Power device switching speed control method, device and electric drive system

Abstract

The present disclosure relates to the field of electronic technology, and in particular to a method, device and electric drive system for controlling the switching speed of a power device. The method for controlling the switching speed of a power device comprises: determining a switching voltage stress threshold corresponding to the power device; detecting the switching voltage stress corresponding to the power device to obtain a switching voltage stress detection value; and adjusting the switching speed of the power device according to the switching voltage stress threshold and the switching voltage stress detection value. The present disclosure can reduce switching losses while ensuring the safety of the power device.

Description

Technical Field

[0001] The present disclosure relates to the field of electronic technology, and in particular to a method and device for controlling the switching speed of a power device and an electric drive system. Background Art

[0002] Power devices, also known as power electronic devices, refer to power semiconductor devices that are capable of handling high voltages and large currents. Power devices have two operating characteristics: on and off. As the switching speed of power devices increases, the switching loss of power devices will gradually decrease. However, the safety of power devices during the switching process will also decrease. Therefore, when controlling the switching speed of power devices, how to comprehensively consider the switching loss and safety of power devices so that the switching loss can be reduced while ensuring the safety of power devices has become a focus of attention. Summary of the invention

[0003] The present disclosure provides a method and device for controlling the switching speed of a power device and an electric drive system, the main purpose of which is to reduce switching losses while ensuring the safety of the power device.

[0004] According to one aspect of the present disclosure, a method for controlling a switching speed of a power device is provided, comprising:

[0005] Determine a switch voltage stress threshold corresponding to the power device;

[0006] Detecting the switch voltage stress corresponding to the power device to obtain a switch voltage stress detection value;

[0007] The switching speed of the power device is adjusted according to the switch voltage stress threshold and the switch voltage stress detection value.

[0008] Optionally, determining a switch voltage stress threshold corresponding to a power device includes:

[0009] Determine the bus voltage and withstand voltage corresponding to the power device;

[0010] The switch voltage stress threshold corresponding to the power device is determined according to the bus voltage and the withstand voltage.

[0011] Optionally, the power device is connected in series with the sampling inductor, and the switch voltage stress corresponding to the power device is detected to obtain a switch voltage stress detection value, including:

[0012] Detecting the inductor voltage of the sampling inductor to obtain an inductor voltage detection value;

[0013] Determine the loop inductance value corresponding to the power device;

[0014] The switch voltage stress detection value corresponding to the power device is determined according to the loop inductance value, the sampled inductance value corresponding to the sampled inductance, and the inductor voltage detection value.

[0015] Optionally, adjusting the switching speed of the power device according to the switch voltage stress threshold and the switch voltage stress detection value includes:

[0016] A control algorithm is used to determine a switch speed adjustment instruction according to a switch voltage stress threshold and a switch voltage stress detection value;

[0017] According to the switching speed adjustment instruction, the switching speed of the power device is adjusted.

[0018] Optionally, the switching speed of the power device is adjusted, including:

[0019] The driving current or the resistance value of the driving resistor corresponding to the power device is adjusted to adjust the switching speed of the power device, wherein the driving current refers to the current input to the control end of the power device, and the driving resistor refers to the resistor connected to the control end of the power device.

[0020] Optionally, adjusting the switching speed of the power device according to the switch voltage stress threshold and the switch voltage stress detection value includes:

[0021] Performing closed-loop control on the switch voltage stress according to the switch voltage stress threshold and the switch voltage stress detection value;

[0022] In the process of closed-loop control of the switch voltage stress, the switching speed of the power device is adjusted.

[0023] According to another aspect of the present disclosure, a power device switching speed control device is provided, the power device switching speed control device is connected to the power device, and the power device switching speed control device includes a control module, a sampling module and a driving resistance module; wherein,

[0024] The sampling module is connected in series with the power device, and the sampling output end of the sampling module is connected to the input end of the control module, the output end of the control module is connected to the first end of the driving resistance module, and the second end of the driving resistance module is connected to the control end of the power device;

[0025] The control module is used to determine the switch voltage stress threshold corresponding to the power device; the control sampling module detects the switch voltage stress corresponding to the power device to obtain the switch voltage stress detection value; and the switch speed of the power device is adjusted according to the switch voltage stress threshold and the switch voltage stress detection value.

[0026] Optionally, the sampling module includes a sampling inductor and an operational amplifier; wherein,

[0027] The sampling inductor is connected in series with the power device, the first input terminal of the operational amplifier is connected to the first terminal of the sampling inductor, the second input terminal of the operational amplifier is connected to the second terminal of the sampling inductor, and the output terminal of the operational amplifier is connected to the input terminal of the control module.

[0028] Optionally, the control module is also connected to the control end of the driving resistance module to adjust the resistance value corresponding to the driving resistance module.

[0029] According to another aspect of the present disclosure, an electric drive system is provided, comprising: at least one power device and at least one power device switching speed control device as described in any one of the above aspects; wherein,

[0030] The power device switching speed control device and the power device are connected in a one-to-one correspondence.

[0031] According to another aspect of the present disclosure, there is provided a power device switching speed control device, comprising:

[0032] at least one processor; and

[0033] a memory communicatively connected to the at least one processor; wherein,

[0034] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform any one of the methods described in the above aspect.

[0035] According to another aspect of the present disclosure, a non-transitory computer-readable storage medium storing computer instructions is provided, wherein the computer instructions are used to enable the computer to execute any one of the methods described in the above aspect.

[0036] According to another aspect of the present disclosure, a computer program product is provided, including a computer program, wherein when the computer program is executed by a processor, the computer program implements any one of the methods described in the aforementioned aspect.

[0037] In one or more embodiments of the present disclosure, by determining the switch voltage stress threshold corresponding to the power device; detecting the switch voltage stress corresponding to the power device to obtain the switch voltage stress detection value; adjusting the switch speed of the power device according to the switch voltage stress threshold and the switch voltage stress detection value. Therefore, since the safety of the power device is related to the switch voltage stress, the switch speed of the power device is adjusted according to the switch voltage stress corresponding to the power device, and the switch speed is maximized on the basis of ensuring the switch voltage stress, the switch loss of the power device at each switch can be minimized, and the switch loss can be reduced under the premise of ensuring the safety of the power device.

[0038] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings are used to better understand the present solution and do not constitute a limitation of the present disclosure.

[0040] Figure 1 A structural block diagram of an electric drive system provided by an embodiment of the present disclosure is shown;

[0041] Figure 2 A schematic diagram showing a process of calibrating the resistance value of a driving resistor provided by an embodiment of the present disclosure;

[0042] Figure 3 A schematic diagram showing a flow chart of a method for controlling a switching speed of a power device provided by an embodiment of the present disclosure;

[0043] Figure 4 A schematic flow chart showing another method for controlling the switching speed of a power device provided by an embodiment of the present disclosure is shown;

[0044] Figure 5 A closed-loop control block diagram of a power device switching speed provided by an embodiment of the present disclosure is shown;

[0045] Figure 6 A schematic structural diagram of a power device switching speed control device provided by an embodiment of the present disclosure is shown;

[0046] Figure 7 A schematic structural diagram of another power device switching speed control device provided by an embodiment of the present disclosure is shown;

[0047] Figure 8 The block diagram is a power device switching speed control apparatus for implementing the power device switching speed control method according to the embodiment of the present disclosure. DETAILED DESCRIPTION

[0048] The following is a description of exemplary embodiments of the present disclosure in conjunction with the accompanying drawings, including various details of the embodiments of the present disclosure to facilitate understanding, which should be considered as merely exemplary. Therefore, it should be recognized by those of ordinary skill in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. Similarly, for the sake of clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0049] Power devices are widely used in the field of electronic technology, including but not limited to electric drive systems in vehicles, motor controllers in the industrial field, photovoltaic inverters, wind power converters, and energy storage converters in the energy field.

[0050] In the electric drive system of an electric vehicle, the Micro Control Unit (MCU) sends a pulse width modulation (PWM) wave signal, which is converted into a gate-level signal that can drive the power device through an isolated drive. The gate-level signal is used to control the opening and closing of the power device, thereby controlling the motor in the electric drive system.

[0051] During the opening and closing process of the power device, switching loss will be generated. Switching loss is an important part of the total loss of the electric drive and has an important impact on the efficiency of the electric drive. From the perspective of electric drive efficiency, the faster the switching speed, the better. However, during the switching process of the power device, due to the reverse recovery effect of the diode and the stray inductance on the DC bus, switching voltage stress and switching current stress will be generated in the power device. The faster the switching speed of the power device, the greater the switching voltage stress and switching current stress. Excessive switching voltage stress and switching current stress may cause damage to the power device and reduce the safety of the power device. Therefore, when controlling the switching speed, it is necessary to comprehensively consider the switching loss and safety, so as to minimize the switching loss while ensuring the safety of the device under the worst working conditions.

[0052] In the related art, the electric drive system adjusts the switching speed of the power device by adjusting the resistance value of the driving resistor of the power device. Therefore, the selection of the resistance value of the driving resistor should ensure the safety of the device during the switching process and ensure that the switching loss is as small as possible.

[0053] Figure 1 FIG. 2 shows a structural block diagram of an electric drive system provided by an embodiment of the present disclosure. Figure 1 As shown, the resistance value of the driving resistor is realized by turning on or off the metal oxide semiconductor (MOS) tube (i.e., T1 to Tn, B1 to Bn). The MCU controls the turning on and off of the MOS tube through an isolation signal. Each driving resistor corresponds to a MOS tube and an isolation channel.

[0054] Figure 2 FIG. 1 is a schematic diagram showing a flow chart of calibrating the resistance value of a driving resistor provided by an embodiment of the present disclosure. Figure 2 As shown, taking the turn-on process of an insulated gate bipolar transistor (IGBT) as an example, the steps for adjusting the gate resistance of the IGBT are as follows:

[0055] 1. Set the initial working condition and preset the initial value of the driving resistance under the initial working condition;

[0056] 2. Perform a double pulse test to determine whether the IGBT exceeds the safe operating area (SOA) under the current initial value of the driving resistance; if so, increase the driving resistance value and re-perform the double pulse test to determine whether it exceeds the IGBT working SOA; if not, determine whether it meets the IGBT derating design standard. If so, use the current driving resistance value as the optimal driving resistance value under the current working condition; if not, reduce the driving resistance value and re-perform the double pulse test until it is reduced to the minimum value that meets the IGBT derating design standard, and use the minimum value as the optimal driving resistance value;

[0057] 3. Adjust the working conditions and repeat steps 1 to 2 until the calibration of the optimal driving resistance value for all working conditions is completed;

[0058] 4. Through the previous calibration, the optimal driving resistance value under each working condition can be obtained, which can be formed into a table or fitted into a curve. During the operation of the motor controller, the driving resistance value can be adjusted in real time according to the corresponding relationship between the working condition and the optimal driving resistance value.

[0059] It should be noted that after the calibration is completed, the optimal driving resistance value under each working condition is determined and cannot be changed. Since the switching speed of the power device is affected by the working conditions of the electric drive (different DC voltage, switching current, device junction temperature), the switching voltage stress and switching current stress of the power device are different under different DC bus, driving current and device junction temperature. The fixed driving resistance cannot guarantee that the switching loss of the power device under different working conditions is optimal. Under the working conditions where the switching voltage stress and switching current stress are small, the control of the switching speed is too conservative, so the switching loss will be relatively large, which will undoubtedly increase the loss of the electric drive and reduce the overall efficiency of the electric drive.

[0060] In addition, the above scheme does not give a clear description of current detection. The traditional current detection scheme is to detect the three-phase current through a three-phase current sensor and calculate the amplitude of the three-phase current, that is, the maximum current. However, since the three-phase current is a sinusoidal quantity, the maximum current only occupies a very small part of the entire cycle. When the maximum value is used to switch the drive resistance value, the efficiency of the electric drive system is low, because the current most of the time except the maximum value can undoubtedly use a more appropriate drive resistance value to reduce losses. In addition, at the same time, the current size of each IGBT is different, and the efficiency of the electric drive system is also low when the same switching speed is used. Secondly, this scheme requires a lot of calibration work for working conditions, which is labor-intensive and costly.

[0061] In summary, the traditional switching speed control scheme has low control accuracy, poor control effect and high cost.

[0062] The present disclosure is described in detail below with reference to specific embodiments.

[0063] In the first embodiment, if Figure 3 As shown, Figure 3 A flow chart of a method for controlling the switching speed of a power device provided in an embodiment of the present disclosure is shown. The method can be implemented by a computer program and can be executed by a power device switching speed control apparatus.

[0064] Specifically, the power device switching speed control method includes:

[0065] S101, determining a switch voltage stress threshold corresponding to a power device;

[0066] According to some embodiments, power devices include but are not limited to bipolar junction transistors (Bipolar Junction Transistor, BJT), gate turn-off thyristors (GTO), insulated gate bipolar transistors (Insulated Gate Bipolar Transistor, IGBT), integrated gate commutated thyristors (Integrated Gate Commuted Transistor, IGCT) and metal-oxide-semiconductor field-effect transistors (Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET), etc.

[0067] In some embodiments, the switch voltage stress refers to a peak voltage when a power device is switched.

[0068] In some embodiments, the switch voltage stress threshold refers to a preset switch voltage stress value. Under the switch voltage stress threshold, the power device can ensure the safety of the power device under harsh working conditions. The switch voltage stress threshold does not specifically refer to a fixed threshold. For example, when the model of the power device changes, the switch voltage stress threshold may change.

[0069] It is easy to understand that when the power device switching speed control apparatus executes the power device switching speed control method, the power device switching speed control apparatus can determine the switching voltage stress threshold corresponding to the power device.

[0070] S102, detecting the switch voltage stress corresponding to the power device to obtain a switch voltage stress detection value;

[0071] According to some embodiments, the switch voltage stress detection value refers to the switch voltage stress value corresponding to the current power device. The switch voltage stress detection value may change with the change of the detection time point.

[0072] It is easy to understand that when the power device switching speed control device executes the power device switching speed control method, the power device switching speed control device can detect the switching voltage stress corresponding to the power device to obtain the switching voltage stress detection value.

[0073] S103, adjusting the switching speed of the power device according to the switch voltage stress threshold and the switch voltage stress detection value.

[0074] According to some embodiments, the switching speed refers to the speed at which a power device switches from an on state to an off state, or switches from an off state to an on state.

[0075] It is easy to understand that when the power device switching speed control device obtains the switching voltage stress threshold and the switching voltage stress detection value, the power device switching speed control device can adjust the switching speed of the power device according to the switching voltage stress threshold and the switching voltage stress detection value.

[0076] In summary, the method provided by the embodiment of the present disclosure determines the switch voltage stress threshold corresponding to the power device; detects the switch voltage stress corresponding to the power device to obtain the switch voltage stress detection value; and adjusts the switch speed of the power device according to the switch voltage stress threshold and the switch voltage stress detection value. Therefore, the switch speed of the power device is adjusted according to the switch voltage stress corresponding to the power device, and the switch speed is maximized on the basis of ensuring the switch voltage stress, which can minimize the switch loss of the power device at each switch, and can reduce the switch loss under the premise of ensuring the safety of the power device. Moreover, compared with the traditional switch speed control scheme, the control accuracy is high, the control effect is good, and the cost is low.

[0077] See also Figure 4 , Figure 4 A schematic flow chart of a method for controlling the switching speed of a power device provided by an embodiment of the present disclosure is shown. The method can be executed by a power device switching speed control device.

[0078] Specifically, the power device switching speed control method includes:

[0079] S201, determining a bus voltage and a withstand voltage corresponding to a power device;

[0080] According to some embodiments, the bus voltage refers to a power supply voltage input to a power device. For example, when the power device is an IGBT, the bus voltage is a voltage input to a collector of the IGBT.

[0081] In some embodiments, the withstand voltage refers to the highest voltage that a power device can withstand.

[0082] It is easy to understand that when the power device switching speed control apparatus executes the power device switching speed control method, the power device switching speed control apparatus can determine the bus voltage and the withstand voltage corresponding to the power device.

[0083] S202, determining a switch voltage stress threshold corresponding to the power device according to the bus voltage and the withstand voltage;

[0084] According to some embodiments, the difference between the bus voltage and the withstand voltage may be used as a switch voltage stress threshold ΔUdc corresponding to the power device.

[0085] It is easy to understand that when the bus voltage and the withstand voltage are obtained, the power device switching speed control device can determine the switching voltage stress threshold corresponding to the power device according to the bus voltage and the withstand voltage.

[0086] S203, detecting the inductor voltage of the sampling inductor to obtain an inductor voltage detection value;

[0087] According to some embodiments, the power device is connected in series with the sampling inductor L1. For example, when the power device is an IGBT, the sampling inductor L1 may be connected to the collector of the IGBT, or the sampling inductor L1 may be connected to the emitter of the IGBT.

[0088] In some embodiments, the inductor voltage detection value Usense refers to the currently detected voltage value of the sampled inductor L1.

[0089] It is easy to understand that when the power device switching speed control device executes the power device switching speed control method, the power device switching speed control device can detect the inductor voltage of the sampling inductor to obtain the inductor voltage detection value.

[0090] S204, determining a loop inductance value corresponding to the power device;

[0091] According to some embodiments, the loop inductance value L2 refers to the total loop inductance value of the loop in which the power device is connected in series with the sampling inductor L1, excluding the sampling inductance value L1 of the sampling inductor L1. The loop inductance value L2 is a fixed value after the circuit design in which the power device is located is completed, and can be obtained by calculation or measurement.

[0092] S205, determining a switch voltage stress detection value corresponding to the power device according to the loop inductance value, the sampled inductance value corresponding to the sampled inductance, and the inductor voltage detection value;

[0093] According to some embodiments, based on the voltage-current relationship of the inductor element: U=L*di / dt, the relationship between the switch voltage stress detection value △Udc' corresponding to the power device and the inductor voltage detection value Usen corresponding to the sampling inductor L1 can be obtained:

[0094] △Udc'=(L2+L1) / L1*Usense

[0095] It is easy to understand that when the power device switching speed control device obtains the loop inductance value, the sampled inductance value corresponding to the sampling inductance and the inductor voltage detection value, the power device switching speed control device can substitute the loop inductance value, the sampled inductance value and the inductor voltage detection value into the relationship between the switch voltage stress detection value △Udc' corresponding to the above-mentioned power device and the inductor voltage detection value Usen corresponding to the sampling inductance L1 to obtain the switch voltage stress detection value △Udc'.

[0096] S206, using a control algorithm to determine a switch speed adjustment instruction according to a switch voltage stress threshold and a switch voltage stress detection value;

[0097] According to some embodiments, the control algorithm is used to accurately and quickly correct the controlled object. The control algorithm includes but is not limited to proportional integration (PI) control, fuzzy control, neural network control and other control algorithms.

[0098] For example, when the switch voltage stress detection value △Udc' is less than the switch voltage stress threshold △Udc, the switch speed adjustment instruction is used to instruct to increase the switch speed. Conversely, when the switch voltage stress detection value △Udc' is not less than the switch voltage stress threshold △Udc, the switch speed adjustment instruction is used to instruct to reduce the switch speed.

[0099] In some embodiments, the switching speed adjustment instruction is not only used to instruct to increase or decrease the switching speed, but also to indicate the specific value or ratio of increase or decrease when increasing or decreasing the switching speed. The specific value or ratio can be determined according to the difference between the switch voltage stress detection value ΔUdc' and the switch voltage stress threshold ΔUdc.

[0100] S207, adjusting the switching speed of the power device according to the switching speed adjustment instruction;

[0101] According to some embodiments, when adjusting the switching speed of a power device, the adjustment method includes but is not limited to adjusting the driving current corresponding to the power device, adjusting the resistance value of the driving resistor corresponding to the power device, etc.

[0102] In some embodiments, the driving current refers to the current input to the control terminal of the power device. For example, when the power device is an IGBT, the driving current refers to the current input to the gate of the IGBT.

[0103] In some embodiments, the driving resistance refers to a resistance connected to the control terminal of the power device. For example, when the power device is an IGBT, the driving current refers to a resistance connected to the gate of the IGBT.

[0104] According to some embodiments, in order to further improve the control effect, the switch voltage stress can be closed-loop controlled according to the switch voltage stress threshold and the switch voltage stress detection value; in the process of closed-loop control of the switch voltage stress, the switching speed of the power device is adjusted.

[0105] In some embodiments, Figure 5 FIG. 2 shows a closed-loop control block diagram of a power device switching speed provided by an embodiment of the present disclosure. Figure 5 As shown, the control algorithm used takes the difference between the switch voltage stress detection value △Udc' and the switch voltage stress threshold △Udc as zero as the control target, and executes steps S201 to S207 in a loop. Therefore, the switching speed of the power device can be adjusted in real time, the switching speed can be maximized on the basis of ensuring the switch voltage stress, and the switching loss of the power device at each switch can be minimized, so as to optimize the working efficiency of the power device.

[0106] In summary, the method provided by the embodiment of the present disclosure first determines the bus voltage and withstand voltage corresponding to the power device; determines the switch voltage stress threshold corresponding to the power device according to the bus voltage and the withstand voltage; therefore, the accuracy of determining the switch voltage stress threshold can be improved. Next, the inductor voltage of the sampling inductor is detected to obtain the inductor voltage detection value; the loop inductance value corresponding to the power device is determined; the switch voltage stress detection value corresponding to the power device is determined according to the loop inductance value, the sampling inductance value corresponding to the sampling inductor and the inductor voltage detection value; therefore, the accuracy of obtaining the switch voltage stress detection value can be improved. Finally, a control algorithm is used to determine the switch speed adjustment instruction according to the switch voltage stress threshold and the switch voltage stress detection value; according to the switch speed adjustment instruction, the switch speed of the power device is adjusted; therefore, compared with the traditional switch speed control scheme, the control accuracy and control effect when adjusting the switch speed of the power device can be improved, and the cost is relatively low. At the same time, the switching speed of the power device is adjusted according to the corresponding switching voltage stress of the power device. The switching speed is maximized on the basis of ensuring the switching voltage stress, which can minimize the switching loss of the power device during each switching and reduce the switching loss under the premise of ensuring the safety of the power device.

[0107] In the technical solution of the present disclosure, the collection, storage, use, processing, transmission, provision and disclosure of user personal information involved are in compliance with the provisions of relevant laws and regulations and do not violate public order and good morals.

[0108] The following are embodiments of the device disclosed herein, which can be used to execute the method embodiments disclosed herein. For details not disclosed in the device embodiments disclosed herein, please refer to the method embodiments disclosed herein.

[0109] See also Figure 6 , which shows a schematic diagram of the structure of a power device switching speed control device provided by an embodiment of the present disclosure. The power device switching speed control device can be implemented as all or part of the device through software, hardware or a combination of both. The power device switching speed control device is connected to the power device, and the power device switching speed control device includes a control module, a sampling module and a driving resistance module; wherein,

[0110] The sampling module is connected in series with the power device, and the sampling output end of the sampling module is connected to the input end of the control module, the output end of the control module is connected to the first end of the driving resistance module, and the second end of the driving resistance module is connected to the control end of the power device;

[0111] The control module is used to determine the switch voltage stress threshold corresponding to the power device; the control sampling module detects the switch voltage stress corresponding to the power device to obtain the switch voltage stress detection value; and the switch speed of the power device is adjusted according to the switch voltage stress threshold and the switch voltage stress detection value.

[0112] According to some embodiments, when the power device switching speed control apparatus executes the power device switching speed control method, the specific process is as shown in step S201 to step S207, which will not be described in detail here.

[0113] According to some embodiments, when the control module adjusts the switching speed of the power device, it includes but is not limited to adjusting the resistance value corresponding to the driving resistance module and adjusting the driving current.

[0114] In some embodiments, when the switching speed of the power device is adjusted by adjusting the driving current, the driving current can be adjusted by adjusting the driving voltage Vg input to the power device by the control module.

[0115] In some embodiments, when the switching speed of the power device is adjusted by adjusting the resistance value corresponding to the driving resistance module, the control module is also connected to the control end of the driving resistance module to adjust the resistance value corresponding to the driving resistance module. Figure 1 Adjustment method shown.

[0116] According to some embodiments, the driving resistor module includes an on-resistance submodule and an off-resistance submodule. The on-resistance submodule and the off-resistance submodule are connected in parallel. The on-resistance submodule is used when the power device is switched from the off state to the on state, and the off-resistance submodule is used when the power device is switched from the on state to the off state.

[0117] Optional, Figure 7 FIG. 2 is a schematic diagram showing a structure of a power device switching speed control device provided by an embodiment of the present disclosure. Figure 7 As shown, the sampling module includes a sampling inductor L1 and an operational amplifier OPA; wherein,

[0118] The sampling inductor L1 is connected in series with the power device S1, the first input terminal of the operational amplifier OPA is connected to the first terminal of the sampling inductor L1, the second input terminal of the operational amplifier OPA is connected to the second terminal of the sampling inductor L1, and the output terminal of the operational amplifier OPA is connected to the input terminal of the control module.

[0119] In summary, the device provided by the embodiment of the present disclosure includes a control module, a sampling module and a driving resistance module; the control module determines the switch voltage stress threshold corresponding to the power device; the sampling module is controlled to detect the switch voltage stress corresponding to the power device to obtain the switch voltage stress detection value; the switch speed of the power device is adjusted according to the switch voltage stress corresponding to the power device, and the switch speed is maximized on the basis of ensuring the switch voltage stress, which can minimize the switch loss of the power device at each switch, and can reduce the switch loss on the premise of ensuring the safety of the power device.

[0120] In the technical solution of the present disclosure, the collection, storage, use, processing, transmission, provision and disclosure of user personal information involved are in compliance with the provisions of relevant laws and regulations and do not violate public order and good morals.

[0121] According to an embodiment of the present disclosure, the present disclosure also provides an electric drive system.

[0122] Specifically, the electric drive system includes: at least one power device and at least one Figure 6 or Figure 7 The power device switching speed control device shown in the figure; wherein,

[0123] The power device switching speed control device and the power device are connected in a one-to-one correspondence.

[0124] In summary, the system provided by the embodiments of the present invention controls the switching speed of each power device in the system by controlling the switching speed of any power device according to the switching voltage stress corresponding to the power device. The switching speed can be maximized while ensuring the switching voltage stress, and the switching loss of any power device at each switch can be minimized. The switching loss of any power device can be reduced while ensuring the safety of any power device, thereby improving the overall efficiency of the electric drive system.

[0125] According to an embodiment of the present disclosure, the present disclosure also provides a power device switching speed control device, a readable storage medium and a computer program product.

[0126] Figure 8 A schematic block diagram of an example power device switching speed control apparatus 800 that can be used to implement an embodiment of the present disclosure is shown. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit implementations of the present disclosure described and / or claimed herein.

[0127] like Figure 8 As shown, the power device switching speed control device 800 includes a calculation unit 801, which can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) 802 or a computer program loaded from a storage unit 808 to a random access memory (RAM) 803. In the RAM 803, various programs and data required for the operation of the power device switching speed control device 800 can also be stored. The calculation unit 801, the ROM 802, and the RAM 803 are connected to each other through a bus 804. An input / output (I / O) interface 805 is also connected to the bus 804.

[0128] Multiple components in the power device switching speed control apparatus 800 are connected to the I / O interface 805, including: an input unit 806, such as a keyboard, a mouse, etc.; an output unit 807, such as various types of displays, speakers, etc.; a storage unit 808, such as a disk, an optical disk, etc.; and a communication unit 809, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 809 allows the power device switching speed control apparatus 800 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0129] The computing unit 801 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the computing unit 801 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, digital signal processors (DSPs), and any appropriate processors, controllers, microcontrollers, etc. The computing unit 801 performs the various methods and processes described above, such as a power device switching speed control method. For example, in some embodiments, the power device switching speed control method may be implemented as a computer software program, which is tangibly included in a machine-readable medium, such as a storage unit 808. In some embodiments, part or all of the computer program may be loaded and / or installed on the power device switching speed control device 800 via the ROM 802 and / or the communication unit 809. When the computer program is loaded into the RAM 803 and executed by the computing unit 801, one or more steps of the power device switching speed control method described above may be performed. Alternatively, in other embodiments, the calculation unit 801 may be configured to execute the power device switching speed control method in any other appropriate manner (for example, by means of firmware).

[0130] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0131] The program code for implementing the method of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that the program code, when executed by the processor or controller, enables the functions / operations specified in the flow chart and / or block diagram to be implemented. The program code may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0132] In the context of the present disclosure, a machine-readable medium may be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or equipment. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or equipment, or any suitable combination of the foregoing. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0133] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user can provide input to the computer. Other types of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0134] The systems and techniques described herein can be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), the Internet, and a blockchain network.

[0135] A computer system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The relationship between the client and the server is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services ("Virtual Private Server", or "VPS" for short). The server may also be a server of a distributed system, or a server combined with a blockchain.

[0136] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps recorded in this disclosure can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solutions disclosed in this disclosure can be achieved, and this document does not limit this.

[0137] The above specific implementations do not constitute a limitation on the protection scope of the present disclosure. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A method for controlling the switching speed of a power device, characterized in that: include: Determining a switch voltage stress threshold corresponding to a power device, comprising: determining a bus voltage and a withstand voltage corresponding to the power device; determining a switch voltage stress threshold corresponding to the power device according to the bus voltage and the withstand voltage; Detecting the switch voltage stress corresponding to the power device to obtain a switch voltage stress detection value, including: detecting the inductor voltage of a sampling inductor to obtain an inductor voltage detection value; determining a loop inductance value corresponding to the power device; determining the switch voltage stress detection value corresponding to the power device according to the loop inductance value, the sampling inductance value corresponding to the sampling inductor, and the inductor voltage detection value, wherein the power device is connected in series with the sampling inductor; The switching speed of the power device is adjusted according to the switching voltage stress threshold and the switching voltage stress detection value.

2. The method according to claim 1, characterized in that: The adjusting the switching speed of the power device according to the switch voltage stress threshold and the switch voltage stress detection value includes: Determining a switch speed adjustment instruction according to the switch voltage stress threshold and the switch voltage stress detection value using a control algorithm; The switching speed of the power device is adjusted according to the switching speed adjustment instruction.

3. The method according to claim 1, characterized in that The adjusting the switching speed of the power device includes: The driving current or the resistance value of the driving resistor corresponding to the power device is adjusted to adjust the switching speed of the power device, wherein the driving current refers to the current input to the control end of the power device, and the driving resistor refers to the resistor connected to the control end of the power device.

4. The method according to claim 1, characterized in that The adjusting the switching speed of the power device according to the switch voltage stress threshold and the switch voltage stress detection value includes: performing closed-loop control on the switch voltage stress according to the switch voltage stress threshold and the switch voltage stress detection value; In the process of performing closed-loop control on the switch voltage stress, the switching speed of the power device is adjusted.

5. A power device switching speed control device, characterized in that: The power device switching speed control device is connected to the power device, and the power device switching speed control device includes a control module, a sampling module and a driving resistance module; wherein, The sampling module is connected in series with the power device, and the sampling output end of the sampling module is connected to the input end of the control module, the output end of the control module is connected to the first end of the driving resistance module, and the second end of the driving resistance module is connected to the control end of the power device; The control module is used to determine the switch voltage stress threshold corresponding to the power device, including determining the bus voltage and the withstand voltage corresponding to the power device, and determining the switch voltage stress threshold corresponding to the power device according to the bus voltage and the withstand voltage; controlling the sampling module to detect the switch voltage stress corresponding to the power device to obtain a switch voltage stress detection value, including detecting the inductor voltage of the sampling inductor to obtain an inductor voltage detection value, determining the loop inductance value corresponding to the power device, and determining the switch voltage stress detection value corresponding to the power device according to the loop inductance value, the sampling inductance value corresponding to the sampling inductor and the inductor voltage detection value, wherein the power device is connected in series with the sampling inductor; and adjusting the switching speed of the power device according to the switch voltage stress threshold and the switch voltage stress detection value.

6. The device according to claim 5, characterized in that The sampling module includes a sampling inductor and an operational amplifier; wherein, The sampling inductor is connected in series with the power device, the first input terminal of the operational amplifier is connected to the first terminal of the sampling inductor, the second input terminal of the operational amplifier is connected to the second terminal of the sampling inductor, and the output terminal of the operational amplifier is connected to the input terminal of the control module.

7. The device according to claim 5, characterized in that The control module is also connected to the control end of the driving resistance module, and is used to adjust the resistance value corresponding to the driving resistance module.

8. An electric drive system, characterized in that: include: At least one power device and at least one power device switching speed control device as claimed in any one of claims 5 to 7; wherein, The power device switching speed control device is connected to the power devices in a one-to-one correspondence.

9. A power device switching speed control device, comprising: at least one processor; as well as a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1 to 4.

10. A non-transitory computer-readable storage medium storing computer instructions, wherein: The computer instructions are used to cause the computer to execute the method according to any one of claims 1 to 4.

Images