determination method.

2. The load state is an idling state or a loaded state.

2. The method for determining a dead time according to claim 1.

3. The dead time y during which the charging drive circuit is in an idling state １ To determine First, calculate the product of the proportionality coefficient k and the input voltage x; Next, the sum of the product and the bias constant b is calculated as the dead time y during which the charging drive circuit is in an idling state. １ and calculating the amount as follows:

3. The method for determining a dead time according to claim 2.

4. Determining the dead time y during which the charge drive circuit is in a load state comprises: calculating a product of a ratio of a system clock frequency f to an operating frequency and a first coefficient; The dead time y during which the charging drive circuit is in an idling state １ calculating a difference between the product and and calculating the product of the difference and a second coefficient as the dead time y during which the charge drive circuit is in a load-applied state.

4. The method for determining a dead time according to claim 3.

5. The first predetermined threshold is greater than the second predetermined threshold.

2. The method for determining a dead time according to claim 1.

6. A charging driving circuit including a power supply module, a voltage collecting module, a current collecting module, a transistor driving circuit, a transistor switch circuit, and a microcontrol unit, the power supply module is adapted to be connected to a power supply device to provide a power supply voltage; the transistor switch circuit is connected to a load device and is used to supply power to the load device; the transistor drive circuit is connected between the microcontroller unit and the transistor switch circuit, and is used to drive the transistor switch circuit to turn on and off; the voltage collection module is connected to the output terminal of the transistor switch circuit and is used to collect the output voltage of the transistor switch circuit; the current collecting module is connected to the output terminal of the transistor switch circuit and is used to collect the output current of the transistor switch circuit; the microcontrol unit is connected to the voltage collection module and the current collection module, respectively, and is configured to determine a dead time of the charge drive circuit based on an output voltage of the transistor switch circuit and a load state of the charge drive circuit, and to generate a control signal for controlling the on / off of the transistor switch circuit based on the dead time; the load state of the charge drive circuit is determined based on an output current of the charge drive circuit; If the output current of the charge drive circuit is greater than a first predetermined threshold, the load state of the charge drive circuit is determined to be a loaded state; If the output current of the charging drive circuit is less than a second predetermined threshold, the load state of the charging drive circuit is determined as an idling state. A charging drive circuit comprising:

7. The transistor driving circuit is realized by a first driving chip and a second driving chip, and the first driving chip and the second driving chip are dual-channel isolated gate drivers with dual input interfaces for driving a half-bridge circuit or a full-bridge circuit.

7. The charging drive circuit according to claim 6.

8. The model number of the chip used for the first driver chip and the second driver chip is UCC21520.

8. The charging drive circuit according to claim 7.

9. The micro control unit an acquisition unit for acquiring the output voltage and output current of the charging drive circuit; a determining unit for determining a load state of the charging drive circuit based on the output current; a calculation unit for calculating a dead time of the charging drive circuit based on the output voltage and the load state.

7. The charging drive circuit according to claim 6.

10. A charging device comprising the charging drive circuit according to any one of claims 6 to 9.

11. A computer device including a memory, a processor, and a computer program stored in the memory and operable by the processor, When the processor executes the computer program, the dead time determining method according to any one of claims 1 to 5 is realized.

1. A computer device characterized by:

12. A computer program for executing the dead time determination method according to any one of claims 1 to 5 is stored. A computer-readable storage medium comprising:

Images