Method, device and terminal for controlling maximum output current slope

Abstract

The present invention discloses a method, device and terminal for controlling the maximum output current slope, belonging to the field of electrical system design. In the method for controlling the maximum output current slope, three expected currents are calculated to obtain the expected output current, and the expected current at the current moment is updated according to the expected output current at the previous moment and the expected current increase slope, so as to enable the DCDC to perform output control according to the preset expected current increase slope when the load current is suddenly turned on; in addition, the design method for fine-tuning the expected current in the current closed-loop control process is not limited to the DCDC device itself. Therefore, this method is simple and effective, has better application applicability and stronger expandability.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of electrical system design, and particularly to a method, device and terminal for controlling the maximum output current slope. Background Art

[0002] With the further tightening of fuel consumption regulations, more and more 48V mild hybrid technology solutions have been favored by global automotive suppliers. As an important link between the 48V electrical network and the 12V electrical network, the 48V DCDC focuses on powering vehicle electrical appliances and improving fuel economy. However, autonomous vehicles have higher robustness requirements for vehicle power supply stability and more limp-home mode requirements.

[0003] In the current 48V electrical network system, there is no suitable maximum output current slope control strategy. Under conditions such as vehicle load jumps, the robustness of the vehicle electrical network decreases, and some limp-home modes cannot be effectively realized. For example, when a 12V load is suddenly turned on or there is a disturbance in the 12V electrical network, a large current pulse will occur in the 48V electrical network. Since there are resistances inside the 48V motor, bus, etc., these current pulses will cause the 48V voltage to fluctuate, affecting the normal use of the 48V system. Another example is that in the vehicle limp-home condition (battery failure, the condition where only the motor and DCDC are working), since the motor has limited ability to stabilize the voltage on the 48V side, if a 12V load is turned on at this time, the voltage disturbance on the 48V side will become very large, even interfering with the realization of the limp-home condition. Another example is that since the DCDC output response speed is faster than that of the 12V battery, when the 12V load changes, the DCDC will give priority to output response. If the current sensor of the 12V battery cannot detect a large current for a long time, the SOC / SOH of the battery cannot be accurately calculated, which will have a greater impact on the accurate control of the vehicle's 12V electrical network.

[0004] Therefore, for the 48V electrical network and the 12V electrical network, there is no suitable maximum output current slope control strategy to ensure the power supply safety of each electrical network and improve the robustness of the vehicle system. Summary of the Invention

[0005] The embodiments of the present invention provide a method, device and terminal for controlling the maximum output current slope, which can solve the problem that the maximum output current slope control strategy in the related technology cannot ensure the power supply safety of the electrical network.

[0006] The technical solutions are as follows:

[0007] On the one hand, the embodiments of the present invention provide a method for controlling the maximum output current slope, the method comprising:

[0008] Calculate a first reference current i_ref_1, where the first reference current i_ref_1 is used to characterize an expected current increase slope;

[0009] Calculate a second reference current i_ref_2, where the second reference current i_ref_2 is used to characterize an expected current upper limit;

[0010] Calculate a third reference current i_ref_3, where the third reference current i_ref_3 is used to characterize the maximum current that the product is allowed to output;

[0011] Take the minimum value among the first reference current i_ref_1, the second reference current i_ref_2, and the third reference current i_ref_3 as the expected output current i_ref for current closed-loop control;

[0012] Update the previous moment's reference current i_ref_old according to the expected output current i_ref.

[0013] On the other hand, an embodiment of the present invention provides a maximum output current slope control device, and the device includes:

[0014] A first calculation module, configured to calculate a first reference current i_ref_1, where the first reference current i_ref_1 is used to characterize an expected current increase slope;

[0015] A second calculation module, configured to calculate a second reference current i_ref_2, where the second reference current i_ref_2 is used to characterize an expected current upper limit;

[0016] A third calculation module, configured to calculate a third reference current i_ref_3, where the third reference current i_ref_3 is used to characterize the maximum current that the product is allowed to output;

[0017] An expected output module, configured to take the minimum value among the first reference current i_ref_1, the second reference current i_ref_2, and the third reference current i_ref_3 as the expected output current i_ref for current closed-loop control;

[0018] A current update module, configured to update the previous moment's reference current i_ref_old according to the expected output current i_ref.

[0019] On the other hand, an embodiment of the present invention provides a terminal, and the terminal includes a processor and a memory; the memory stores at least one instruction, and the at least one instruction is used to be executed by the processor to implement the maximum output current slope control method as described in the above aspect.

[0020] On the other hand, a computer-readable storage medium is provided, and the storage medium stores at least one instruction, and the at least one instruction is used to be executed by a processor to implement the maximum output current slope control method in the above aspects.

[0021] By using the maximum output current slope control method provided in the embodiment of the present invention, three expected currents are calculated to obtain an expected output current, and the expected current at the current moment is updated according to the expected output current at the previous moment and the expected current increase slope, so that when the load current is suddenly turned on, the DCDC can perform output control according to the expected current increase slope set in advance; in addition, the design method for fine-tuning the expected current in the current closed-loop control process is not limited to the DCDC product itself. Therefore, this method is simple and effective, has better application applicability, and stronger expandability. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The flowchart of the maximum output current slope control method shown in an exemplary embodiment of the present invention is shown;

[0023] Figure 2 The flowchart of the maximum output current slope control method shown in another exemplary embodiment of the present invention is shown;

[0024] Figure 3 The schematic diagram of the maximum output current slope control effect is shown;

[0025] Figure 4 The structural block diagram of the maximum output current slope control device provided in the embodiment of the present invention is shown;

[0026] Figure 5 The schematic diagram of the terminal structure corresponding to the maximum output current slope control method provided in the embodiment of the present invention is shown. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] To make the objectives, technical solutions and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the drawings.

[0028] As used herein, "a plurality of" means two or more. "And / or" describes the association relationship of associated objects and indicates that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally represents an "or" relationship between the associated objects before and after.

[0029] First, explanations are made for the nouns involved.

[0030] DCDC (Direct Current): It refers to a device that converts a DC power supply of a certain voltage level into a DC power supply of other voltage levels. DCDC can be classified into two categories: boost power supply and buck power supply according to the voltage level conversion relationship, and isolated power supply and non-isolated power supply according to the input-output relationship. For example, the DCDC converter connected to the in-vehicle DC power supply converts high-voltage DC power into low-voltage DC power. For example, it converts a DC voltage (3.0V) into other DC voltages (1.5V or 5.0V). We call this converter a DC / DC converter, or a switching power supply or a switching regulator. Specifically, it means converting the input DC power into AC power through a self-excited oscillation circuit, then changing the voltage through a transformer and converting it back into DC power output, or converting AC power into high-voltage DC power output through a voltage multiplier rectifier circuit.

[0031] In various embodiments of the present application, a 12V power network is taken as an example for illustrative purposes.

[0032] Please refer to Figure 1 , which shows the flowchart of the maximum output current slope control method shown in the exemplary embodiments of the present invention. The method includes:

[0033] Step 101, calculate the first desired current i_ref_1.

[0034] Among them, the first desired current i_ref_1 is used to characterize the desired current increase slope, which will be activated when the load increases. When the load increases, let the DCDC output current according to the desired maximum current slope.

[0035] Step 102, calculate the second desired current i_ref_2.

[0036] Among them, the second desired current i_ref_2 is used to characterize the desired current upper limit, and this desired current is generally not activated during the current loop control process (such as the voltage loop).

[0037] Step 103, calculate the third desired current i_ref_3.

[0038] Among them, the third desired current i_ref_3 is used to characterize the maximum current that the product is allowed to output. The purpose of this current limit is to protect the product. After the maximum load current is greater than the product limit, let the product enter the output derating mode.

[0039] Step 104, take the minimum value among the first desired current i_ref_1, the second desired current i_ref_2, and the third desired current i_ref_3 as the desired output current i_ref of the current closed-loop control.

[0040] Further, after calculating the three expected currents, find the minimum value as the expected output current i_ref of the current closed-loop control.

[0041] Step 105, update the expected current i_ref_old at the previous moment according to the expected output current i_ref.

[0042] In a possible implementation manner, update the expected current i_ref_old at the previous moment according to the expected output current i_ref, such as updating the real-time current increase situation in the first expected current i_ref_1.

[0043] In the embodiment of the present application, a maximum output current slope control method is provided. By calculating three expected currents, the expected output current is obtained, and the expected current at the current moment is updated according to the expected output current and the expected current increase slope at the previous moment, so that when the load current is suddenly turned on, DCDC can perform output control according to the expected current increase slope set in advance; in addition, the design method for fine-tuning the expected current in the current closed-loop control process is not limited to the DCDC product itself. Therefore, this method is simple and effective, has better application applicability, and stronger expandability.

[0044] Please refer to Figure 2 , which shows the flowchart of the maximum output current slope control method shown in another exemplary embodiment of the present invention. The method includes:

[0045] Step 201, collect the DCDC expected output current situation, and the DCDC expected output current situation includes at least the expected current i_ref_old at the previous moment and the load current i_Act.

[0046] Step 202, calculate the first expected current i_ref_1.

[0047] In the embodiment of the present application, step 202 includes the following content one and two.

[0048] Content one: Obtain i_ref_old from the DCDC expected output current situation.

[0049] Content two: Calculate the first expected current i_ref_1 according to the predetermined slope parameter I_DES_GRAD and the expected current i_ref_old at the previous moment.

[0050] Among them, calculate the expected current increase slope, which will be activated when the load increases. According to the pre-calibrated slope parameter I_DES_GRAD, when the load increases, let DCDC output current according to the expected maximum current slope.

[0051] Step 203, calculate the second expected current i_ref_2.

[0052] In the embodiment of the present application, step 203 includes the following contents one and two.

[0053] Content one: Obtain the load current i_Act from the DCDC expected output current situation.

[0054] Content two: Calculate the second expected current i_ref_2 according to the calibrated current I_GAP and the load current i_Act.

[0055] Among them, calculate the upper limit of the expected current, which is generally not activated during the current loop control process (such as the voltage loop). The purpose of this signal is to update the expected current i_ref_old at the previous moment in real time.

[0056] Step 204: Calculate the third expected current i_ref_3.

[0057] In the embodiment of the present application, step 204 includes the following contents one and two.

[0058] Content one: Obtain the product current limit.

[0059] Content two: Calculate the third expected current i_ref_3 according to the product current limit.

[0060] Among them, calculate the maximum current that the product allows to output. The purpose of this current limit is to protect the product. After the maximum load current is greater than the product limit, the product is in the output derating mode.

[0061] Step 205: Take the minimum value among the first expected current i_ref_1, the second expected current i_ref_2, and the third expected current i_ref_3 as the expected output current i_ref of the current closed-loop control.

[0062] Step 206: Update the expected current i_ref_old at the previous moment according to the expected output current i_ref.

[0063] Step 207: In response to the load current i_Act being greater than the expected output current i_ref, perform output current closed-loop control according to the expected output current i_ref.

[0064] Step 208: In response to the load current i_Act not being greater than the expected output current i_ref, perform non-current closed-loop control.

[0065] In a possible implementation, when the 12V load current i_Act suddenly increases, the situation of i_Act > i_ref will occur. At this time, the current closed-loop will intervene in the control and control the magnitude of the DCDC current slope output according to the desired current. When the increase rate of the 12V load current i_Act is slow, then i_Act cannot be greater than the desired current i_ref because the update rate of i_ref according to the desired slope is faster. As a result, the maximum current slope does not need to intervene in the control, and this working condition does not need to intervene either.

[0066] Schematically, the control effect diagram of the maximum output current slope control scheme is as Figure 3 shown. It can be seen that when the current slope control is not activated, the desired current is always larger than the actual output current by a calibratable fixed value (I_GAP).

[0067] When the increase slope of the 12V real load is fast, at this time the desired current increases according to the fixed maximum current increase slope, so as to achieve the purpose of the DCDC output current.

[0068] When the load remains unchanged, changes slowly or the load decreases, the maximum output current slope control rate will not be in the activated state.

[0069] Please refer to Figure 4 , which shows the structural block diagram of the maximum output current slope control device provided by the embodiment of the present invention. This device can be implemented as all or part of the terminal through software, hardware or a combination of both. In the embodiment of the present invention, this device includes:

[0070] A first calculation module 401, configured to calculate a first desired current i_ref_1, where the first desired current i_ref_1 is used to characterize the desired current increase slope;

[0071] A second calculation module 402, configured to calculate a second desired current i_ref_2, where the second desired current i_ref_2 is used to characterize the desired current upper limit;

[0072] A third calculation module 403, configured to calculate a third desired current i_ref_3, where the third desired current i_ref_3 is used to characterize the maximum current that the product allows to output;

[0073] A desired output module 404, configured to use the minimum value among the first desired current i_ref_1, the second desired current i_ref_2, and the third desired current i_ref_3 as the desired output current i_ref for current closed-loop control;

[0074] A current update module 405, configured to update the previous moment's desired current i_ref_old according to the desired output current i_ref.

[0075] Optionally, the device further includes:

[0076] A situation acquisition module, configured to acquire the DCDC expected output current situation, where the DCDC expected output current situation at least includes the previous moment's expected current i_ref_old and the load current i_Act.

[0077] Optionally, the first calculation module 401 includes:

[0078] A first calculation unit, configured to obtain the i_ref_old from the DCDC expected output current situation;

[0079] A second calculation unit, configured to calculate the first expected current i_ref_1 according to a predetermined slope parameter I_DES_GRAD and the previous moment's expected current i_ref_old.

[0080] Optionally, the second calculation module 402 includes:

[0081] A third calculation unit, configured to obtain the load current i_Act from the DCDC expected output current situation;

[0082] A fourth calculation unit, configured to calculate the second expected current i_ref_2 according to a calibrated current I_GAP and the load current i_Act.

[0083] Optionally, the third calculation module 403 includes:

[0084] A fifth calculation unit, configured to obtain the product current limit;

[0085] A sixth calculation unit, configured to calculate the third expected current i_ref_3 according to the product current limit.

[0086] Optionally, the current update module 405 is further configured to:

[0087] Update the previous moment's expected current i_ref_old according to the expected output current i_ref.

[0088] Optionally, the device further includes:

[0089] A first control module, configured to, in response to the load current i_Act being greater than the expected output current i_ref, perform closed-loop control of the output current according to the expected output current i_ref;

[0090] A second control module, configured to, in response to the load current i_Act not being greater than the expected output current i_ref, perform non-current closed-loop control.

[0091] Please refer to Figure 5 , which shows a structural block diagram of a terminal 500 provided by an exemplary embodiment of the present invention. The terminal 500 may be an electronic device such as a smart phone, a tablet computer, an e-book, a portable personal computer, etc. that installs and runs application programs. The terminal 500 in the present invention may include one or more of the following components: a processor 510, a memory 520, and a screen 530.

[0092] The processor 510 may include one or more processing cores. The processor 510 uses various interfaces and lines to connect various parts within the entire terminal 500, and by running or executing instructions, programs, code sets, or instruction sets stored in the memory 520, and by calling data stored in the memory 520, it executes various functions of the terminal 500 and processes data. Optionally, the processor 510 may be implemented in at least one hardware form of digital signal processing (DSP), field-programmable gate array (FPGA), or programmable logic array (PLA). The processor 510 may integrate a combination of one or several of a central processing unit (CPU), a graphics processing unit (GPU), and a modem. Among them, the CPU mainly processes the operating system, user interface, application programs, etc.; the GPU is responsible for the rendering and drawing of the content required to be displayed on the screen 530; the modem is used to process wireless communication. It can be understood that the above modem may not be integrated into the processor 510 and may be implemented separately through a communication chip.

[0093] The memory 520 may include a Random Access Memory (RAM), or may also include a Read-Only Memory. Optionally, the memory 520 includes a non-transitory computer-readable storage medium. The memory 520 can be used to store instructions, programs, code, code sets, or instruction sets. The memory 520 may include a program storage area and a data storage area. Among them, the program storage area may store instructions for implementing an operating system, instructions for implementing at least one function (such as a touch function, a sound playback function, an image playback function, etc.), instructions for implementing the above various method embodiments, etc. The operating system may be an Android system (including a system developed based on the Android system with in-depth development), an IOS system developed by Apple Inc. (including a system developed based on the IOS system with in-depth development), or other systems. The data storage area may also store data created during the use of the terminal 500 (such as a phone book, audio and video data, chat record data, etc.).

[0094] The screen 530 may be a touch display screen, which is used to receive touch operations by a user using any suitable object such as a finger or a stylus on or near it, and to display the user interfaces of various application programs. The touch display screen is usually set on the front panel of the terminal 500. The touch display screen can be designed as a full-screen, a curved screen, or a special-shaped screen. The touch display screen can also be designed as a combination of a full-screen and a curved screen, or a combination of a special-shaped screen and a curved screen. The embodiments of the present invention do not limit this.

[0095] Embodiments of the present invention also provide a computer-readable medium, which stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement the maximum output current slope control method described in the above various embodiments.

[0096] Embodiments of the present invention also provide a computer program product, which stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement the maximum output current slope control method described in the above various embodiments.

[0097] Those skilled in the art should be able to realize that in one or more of the above examples, the functions described in the embodiments of the present invention can be implemented by hardware, software, firmware, or any combination thereof. When implemented using software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium. The computer-readable medium includes computer storage media and communication media, where the communication media includes any medium that facilitates the transmission of a computer program from one place to another. The storage media can be any available medium accessible by a general-purpose or special-purpose computer.

[0098] The above are only alternative embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A maximum output current slope control method, characterized in that, The method includes: Calculating a first reference current i_ref_1, where the first reference current i_ref_1 is used to represent a current value calculated according to a predetermined slope parameter I_DES_GRAD and the previous reference current i_ref_old; Calculating a second reference current i_ref_2, where the second reference current i_ref_2 is used to represent an upper limit of the desired current; Calculating a third reference current i_ref_3, where the third reference current i_ref_3 is used to represent the maximum current that the product is allowed to output; Taking the minimum value among the first reference current i_ref_1, the second reference current i_ref_2, and the third reference current i_ref_3 as the reference output current i_ref for current closed-loop control; Updating the previous reference current i_ref_old according to the reference output current i_ref; Among them, calculating the second reference current i_ref_2 includes: Collecting the DCDC desired output current situation, where the DCDC desired output current situation at least includes the previous reference output current i_ref_old and the load current i_Act; Obtaining the load current i_Act from the DCDC desired output current situation; Calculating the second reference current i_ref_2 according to the calibrated current I_GAP and the load current i_Act.

2. The maximum output current slope control method according to claim 1, characterized in that, The calculating the first reference current i_ref_1 includes: Obtaining the i_ref_old from the DCDC desired output current situation; Calculating the first reference current i_ref_1 according to the predetermined slope parameter I_DES_GRAD and the i_ref_old.

3. The maximum output current slope control method according to claim 1, characterized in that, The calculating the third reference current i_ref_3 includes: Obtaining the product current limit; Calculating the third reference current i_ref_3 according to the product current limit.

4. The maximum output current slope control method according to claim 1, characterized in that, The updating the previous reference current i_ref_old according to the reference output current i_ref includes: Updating the previous reference current i_ref_old according to the reference output current i_ref.

5. The maximum output current slope control method according to claim 1, characterized in that, The method further includes: In response to the load current i_Act being greater than the reference output current i_ref, performing output current closed-loop control according to the reference output current i_ref; In response to the load current i_Act not being greater than the reference output current i_ref, performing non-current closed-loop control.

6. A maximum output current slope control device, characterized in that, The device includes: A first calculation module for calculating a first reference current i_ref_1, where the first reference current i_ref_1 is a current value calculated according to a predetermined slope parameter I_DES_GRAD and the previous reference current i_ref_old; A second calculation module for calculating a second reference current i_ref_2, where the second reference current i_ref_2 is used to represent an upper limit of the desired current; A third calculation module for calculating a third reference current i_ref_3, where the third reference current i_ref_3 is used to represent the maximum current that the product is allowed to output; An expected output module for using the minimum value among the first expected current i_ref_1, the second expected current i_ref_2, and the third expected current i_ref_3 as the expected output current i_ref for current closed-loop control; A current update module for updating the previous moment's expected current i_ref_old according to the expected output current i_ref; A situation acquisition module for acquiring the DCDC expected output current situation, where the DCDC expected output current situation at least includes the previous moment's expected output current i_ref_old and the load current i_Act; Among them, the second calculation module includes: A third calculation unit for obtaining the load current i_Act from the DCDC expected output current situation; A fourth calculation unit for calculating the second expected current i_ref_2 according to the calibrated current I_GAP and the load current i_Act.

7. The maximum output current slope control device according to claim 6, wherein, The first calculation module includes: A first calculation unit for obtaining the i_ref_old from the DCDC expected output current situation; A second calculation unit for calculating the first expected current i_ref_1 according to the predetermined slope parameter I_DES_GRAD and the previous moment's expected output current i_ref_old.

8. The maximum output current slope control device according to claim 6, wherein, The third calculation module includes: A fifth calculation unit for obtaining the product current limit value; A sixth calculation unit for calculating the third expected current i_ref_3 according to the product current limit value.

9. The maximum output current slope control device according to claim 6, wherein, The current update module is further used for: Updating the i_ref_old according to the expected output current i_ref.

10. The maximum output current slope control device according to claim 6, wherein, The device further includes: A first control module for, in response to the load current i_Act being greater than the expected output current i_ref, performing output current closed-loop control according to the expected output current i_ref; A second control module for, in response to the load current i_Act not being greater than the expected output current i_ref, performing non-current closed-loop control.

11. A terminal, wherein, The terminal includes a processor and a memory; the memory stores at least one instruction, and the at least one instruction is used to be executed by the processor to implement the maximum output current slope control method according to any one of claims 1 to 5.

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