Electronic load control method, system, storage medium and electronic load

Abstract

The present invention discloses an electronic load control method, system, storage medium, and electronic load. The method first pre-conducts the MOSFET using a maximum preset on-voltage, thereby significantly shortening the MOSFET's response time. Simultaneously, after the maximum preset on-voltage is applied, the MOSFET is stopped from being applied for a second pre-conducting duration, ensuring that the MOSFET's current starts from zero. Ultimately, when the preset base voltage is applied, the slope of the MOSFET's rising current remains consistent with expectations. The electronic load control method of the present invention utilizes the concept of pre-conducting, not only directly and effectively shortening the MOSFET's response time but also ensuring that the output current's rising slope remains unchanged, sufficient to meet market demand and suitable for industrial promotion.

Description

Technical Field

[0001] The present invention relates to the field of electronic loads, and in particular to an electronic load control method, system, storage medium and electronic load. Background Art

[0002] In electronic loads, constant current mode is one of the most important functions. In this mode, the response speed of the start-up, the current rating, and the current accuracy are all important indicators of the electronic load. An electronic load is a device that uses the linear region of MOSFET as a variable resistor to consume electrical energy. When the gate-source voltage VGS of MOSFET is constant in the constant current region (amplification state), the current I D Does not change with drain-source voltage V DS The output current of the MOS tube can be kept constant by changing V GS The value of can be used to change the magnitude of the constant current in the output circuit. During normal use of an electronic load, a conduction control voltage is output to the MOSFET. After a certain response time, the MOSFET outputs current and enters the linear amplification region, starting operation. The time from the start of outputting the conduction control voltage to the appearance of the output current is defined as the response time. However, when using the aforementioned control method, the response time can take hundreds of microseconds or even milliseconds, which to some extent affects the efficient control of the electronic load. Therefore, how to effectively reduce the response time has become a pressing issue. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides an electronic load control method that can solve the problem of excessively long response time of current electronic loads.

[0004] The present invention also provides a system, a storage medium and an electronic load.

[0005] According to the electronic load control method of the first aspect of the present invention, the electronic load includes a plurality of MOSFETs, and the electronic load control method includes:

[0006] Outputting a maximum preset on-state voltage to the MOSFET, the output duration being a first pre-on-state duration;

[0007] Stop outputting voltage to the MOSFET, where the stopping duration is a second pre-conduction duration; the second pre-conduction duration is obtained according to the time required for the load controller of the electronic load to switch the output voltage;

[0008] Outputting a preset basic voltage to the MOSFET until the MOSFET outputs an output current corresponding to the preset basic voltage;

[0009] The first pre-conduction time is obtained by the following steps:

[0010] Outputting the maximum preset on-state voltage to the MOSFET and obtaining a current waveform of an output current of the MOSFET;

[0011] determining a current output starting point in the current waveform;

[0012] The first pre-on time is determined according to a time period from a corresponding moment when the maximum preset on-state voltage starts to be output to a corresponding moment when the current output starting point appears.

[0013] The electronic load control method according to the embodiment of the present invention has at least the following beneficial effects:

[0014] The electronic load control method of an embodiment of the present invention first pre-conducts the MOSFET using a maximum preset on-voltage, thereby significantly shortening the MOSFET's response time. Furthermore, after the maximum preset on-voltage is applied, the MOSFET is stopped for a second pre-conducting duration, ensuring that the MOSFET current starts from zero. Ultimately, when the preset base voltage is applied, the slope of the MOSFET's rising current remains consistent with expectations. The electronic load control method of an embodiment of the present invention utilizes the concept of pre-conducting, not only directly and effectively shortening the MOSFET's response time but also ensuring a constant rising slope of the output current, sufficient to meet market demand and suitable for industrial promotion.

[0015] According to some embodiments of the present invention, determining the first pre-on time according to a time duration from a corresponding moment when the maximum preset on-state voltage starts to be output to a corresponding moment when the current output starting point appears includes:

[0016] Determine the time from the corresponding moment when the maximum preset conduction voltage starts to be output to the corresponding moment when the current output starting point appears as the maximum pre-conduction time;

[0017] The first pre-conduction time is obtained according to the maximum pre-conduction time and the anti-peak preset time threshold.

[0018] According to some embodiments of the present invention, the first pre-conduction time is obtained by the following formula:

[0019] t1=t1max-N;

[0020] Where t1 is the first pre-conduction time, t1max is the maximum pre-conduction time, and N is the anti-spike preset time threshold.

[0021] According to some embodiments of the present invention, the anti-spike preset time threshold is 2 DA control cycles of the load controller.

[0022] According to some embodiments of the present invention, the second pre-on time is 2 DA control cycles of the load controller.

[0023] According to some embodiments of the present invention, the electronic load includes a plurality of constant current closed-loop control circuits, and the plurality of constant current closed-loop control circuits are arranged in a one-to-one correspondence with the plurality of MOSFETs. Each of the constant current closed-loop control circuits has a turn-on voltage input terminal, a feedback output terminal, and a current sampling terminal. The current sampling terminal is used to collect the output current of the corresponding MOSFET, the turn-on voltage input terminal is used to receive the maximum preset turn-on voltage and the preset basic voltage, the feedback output terminal is connected to the gate of the corresponding MOSFET, and the constant current closed-loop control circuit is used to adjust the output state of the feedback output terminal according to the voltage input by the turn-on voltage input terminal and the current collected by the current sampling terminal.

[0024] According to some embodiments of the present invention, the constant current closed-loop control circuit includes:

[0025] a sampling resistor, one end of which is connected to the source of the MOSFET and the other end of which is connected to the ground;

[0026] a differential amplifier, wherein the positive input terminal is connected to one end of the sampling resistor, and the negative input terminal is connected to the other end of the sampling resistor;

[0027] an error amplifier, wherein the positive input terminal is used to receive the maximum preset conduction voltage and the preset base voltage, the negative input terminal is connected to the output terminal of the differential amplifier, and the output terminal is connected to the gate of the MOSFET; the drain of the MOSFET is used to connect to the operating voltage;

[0028] a first voltage-dividing resistor, one end of which is connected to the drain of the MOSFET, and the other end of which is connected to the gate of the MOSFET;

[0029] A second voltage-dividing resistor has one end connected to the gate of the MOSFET and the other end connected to the ground.

[0030] According to an electronic load control system of an embodiment of a second aspect of the present invention, the electronic load includes a plurality of MOSFETs, and the electronic load control system includes:

[0031] A pre-on voltage output unit, configured to output a maximum preset on voltage to the MOSFET, the output duration being a first pre-on duration;

[0032] a suspending unit, configured to stop outputting voltage to the MOSFET, wherein the suspending duration is a second pre-conduction duration; the second pre-conduction duration is obtained based on the time required for the load controller of the electronic load to switch the output voltage;

[0033] a basic voltage output unit, configured to output a preset basic voltage to the MOSFET until the MOSFET outputs an output current corresponding to the preset basic voltage;

[0034] The first pre-conduction time is obtained by the following steps:

[0035] Outputting the maximum preset on-state voltage to the MOSFET and obtaining a current waveform of an output current of the MOSFET;

[0036] determining a current output starting point in the current waveform;

[0037] The first pre-on time is determined according to a time period from a corresponding moment when the maximum preset on-state voltage starts to be output to a corresponding moment when the current output starting point appears.

[0038] The analog-to-digital conversion system according to the embodiment of the present invention has at least the following beneficial effects:

[0039] The electronic load control system of an embodiment of the present invention first pre-conducts the MOSFET using a maximum preset on-voltage, thereby significantly shortening the MOSFET's response time. Furthermore, after the maximum preset on-voltage is applied, the second pre-conducting duration is stopped, ensuring that the MOSFET current starts from zero. Ultimately, when the preset base voltage is applied, the slope of the MOSFET's rising current remains consistent with expectations. By utilizing the pre-conducting principle, the electronic load control system of an embodiment of the present invention not only directly and effectively shortens the MOSFET's response time, but also ensures a constant rising slope of the output current, sufficient to meet market demand and suitable for industrial promotion.

[0040] According to an embodiment of the third aspect of the present invention, an electronic load includes a plurality of MOSFETs and a load controller, wherein the plurality of MOSFETs are all controlled by the load controller, and the load controller is used to execute the electronic load control method as described above.

[0041] Since the electronic load adopts all the technical solutions of the electronic load control method of the above embodiment, it at least has all the beneficial effects brought by the technical solutions of the above embodiment.

[0042] A computer-readable storage medium according to a fourth embodiment of the present invention stores computer-executable instructions for executing the electronic load control system method described in the first embodiment. Because the computer-readable storage medium incorporates all of the technical solutions of the electronic load control system method described in the aforementioned embodiment, it at least has all of the beneficial effects provided by the technical solutions of the aforementioned embodiment.

[0043] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0045] Figure 1 is a characteristic curve diagram of a MOSFET according to an embodiment of the present invention;

[0046] Figure 2 is a system schematic diagram of an electronic load according to an embodiment of the present invention;

[0047] Figure 3 is a characteristic curve diagram of controlling the operation of a MOSFET with a preset base voltage according to an embodiment of the present invention;

[0048] Figure 4 is a characteristic curve diagram of controlling MOSFET operation using an electronic load control method according to an embodiment of the present invention;

[0049] Figure 5 It is a characteristic curve diagram of the first pre-conduction time setting process length when controlling MOSFET operation;

[0050] Figure 6 1 is a characteristic curve diagram of controlling the operation of a MOSFET at a maximum preset on-voltage according to an embodiment of the present invention;

[0051] Figure 7 1 is a schematic diagram of a constant current closed-loop control circuit according to an embodiment of the present invention;

[0052] Figure 8 is a flow chart of an electronic load control method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0053] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0054] In the description of the present invention, if there is a description of first, second, etc., it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0055] In the description of the present invention, it should be understood that descriptions involving orientation, such as the orientation or positional relationship indicated by up, down, etc., are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0056] In the description of the present invention, it should be noted that, unless otherwise clearly defined, terms such as setting, installing, and connecting should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0057] The technical solutions of the present invention will be described clearly and completely below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of the present invention, not all embodiments.

[0058] In order to better describe the electronic load control method of the embodiment of the present invention, a brief introduction to the electronic load is given here. Figure 2 As shown, the electronic load includes multiple MOSFETs, which are connected in parallel through the source and drain. The gate of each MOSFET is used to access the conduction control voltage (for example, a preset basic voltage Vref, a maximum preset conduction voltage Vmax). Under the control of the conduction control voltage, the current rises at a current slope corresponding to the conduction control voltage (for example, Figure 1 As shown, V GS The larger the current, the faster it rises to the linear operating area) and the corresponding response time (such as Figure 3As shown, there will be a response time before the current is generated, and before the maximum preset on-state voltage Vmax is exceeded, the larger the conduction control voltage, the shorter the response time) enters the linear working area, and the current in the constant current zone of the linear working area corresponding to different conduction control voltages is different, and the current slope rise rate is also different. Each MOSFET has a maximum preset on-state voltage Vmax, that is, when the conduction control voltage is greater than or equal to the maximum preset on-state voltage Vmax, the current slope rise rate of the MOSFET will not accelerate, but will remain at a constant speed. When the conduction control voltage is less than the maximum preset on-state voltage Vmax, the current slope rise rate will show a trend of faster. Under the traditional control method, if you want the MOSFET to enter the preset current value, the conduction control voltage corresponding to the preset current value will be used to constantly control the MOSFET to work, and finally the MOSFET will reach the preset current value. The response time in this process is relatively long.

[0059] Based on the above electronic load, various embodiments of the electronic load control method according to the present invention are proposed. The embodiments of the present invention are further described below with reference to the accompanying drawings.

[0060] like Figure 8 As shown, an embodiment of the present invention provides an electronic load control method, which includes but is limited to the following steps:

[0061] Outputting a maximum preset on-state voltage Vmax to the MOSFET, the output duration being the first pre-on-state duration t1;

[0062] Stop outputting voltage to the MOSFET, and the stopping time is the second pre-conduction time t2; the second pre-conduction time t2 is obtained according to the time required for the load controller of the electronic load to switch the output voltage;

[0063] Outputting a preset basic voltage Vref to the MOSFET until the MOSFET outputs an output current corresponding to the preset basic voltage Vref;

[0064] The first pre-conduction time t1 is obtained by the following steps:

[0065] Outputting a maximum preset on-state voltage Vmax to the MOSFET and obtaining a current waveform of an output current of the MOSFET;

[0066] Determine the current output starting point in the current waveform;

[0067] The first pre-on time t1 is determined according to a time duration from a corresponding moment when the maximum preset on-state voltage Vmax starts to be output to a corresponding moment when the current output starting point appears.

[0068] refer to Figure 4, firstly, the maximum preset on-state voltage Vmax is output to the gate of the MOSFET for the first pre-on time t1, so that the MOSFET can greatly shorten the response time under the control of the maximum preset on-state voltage Vmax; it should be noted that the time for controlling with the maximum preset on-state voltage Vmax needs to be strictly controlled. If the pressure is applied with the maximum preset on-state voltage Vmax for too long, it will cause a small spike in the current waveform (such as Figure 5 As shown), if the pressurization time continues to increase, it will cause current overshoot, and the instantaneous current will be greater than the preset current value. If the pressurization time continues to increase, the current is completely controlled by the maximum preset on-state voltage Vmax, and the maximum current of the output current loop (as shown) Figure 6 If the maximum preset on-state voltage (Vmax) is too short, the pre-turn-on function will be completely defeated. Instead, the added pre-turn-on step will waste time.

[0069] Continue to refer Figure 4 After the maximum preset on-state voltage Vmax is applied, a second pre-on duration t2 of waiting time is required. During this time period, the voltage output to the MOSFET is stopped, ensuring that the output current of the MOSFET can be output from 0 when the preset base voltage Vref is subsequently used. This ensures that the rate of increase of the current slope does not change due to the increase in the maximum preset on-state voltage Vmax control process, making the entire MOSFET turn-on process within a fully controllable range. It is understandable that any control may have errors. If there is no second pre-on duration t2 waiting, then after the maximum preset on-state voltage Vmax is applied for the first pre-on duration t1, it is likely that the MOSFET has already output current. At this time, although the output current is small, it is sufficient to affect the rate of increase of the current slope, thereby making the control of the MOSFET no longer precise. Furthermore, the second pre-conduction time t2 cannot be too long, as this will negate the effect of pre-conduction at the maximum preset conduction voltage Vmax, wasting time. Therefore, in this embodiment, the second pre-conduction time t2 is determined based on the time required for the load controller to switch the output voltage, that is, based on the time required for the load controller to switch from the maximum preset conduction voltage Vmax to the preset base voltage Vref. This ensures a certain waiting time while also ensuring that the preset base voltage Vref is output at the predetermined time after the switch is completed, as the switching instruction is executed. It should be noted that the first pre-conduction time t1 is typically several times the second pre-conduction time t2, or in other words, the duration of the load controller's DA control cycle needs to be significantly shorter than the first pre-conduction time t1.

[0070] Figure 4 As shown, after stopping the output of the second pre-conduction time t2, because the pre-conduction of the first pre-conduction time t1 and the current waiting for returning to zero and switching the output voltage control during the second pre-conduction time t2 have passed, the preset basic voltage Vref can be output to the MOSFET immediately. The MOSFET will rise to the linear working area at the current slope rising speed corresponding to the preset basic voltage Vref, that is, the output current of the MOSFET reaches the current preset value Iout and enters the working state.

[0071] The electronic load control method of an embodiment of the present invention first pre-conducts the MOSFET using a maximum preset on-voltage (Vmax), thereby significantly shortening the MOSFET's response time. Furthermore, after the maximum preset on-voltage (Vmax) is applied, the MOSFET is stopped for a second pre-conducting time (t2), ensuring that the MOSFET current starts from zero. Ultimately, when the preset base voltage (Vref) is applied, the slope of the MOSFET's rising current remains consistent with expectations. By utilizing the concept of pre-conducting, the electronic load control method of an embodiment of the present invention not only directly and effectively shortens the MOSFET's response time, but also ensures a constant rising slope of the output current, sufficient to meet market demand and suitable for industrial promotion.

[0072] In some embodiments, the first pre-on time t1 is determined according to the time from the corresponding moment when the maximum preset on-state voltage Vmax starts to be output to the corresponding moment when the current output starts, including:

[0073] The time duration from the corresponding moment when the maximum preset conduction voltage Vmax starts to be output to the corresponding moment when the current output starts is determined as the maximum pre-conduction time duration t1max;

[0074] The first pre-conduction time t1 is obtained according to the maximum pre-conduction time t1max and the anti-spike preset time threshold.

[0075] like Figure 5As shown, in order to avoid the first pre-conduction time t1 being too long or too short, it is necessary to select the most accurate time possible. In this embodiment, the conduction control voltage is directly applied to the MOSFET with the maximum preset conduction voltage Vmax, and then the waveform of the output current is captured by an oscilloscope, so that it can be determined how short a time the MOSFET can output current under the control of the maximum preset conduction voltage Vmax. The duration required for this process can be determined as the maximum pre-conduction time t1max. After determining the maximum pre-conduction time t1max, it is necessary to further consider the problem of errors in actual engineering, and it is necessary to reserve a time threshold for the anti-spike preset time threshold, that is, the maximum pre-conduction time t1max is appropriately shortened to obtain the first pre-conduction time t1.

[0076] In some embodiments, the first pre-on time t1 is obtained by the following formula:

[0077] t1=t1max-N;

[0078] Wherein, t1 is the first pre-conduction time length t1, t1max is the maximum pre-conduction time length t1max, and N is the anti-spike preset time threshold.

[0079] The first pre-conduction time t1 can be directly and effectively determined using the above formula.

[0080] In some embodiments, the anti-spike preset time threshold is 2 DA control cycles of the load controller. 2 DA control cycles is the time required for most load controllers to switch control signals and adjust. In actual operation, the number of control cycles can be appropriately extended, but it cannot be reduced. In actual engineering, it is recommended to use a minimum number of 2 cycles as the anti-spike preset time threshold to maintain the effect of the aforementioned pre-pass process as much as possible and avoid the effect of the pre-pass process disappearing due to the waiting time being too long. It should be noted that if there are still spikes after 2 DA control cycles, the number of DA control cycles can be appropriately extended. Specifically, taking the N69200 electronic load as an example, the length of its DA control cycle is 1 microsecond, so the anti-spike preset time threshold only requires 2 microseconds.

[0081] In some embodiments, the second pre-conduction time t2 is two DA control cycles of the load controller. Two DA control cycles are the time required for most controllers to switch control signals and adjust. In most cases, the second pre-conduction time t2 can be controlled to be two DA control cycles to meet the requirements. Specifically, still taking the N69200 electronic load as an example, the duration of its DA control cycle is 1 microsecond, the maximum pre-conduction time t1max is 12 microseconds, the first pre-conduction time t1 is controlled at 10 microseconds, and the second pre-conduction time t2 is 2 microseconds. It should be noted that the DA control cycle of the load controller in different electronic loads is different. The first pre-conduction time t1 can be determined according to the above steps, while the second pre-conduction time t2 and the anti-spike preset time threshold can be directly determined as two DA control cycles.

[0082] In some embodiments, the electronic load includes multiple constant current closed-loop control circuits, and the multiple constant current closed-loop control circuits are arranged in a one-to-one correspondence with multiple MOSFETs. Each constant current closed-loop control circuit has a conduction voltage input terminal, a feedback output terminal, and a current sampling terminal. The current sampling terminal is used to collect the output current of the corresponding MOSFET, the conduction voltage input terminal is used to receive the maximum preset conduction voltage Vmax and the preset basic voltage Vref, the feedback output terminal is connected to the gate of the corresponding MOSFET, and the constant current closed-loop control circuit is used to adjust the output state of the feedback output terminal according to the voltage input by the conduction voltage input terminal and the current collected by the current sampling terminal.

[0083] When controlling MOSFET, if the conduction value is directly used to control the voltage output, it is an open-loop control logic, which may cause large fluctuations in MOSFET due to current changes and other reasons. This embodiment proposes a constant current closed-loop control circuit, which can achieve closed-loop control of MOSFET and ensure stable control.

[0084] Specifically, the constant current closed-loop control circuit includes:

[0085] The sampling resistor Rs has one end connected to the source of the MOSFET and the other end connected to the ground;

[0086] A differential amplifier U1, whose positive input terminal is connected to one end of the sampling resistor Rs, and whose negative input terminal is connected to the other end of the sampling resistor Rs;

[0087] The error amplifier U2 has a positive input terminal for receiving a maximum preset on-state voltage Vmax and a preset base voltage Vref, a negative input terminal connected to the output terminal of the differential amplifier U1, and an output terminal connected to the gate of the MOSFET; the drain of the MOSFET is used to connect to the operating voltage VBUS;

[0088] a first voltage-dividing resistor R1, one end of which is connected to the drain of the MOSFET, and the other end of which is connected to the gate of the MOSFET;

[0089] The second voltage-dividing resistor R2 has one end connected to the gate of the MOSFET and the other end connected to the ground.

[0090] Figure 7 In the circuit, the sampling resistor Rs and the differential amplifier U1 form a comparison amplifier circuit. The current of the MOSFET output circuit is converted into a voltage by the sampling resistor Rs and then fed back to the negative input terminal of the error amplifier U2 to realize the V GS The MOSFET output current is adjusted accordingly. When a preset base voltage Vref is given, if the voltage on the sampling resistor Rs is less than the preset base voltage Vref, that is, the negative input terminal of the error amplifier U2 is less than the positive input terminal, the error amplifier U2 increases its output, deepens the conduction degree of the MOSFET, and increases the MOSFET output loop current. If the voltage on the sampling resistor Rs is greater than the preset base voltage Vref, that is, the negative input terminal of the error amplifier U2 is greater than the positive input terminal, the error amplifier U2 reduces its output, and the MOSFET output loop current decreases. In this way, the circuit ultimately maintains a constant given value, achieving constant current operation. When not working, the MOS tube operates in the cutoff region. According to the previous introduction, if you want to increase the current response speed during operation, you can only make the MOSFET enter the linear amplification region in a shorter time.

[0091] The embodiment of the present invention further provides an electronic load control system, which includes: a pre-conduction voltage output unit, a suspension unit, and a basic voltage output unit;

[0092] A pre-on voltage output unit is used to output a maximum preset on voltage Vmax to the MOSFET, and the output duration is the first pre-on duration t1;

[0093] A suspending unit is used to stop outputting voltage to the MOSFET, and the suspending duration is the second pre-conduction duration t2; the second pre-conduction duration t2 is obtained according to the time required for the load controller of the electronic load to switch the output voltage;

[0094] a basic voltage output unit, configured to output a preset basic voltage Vref to the MOSFET until the MOSFET outputs an output current corresponding to the preset basic voltage Vref;

[0095] The first pre-conduction time t1 is obtained by the following steps:

[0096] Outputting a maximum preset on-state voltage Vmax to the MOSFET and obtaining a current waveform of an output current of the MOSFET;

[0097] Determine the current output starting point in the current waveform;

[0098] The first pre-on time t1 is determined according to a time duration from a corresponding moment when the maximum preset on-state voltage Vmax starts to be output to a corresponding moment when the current output starting point appears.

[0099] refer to Figure 4 , firstly, the maximum preset on-state voltage Vmax is output to the gate of the MOSFET for the first pre-on time t1, so that the MOSFET can greatly shorten the response time under the control of the maximum preset on-state voltage Vmax; it should be noted that the time for controlling with the maximum preset on-state voltage Vmax needs to be strictly controlled. If the pressure is applied with the maximum preset on-state voltage Vmax for too long, it will cause a small spike in the current waveform (such as Figure 5 As shown), if the pressurization time continues to increase, it will cause current overshoot, and the instantaneous current will be greater than the preset current value. If the pressurization time continues to increase, the current is completely controlled by the maximum preset on-state voltage Vmax, and the maximum current of the output current loop (as shown) Figure 6 If the maximum preset on-state voltage (Vmax) is too short, the pre-turn-on function will be completely defeated. Instead, the added pre-turn-on step will waste time.

[0100] Continue to refer Figure 4After the maximum preset on-state voltage Vmax is applied, a second pre-on duration t2 of waiting time is required. During this time period, the voltage output to the MOSFET is stopped, ensuring that the output current of the MOSFET can be output from 0 when the preset base voltage Vref is subsequently used. This ensures that the rate of increase of the current slope does not change due to the increase in the maximum preset on-state voltage Vmax control process, making the entire MOSFET turn-on process within a fully controllable range. It is understandable that any control may have errors. If there is no second pre-on duration t2 waiting, then after the maximum preset on-state voltage Vmax is applied for the first pre-on duration t1, it is likely that the MOSFET has already output current. At this time, although the output current is small, it is sufficient to affect the rate of increase of the current slope, thereby making the control of the MOSFET no longer precise. Furthermore, the second pre-conduction time t2 cannot be too long, as this will negate the effect of pre-conduction at the maximum preset conduction voltage Vmax, wasting time. Therefore, in this embodiment, the second pre-conduction time t2 is determined based on the time required for the load controller to switch the output voltage, that is, based on the time required for the load controller to switch from the maximum preset conduction voltage Vmax to the preset base voltage Vref. This ensures a certain waiting time while also ensuring that the preset base voltage Vref is output at the predetermined time after the switch is completed, as the switching instruction is executed. It should be noted that the first pre-conduction time t1 is typically several times the second pre-conduction time t2, or in other words, the duration of the load controller's DA control cycle needs to be significantly shorter than the first pre-conduction time t1.

[0101] like Figure 4 As shown, after stopping the output of the second pre-conduction time t2, because the pre-conduction of the first pre-conduction time t1 and the current waiting for returning to zero and switching the output voltage control during the second pre-conduction time t2 have passed, the preset basic voltage Vref can be output to the MOSFET immediately. The MOSFET will rise to the linear working area at the current slope rising speed corresponding to the preset basic voltage Vref and enter the working state.

[0102] The electronic load control system of the present invention first pre-conducts the MOSFET using the maximum preset on-state voltage Vmax, thereby significantly shortening the MOSFET's response time. Furthermore, after the maximum preset on-state voltage Vmax is applied, the MOSFET is stopped for a second pre-conducting time duration t2, ensuring that the MOSFET current starts from zero. Ultimately, when the preset base voltage Vref is applied, the slope of the MOSFET's rising current remains consistent with the expected value. By utilizing the pre-conducting principle, the electronic load control system of the present invention not only directly and effectively shortens the MOSFET's response time, but also ensures a constant rising slope of the output current, sufficient to meet market demand and suitable for industrial promotion.

[0103] An embodiment of the present invention further provides an electronic load, which includes a plurality of MOSFETs and a load controller. The plurality of MOSFETs are all controlled by the load controller, and the load controller is used to execute the electronic load control method as described above.

[0104] Since the electronic load adopts all the technical solutions of the electronic load control method of the above embodiment, it has at least all the beneficial effects brought by the technical solutions of the above embodiment, which will not be described in detail here.

[0105] In addition, an embodiment of the present invention further provides a computer-readable storage medium storing computer-executable instructions. The computer-executable instructions are executed by a processor or a control unit, enabling the processor to execute the electronic load control method in the above embodiment.

[0106] It will be understood by those skilled in the art that all or some of the steps and systems in the methods disclosed above can be implemented as software, firmware, hardware, and appropriate combinations thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on computer-readable media, which can include computer storage media or non-transitory media and communication media or transient media. As is well known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information such as computer-readable instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVDs) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and can be accessed by a computer. Furthermore, as is well known to those skilled in the art, communication media typically embodies computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media.

[0107] The embodiments of the present invention are described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in the relevant technical field without departing from the scope of the present invention.

Claims

1. An electronic load control method, characterized in that: The electronic load includes a plurality of MOSFETs, and the electronic load control method includes: Outputting a maximum preset on-state voltage to the MOSFET, the output duration being a first pre-on-state duration; Stop outputting voltage to the MOSFET, where the stopping duration is a second pre-conduction duration; the second pre-conduction duration is obtained according to the time required for the load controller of the electronic load to switch the output voltage; Outputting a preset basic voltage to the MOSFET until the MOSFET outputs an output current corresponding to the preset basic voltage; The first pre-conduction time is obtained by the following steps: Outputting the maximum preset on-state voltage to the MOSFET and obtaining a current waveform of an output current of the MOSFET; determining a current output starting point in the current waveform; Determine the first pre-conduction time according to a time duration from a corresponding moment when the maximum preset conduction voltage starts to be output to a corresponding moment when the current output starting point appears; The determining the first pre-on time according to the time from the corresponding moment when the maximum preset on-state voltage starts to be output to the corresponding moment when the current output starting point appears includes: Determine the time from the corresponding moment when the maximum preset conduction voltage starts to be output to the corresponding moment when the current output starting point appears as the maximum pre-conduction time; Obtaining the first pre-conduction time according to the maximum pre-conduction time and the anti-peak preset time threshold; The first pre-conduction time is obtained by the following formula: t1 = t1max-N; Wherein, t1 is the first pre-conduction time, t1max is the maximum pre-conduction time, and N is the anti-spike preset time threshold.

2. The electronic load control method according to claim 1, wherein: The anti-peak preset time threshold is 2 DA control cycles of the load controller.

3. The electronic load control method according to any one of claims 1 to 2, characterized in that: The second pre-conduction time is two DA control cycles of the load controller.

4. The electronic load control method according to claim 1, wherein: The electronic load includes multiple constant current closed-loop control circuits, and the multiple constant current closed-loop control circuits are arranged in a one-to-one correspondence with the multiple MOSFETs. Each of the constant current closed-loop control circuits has a conduction voltage input terminal, a feedback output terminal, and a current sampling terminal. The current sampling terminal is used to collect the output current of the corresponding MOSFET, the conduction voltage input terminal is used to receive the maximum preset conduction voltage and the preset basic voltage, the feedback output terminal is connected to the gate of the corresponding MOSFET, and the constant current closed-loop control circuit is used to adjust the output state of the feedback output terminal according to the voltage input by the conduction voltage input terminal and the current collected by the current sampling terminal.

5. The electronic load control method according to claim 4, characterized in that: The constant current closed-loop control circuit comprises: a sampling resistor, one end of which is connected to the source of the MOSFET and the other end of which is connected to the ground; a differential amplifier, wherein the positive input terminal is connected to one end of the sampling resistor, and the negative input terminal is connected to the other end of the sampling resistor; an error amplifier, wherein the positive input terminal is used to receive the maximum preset conduction voltage and the preset base voltage, the negative input terminal is connected to the output terminal of the differential amplifier, and the output terminal is connected to the gate of the MOSFET; the drain of the MOSFET is used to connect to the operating voltage; a first voltage-dividing resistor, one end of which is connected to the drain of the MOSFET, and the other end of which is connected to the gate of the MOSFET; A second voltage-dividing resistor has one end connected to the gate of the MOSFET and the other end connected to the ground.

6. An electronic load control system, characterized in that: The electronic load includes a plurality of MOSFETs, and the electronic load control system includes: A pre-on voltage output unit, configured to output a maximum preset on voltage to the MOSFET, the output duration being a first pre-on duration; a suspending unit, configured to stop outputting voltage to the MOSFET, wherein the suspending duration is a second pre-conduction duration; the second pre-conduction duration is obtained based on the time required for the load controller of the electronic load to switch the output voltage; a basic voltage output unit, configured to output a preset basic voltage to the MOSFET until the MOSFET outputs an output current corresponding to the preset basic voltage; The first pre-conduction time is obtained by the following steps: Outputting the maximum preset on-state voltage to the MOSFET and obtaining a current waveform of an output current of the MOSFET; determining a current output starting point in the current waveform; Determine the first pre-conduction time according to a time duration from a corresponding moment when the maximum preset conduction voltage starts to be output to a corresponding moment when the current output starting point appears; The determining the first pre-on time according to the time from the corresponding moment when the maximum preset on-state voltage starts to be output to the corresponding moment when the current output starting point appears includes: Determine the time from the corresponding moment when the maximum preset conduction voltage starts to be output to the corresponding moment when the current output starting point appears as the maximum pre-conduction time; Obtaining the first pre-conduction time according to the maximum pre-conduction time and the anti-peak preset time threshold; The first pre-conduction time is obtained by the following formula: t1 = t1max-N; Wherein, t1 is the first pre-conduction time, t1max is the maximum pre-conduction time, and N is the anti-spike preset time threshold.

7. An electronic load, characterized in that: The electronic load control method comprises a plurality of MOSFETs and a load controller, wherein the plurality of MOSFETs are controlled by the load controller, and the load controller is used to execute the electronic load control method according to any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the electronic load control method according to any one of claims 1 to 5.

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