Method for acquiring inductive current of three-phase inverter circuit, electronic equipment and medium

Abstract

The invention relates to the technical field of three-phase inverter circuits, and provides a method for acquiring inductive current of a three-phase inverter circuit, a device for acquiring the inductive current of the three-phase inverter circuit, electronic equipment and a computer readable storage medium. The method for acquiring the inductive current of the three-phase inverter circuit comprises the following steps: generating a reference sampling trigger signal in response to a preset operation of sampling the inductive current, generating a loop interrupt signal based on the reference sampling trigger signal according to a preset interrupt signal generation strategy, and generating a loop interrupt signal according to the loop interrupt signal; due to the fact that the loop interruption signal can guarantee that the obtaining operation of the three-phase inductance current value is not interfered by other tasks, the loop interruption signal can be utilized to trigger loop interruption, and then the three-phase inductance current value of the three-phase inverter circuit is obtained in the loop interruption process. Time sequence errors or time interval errors do not exist among the obtained three-phase inductive current values, and the consistency of the obtaining moments of the three-phase inductive current is ensured.

Description

Technical Field

[0001] The present application belongs to the technical field of three-phase inverter circuits, and in particular relates to a method for obtaining the inductor current of a three-phase inverter circuit, a device for obtaining the inductor current of a three-phase inverter circuit, an electronic device, and a computer-readable storage medium. Background Art

[0002] Three-phase inverter circuits are widely used in the energy sector. For example, they can be installed in inverters and power conversion systems (PCSs). Whether in an inverter or a power conversion system, the three-phase inverter circuit is the core circuit for AC-DC conversion of electrical energy.

[0003] However, in practice, the inductor current of a three-phase inverter circuit is the basis for various power control functions, and its instantaneous value is strongly correlated with the operating state and control parameters of the three-phase inverter circuit. Therefore, even if the operating state of the three-phase inverter circuit remains unchanged, the inductor current measured at adjacent moments may vary significantly. Summary of the Invention

[0004] The purpose of this application is to provide a method for obtaining the inductor current of a three-phase inverter circuit, an apparatus for obtaining the inductor current of a three-phase inverter circuit, an electronic device and a computer-readable storage medium, aiming to provide a solution for obtaining the inductor current of a three-phase inverter circuit with higher accuracy and lower error.

[0005] A first aspect of an embodiment of the present application provides a method for obtaining an inductor current of a three-phase inverter circuit, comprising:

[0006] In response to a preset operation of sampling the inductor current, a reference sampling trigger signal is generated; wherein the reference sampling trigger signal is used to indicate a sampling timing of the three-phase inductor current of the three-phase inverter circuit;

[0007] Generate a loop interrupt signal based on a reference sampling trigger signal according to a preset interrupt signal generation strategy;

[0008] The loop interruption is triggered according to the loop interruption signal, and the three-phase inductor current values ​​of the three-phase inverter circuit are acquired in the loop interruption interval to obtain the three-phase inductor current values.

[0009] A second aspect of an embodiment of the present application provides a device for obtaining an inductor current of a three-phase inverter circuit, comprising:

[0010] A trigger signal generating unit, configured to generate a reference sampling trigger signal in response to a preset operation of sampling the inductor current; wherein the reference sampling trigger signal is used to indicate a sampling timing of the three-phase inductor current of the three-phase inverter circuit;

[0011] An interrupt signal generating unit, configured to generate a loop interrupt signal based on a reference sampling trigger signal according to a preset interrupt signal generating strategy;

[0012] The acquisition unit is used to trigger the loop interruption according to the loop interruption signal, and acquire the three-phase inductor current values ​​of the three-phase inverter circuit in the loop interruption interval to obtain the three-phase inductor current values.

[0013] A third aspect of an embodiment of the present application provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the electronic device. When the processor executes the computer program, the steps of the method for obtaining the inductor current of a three-phase inverter circuit provided in the first aspect are implemented.

[0014] A fourth aspect of an embodiment of the present application provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it implements the steps of the method for obtaining the inductor current of a three-phase inverter circuit provided in the first aspect above.

[0015] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0016] The above-mentioned method for acquiring the inductor current of a three-phase inverter circuit generates a reference sampling trigger signal in response to a preset operation for sampling the inductor current. Since the reference sampling trigger signal is used to indicate the sampling timing of the three-phase inductor current of the three-phase inverter circuit, the three-phase inductor current can be sampled at the same time according to the reference sampling trigger signal. According to a preset interrupt signal generation strategy, a loop interrupt signal is generated based on the reference sampling trigger signal. Because the loop interrupt signal can ensure that the acquisition operation of the three-phase inductor current value is not interfered with by other tasks, the loop interrupt signal can be used to trigger a loop interrupt, thereby acquiring the three-phase inductor current values ​​of the three-phase inverter circuit during the loop interruption interval. This ensures that there is no timing error or time interval error between the obtained three-phase inductor current values, ensuring the consistency of the acquisition time of the three-phase inductor current, thereby providing a solution for acquiring the inductor current of a three-phase inverter circuit with higher accuracy and lower error. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of an application scenario of a method for obtaining an inductor current of a three-phase inverter circuit provided in an embodiment of the present application;

[0018] Figure 2 A flowchart of a method for obtaining the inductor current of a three-phase inverter circuit provided in an embodiment of the present application;

[0019] Figure 3 The generation principle of the reference sampling trigger signal in the embodiment of the present application is shown as follows: Figure 1 ;

[0020] Figure 4 The generation principle of the reference sampling trigger signal in the embodiment of the present application is shown as follows: Figure 2 ;

[0021] Figure 5 A flowchart of a method for obtaining an inductor current of a three-phase inverter circuit provided in another embodiment of the present application;

[0022] Figure 6 A flowchart of a method for obtaining an inductor current of a three-phase inverter circuit provided in yet another embodiment of the present application;

[0023] Figure 7 This is a schematic diagram of a driving sampling signal in an embodiment of the present application;

[0024] Figure 8 A schematic diagram of the structure of a device for obtaining the inductor current of a three-phase inverter circuit provided in an embodiment of the present application;

[0025] Figure 9 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0026] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, this application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0027] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0028] For example, three-phase inverter circuits are widely used in the energy sector. For example, they can be installed in inverters, power conversion systems (PCSs), and other devices. Whether in an inverter or a power conversion system, the three-phase inverter circuit is the core circuit for AC-DC conversion of electrical energy.

[0029] However, in practice, the inductor current of a three-phase inverter circuit is the basis for various power control functions, and its instantaneous value is strongly correlated with the operating state and control parameters of the three-phase inverter circuit. Therefore, even if the operating state of the three-phase inverter circuit remains unchanged, the inductor current measured at adjacent moments may vary significantly.

[0030] For example, the three-phase inverter circuit in the PCS includes three half-bridge circuits, and the driving signal of each half-bridge circuit is different. The three-phase inductor currents are also different at the same time. If the inductor current of one phase is obtained at the first moment and the inductor currents of the other two phases are obtained at the second moment, the timing of obtaining the three-phase inductor currents is inconsistent, and the PCS cannot perform corresponding control operations based on the three-phase inductor currents.

[0031] To address the above-mentioned technical problems, this embodiment provides a method for acquiring the inductor current of a three-phase inverter circuit. In response to a preset operation for sampling the inductor current, a reference sampling trigger signal is generated. Since the reference sampling trigger signal indicates the sampling timing of the three-phase inductor current of the three-phase inverter circuit, the three-phase inductor current can be sampled at the same time according to the reference sampling trigger signal. A loop interrupt signal is generated based on the reference sampling trigger signal according to a preset interrupt signal generation strategy. Because the loop interrupt signal ensures that the acquisition operation of the three-phase inductor current values ​​is not interfered with by other tasks, the loop interrupt signal can be used to trigger a loop interrupt, thereby acquiring the three-phase inductor current values ​​of the three-phase inverter circuit during the loop interruption interval. This ensures that there is no timing error or time interval error between the obtained three-phase inductor current values, ensuring consistency in the acquisition time of the three-phase inductor current, thereby providing a solution for acquiring the inductor current of a three-phase inverter circuit with higher accuracy and lower error.

[0032] This embodiment provides a method for obtaining the inductor current of a three-phase inverter circuit, which is executed by the three-phase inverter circuit, specifically a processor, a control chip, etc. in the three-phase inverter circuit.

[0033] In practical applications, the three-phase inverter circuit can be configured in an inverter, energy storage converter, energy storage system, or vehicle. The energy storage system can be one that connects energy storage equipment to the power grid, and the vehicle can be a new energy vehicle, such as a pure electric vehicle or a hybrid electric vehicle, without limitation.

[0034] The following describes in detail a method for obtaining the inductor current of a three-phase inverter circuit provided by this embodiment through a specific implementation manner, taking a control unit in a three-phase inverter circuit as an example.

[0035] Figure 1 FIG2 shows a schematic diagram of an application scenario of a method for obtaining the inductor current of a three-phase inverter circuit provided by an embodiment of the present application. It is easy to understand that Figure 1 In the example shown, a three-phase inverter circuit is configured with an inverter circuit and a control unit. In practical applications, the inverter circuit can be a three-phase three-bridge circuit or a three-phase four-bridge circuit. This example is only used to illustrate sampling three-phase inductor currents and does not limit the specific implementation of the inverter circuit.

[0036] exist Figure 1 In the example shown, the inverter circuit outputs three-phase AC power through the first inductor L1, the second inductor L2, and the third inductor L3. When sampling the three-phase inductor current, at least an ADC sampling circuit (not shown in the figure) can be used to sample the inductor current of the first inductor L1, the second inductor L2, and the third inductor L3. It is easy to understand that, in addition to the Hall sensor in the ADC sampling circuit, other components in the ADC sampling circuit can be integrated into the control unit. Here, the control unit may include a processor MCU and an ADC sampling circuit (not shown in the figure).

[0037] exist Figure 1 In the example, the control unit is connected to the inverter circuit and can be used to control the operation of the inverter circuit. The three Hall sensors (D1, D2, and D3) of the ADC sampling circuit sample the inductor currents in the first inductor L1, the second inductor L2, and the third inductor L3, respectively, to obtain the three-phase inductor current values. The MCU in the control unit is connected to the ADC sampling circuit to obtain the three-phase inductor current values ​​from the ADC sampling circuit.

[0038] The following further describes the method for obtaining the inductor current of a three-phase inverter circuit provided in an embodiment of the present application, taking the processor MCU in the control unit as the execution body.

[0039] Figure 2 FIG1 shows a flow chart of a method for obtaining the inductor current of a three-phase inverter circuit provided by an embodiment of the present application. Figure 2 As shown, the method for obtaining the inductor current of the three-phase inverter circuit includes the following steps:

[0040] 110 : In response to a preset operation of sampling the inductor current, generate a reference sampling trigger signal.

[0041] In 110 , the reference sampling trigger signal is used to indicate a sampling timing of the three-phase inductor current of the three-phase inverter circuit.

[0042] In this embodiment, the preset operation of sampling the inductor current generally refers to a trigger condition for obtaining the inductor current that is pre-configured in the three-phase inverter circuit.

[0043] It is easy to understand that during the operation of the three-phase inverter circuit, it is necessary to continuously adjust its control strategy according to the output three-phase alternating current.

[0044] For example, a current loop is configured in a three-phase inverter circuit, and closed-loop control can be achieved by sampling the three-phase inductor current and then inputting the three-phase inductor current into the current loop.

[0045] For another example, a three-phase inverter circuit is connected between the energy storage device and the power grid. A control strategy for charging and discharging the energy storage device is configured in the three-phase inverter circuit. The charging and discharging power of the energy storage device can be accurately controlled according to the sampled three-phase inductor current, ensuring efficient energy conversion between the energy storage device and the power grid.

[0046] For example, the three-phase inverter circuit can also obtain the inductor current, identify the harmonic components, adjust the PWM modulation strategy (such as the harmonic compensation algorithm), suppress the low-order harmonics in the output current, or compensate for the unbalanced components through the control algorithm to avoid the reduction of power exchange efficiency.

[0047] It is easy to understand that, in a specific implementation, corresponding inductor current sampling conditions can be set as the preset operation according to the usage scenario or control requirements of the three-phase inverter circuit. In all embodiments of the present application, the preset operation of sampling the inductor current can specifically refer to an operation of adjusting the operating state or control parameters of the three-phase inverter circuit based on the inductor current.

[0048] Exemplarily, the preset operation may be when the three-phase inverter circuit adjusts the driving signal of the three-phase inverter circuit according to the preset control strategy, and / or after the three-phase inverter circuit adjusts the driving signal of the three-phase inverter circuit.

[0049] In some embodiments, the preset operation may also be a charging instruction instructing the three-phase inverter circuit to use the power provided by the grid to charge the energy storage device, or a discharging instruction instructing the three-phase inverter circuit to use the power of the energy storage device to supply power to the grid.

[0050] It is easy to understand that since the reference sampling trigger signal is used to indicate the sampling timing of the three-phase inductor current of the three-phase inverter circuit, the three-phase inductor current can be sampled simultaneously under the action of the reference sampling trigger signal, that is, the reference sampling trigger signal specifically indicates the sampling moment of the three-phase inductor current.

[0051] In a specific implementation, the reference sampling trigger signal can be a level signal with a valid rising edge. The MCU in the three-phase inverter circuit generates the reference sampling trigger signal and sends it to the corresponding ADC sampling circuit. The ADC sampling circuit responds to the rising edge of the reference sampling trigger signal to sample the inductor current, and then feeds the sampled three-phase inductor current value back to the MCU.

[0052] As an embodiment, step 110 may specifically include:

[0053] A triangular carrier signal of a three-phase inverter circuit is obtained, and a reference sampling trigger signal is generated according to the triangular carrier signal, wherein the flipping moment of the triangular carrier signal corresponds to the triggering moment of the reference sampling trigger signal.

[0054] In this embodiment, the triangular carrier signal can be understood as a modulated reference signal generated by a three-phase inverter circuit. Specifically, the triangular carrier signal can be a periodically rising / falling triangular waveform signal. The reference sampling trigger signal corresponds to the flipping moment of the triangular carrier signal. That is, the effective edge of the reference sampling trigger signal corresponds to the flipping moment (the rising peak and falling minimum) of the triangular carrier signal.

[0055] For example, Figure 3 The schematic diagram shows the generation principle of the reference sampling trigger signal in the embodiment of the present application. Figure 1 .like Figure 3 As shown, point A1 and point A3 in the triangular carrier signal are both the highest rising point moments of the triangular carrier signal, that is, the moment when the trend turns from the highest rising point to a downward trend. Point A2 is between point A1 and point A3, and point A2 is the lowest falling point moment of the triangular carrier signal, that is, the moment when the trend turns from the lowest falling point to an upward trend. Taking the rising edge validity of the reference sampling trigger signal as an example, when generating the reference sampling trigger signal based on the triangular carrier signal, a rising edge can be generated corresponding to each rising highest point moment and each falling lowest point moment of the triangular carrier signal. Of course, in actual implementation, the reference sampling trigger signal can also be a level signal with a falling edge validity. Accordingly, when generating the reference sampling trigger signal based on the triangular carrier signal, a falling edge can be generated corresponding to each rising highest point moment and each falling lowest point moment of the triangular carrier signal (not shown in the figure).

[0056] In a specific implementation, the triangular carrier signal can be a high-frequency clock signal generated by a digital controller or a dedicated pulse width modulation chip. Here, the triangular carrier signal can also be driven by a high-frequency clock signal (such as 10kHz to 20kHz) to drive a counter, periodically generating a linearly rising / falling triangular waveform, and serving as a modulation reference signal. Accordingly, when generating a reference sampling trigger signal based on the triangular carrier signal, the MCU can determine the corresponding flip time based on the triangular carrier signal generated by the counter, and then generate the reference sampling trigger signal.

[0057] It should be noted that, because the triangular carrier signal forms the basis of the sinusoidal pulse width modulation (SPWM) signal in a three-phase inverter circuit, it generates a PWM signal with a variable duty cycle by comparing it with the modulating wave (such as a sine wave or a modified waveform with harmonic compensation), which is used to drive the three-phase bridge arm circuit to generate three-phase AC power. Therefore, the triangular carrier signal carries the basic characteristics of the PWM signal. Specifically, the flip-flop moment of the triangular carrier signal can represent the midpoint of the PWM signal's pulse width and the midpoint of the interval between adjacent pulse widths. Based on this, a reference sampling trigger signal can be quickly generated to indicate the sampling timing of the three-phase inductor current.

[0058] As another embodiment, the three-phase inverter circuit includes a three-phase bridge arm circuit. Accordingly, step 110 may specifically include:

[0059] Obtain a PWM signal corresponding to a first bridge arm in a three-phase bridge arm circuit. The first bridge arm is any bridge arm in the three-phase bridge arm circuit. Determine a first midpoint time of a first state level and a second midpoint time of a second state level in the PWM signal. Generate a reference sampling trigger signal based on the first midpoint time and the second midpoint time; the triggering time of the reference sampling trigger signal corresponds to the first midpoint time and the second midpoint time.

[0060] In this embodiment, since the triangular carrier signal serves as the basis for a sinusoidal pulse width modulation (SPWM) signal in a three-phase inverter circuit, a PWM signal with a variable duty cycle is generated by comparing it with a modulated wave (e.g., a sine wave or a modified waveform including harmonic compensation) to drive the three-phase bridge arm circuit to generate three-phase AC power. Therefore, when obtaining the PWM signal corresponding to any one of the three-phase bridge arm circuits, three sets of PWM signals corresponding to the three-phase bridge arm circuit can be generated from the triangular carrier signal using existing PWM pulse generation methods. Based on this, the PWM signal corresponding to any one of the three bridge arm circuits can be selected from the three sets of PWM signals as a reference to generate a reference sampling trigger signal.

[0061] For example, Figure 4 The schematic diagram shows the generation principle of the reference sampling trigger signal in the embodiment of the present application. Figure 2 .like Figure 4 As shown, points A1' and A3' in the triangular carrier signal are both the lowest points of the triangular carrier signal, that is, the moment when the trend reverses from the lowest point of the decline to the rising trend. Point A2' is between points A1' and A3' and is the highest point of the triangular carrier signal, that is, the moment when the trend reverses from the highest point of the rise to the falling trend.

[0062] As an example, in Figure 4 In the example, the first state level of the PWM signal can be a high level. Accordingly, the first midpoint of the first state level of the PWM signal is the midpoint of the high level of the PWM signal, such as point P1. The second state level of the PWM signal can be a low level. Accordingly, the second midpoint of the second state level of the PWM signal is the midpoint of the low level of the PWM signal, such as point P2. Based on this, the reference sampling trigger signal is generated based on the first midpoint and the second midpoint. The valid edge of the reference sampling trigger signal can be generated at both the first midpoint and the second midpoint. That is, the rising edge triggering time of the reference sampling trigger signal corresponds to the first midpoint and the second midpoint.

[0063] 120: Generate a loop interrupt signal based on the reference sampling trigger signal according to a preset interrupt signal generation strategy.

[0064] In 120, the preset interrupt signal generation strategy is used to describe the manner or method of generating the loop interrupt signal based on the reference sampling trigger signal. In specific implementation, it can be set according to the sampling frequency or the maximum sampling time of the ADC sampling circuit in the three-phase inverter circuit.

[0065] For example, when sampling the three-phase inductor current of a three-phase inverter circuit, this can be achieved through an ADC sampling circuit. Due to certain device errors or sampling errors in the ADC sampling circuit, there may be deviations in the sampling frequency or synchronization between different ADC sampling circuits. Therefore, in actual implementation, the sampling durations of different sampling branches of the ADC sampling circuit can be compared, and the value with the longest unit sampling duration can be set as the extension time. Based on this extension time configuration, a corresponding preset interrupt signal generation strategy can be derived.

[0066] As an embodiment, the preset interrupt signal generation strategy includes a minimum redundancy time. Accordingly, step 120 specifically includes:

[0067] Determine the pulse width end point of the reference sampling trigger signal. Generate a loop interruption signal based on the pulse width end point and the minimum redundancy time. The pulse width start point of the loop interruption signal and the pulse width end point of the reference sampling trigger signal are separated by at least the minimum redundancy time.

[0068] In this embodiment, the minimum redundancy time refers to the minimum time required to ensure that each sampling branch in the ADC sampling circuit samples the inductor current. It is understood that in all embodiments of the present application, since the ADC sampling circuit has a high sampling frequency, multiple samples of the inductor current can be taken in a short period of time. Therefore, in the reference sampling trigger signal, after the active edge is triggered, a minimum redundancy time interval can be maintained to ensure that all ADC sampling circuits can sample the existing electrical signal. Based on this, when the reference sampling trigger signal has been generated, the pulse width end point of the reference sampling trigger signal can be obtained and superimposed with the minimum redundancy time to determine the pulse width starting point of the loop interrupt signal. The pulse width end point of the loop interrupt signal is then determined based on the expected interruption duration of the loop interrupt signal, thereby generating the loop interrupt signal. Here, the loop interrupt signal can be triggered after the reference ADC sampling circuit responds to the reference sampling trigger signal. Since other tasks in the three-phase inverter circuit will not be responded to when the loop interrupt signal triggers the loop interrupt, reading the current value of the ADC sampling circuit at this time can avoid noise interference in the read value.

[0069] 130: triggering a loop interruption according to the loop interruption signal, and obtaining three-phase inductor current values ​​of the three-phase inverter circuit during the loop interruption process.

[0070] In 130, the loop interruption signal is used to describe the timing of triggering a loop interruption. Here, the loop interruption signal can be a periodic signal, that is, the loop interruption signal can include multiple timings for triggering a loop interruption. In a specific implementation, the specific duration of the loop interruption signal or the specific number of times the loop interruption is triggered can correspond to the requirements of inductor current sampling. In other words, the specific duration of the loop interruption signal or the specific number of times the loop interruption is triggered can be set based on the number of times and periodicity of inductor current sampling.

[0071] In this embodiment, when a loop interrupt is triggered by a loop interrupt signal, the loop interrupt may be the highest-priority interrupt event, so no other interrupt events are responded to during the loop interruption. Therefore, obtaining the three-phase inductor current values ​​of the three-phase inverter circuit during the loop interruption ensures that the obtained three-phase inductor current values ​​are the three-phase inductor current values ​​at the same moment. In a specific implementation, the MCU in the three-phase inverter circuit triggers the loop interruption by responding to the loop interruption signal, and obtains the three-phase inductor current values ​​of the three-phase inverter circuit during the loop interruption.

[0072] The above scheme generates a loop interruption signal based on a reference sampling trigger signal in accordance with a preset interruption signal generation strategy, triggers a loop interruption by means of the loop interruption signal, and obtains the three-phase inductor current values ​​of the three-phase inverter circuit during the loop interruption process, thereby ensuring that the acquisition operation of the three-phase inductor current values ​​is not interfered with by other tasks, and further obtaining the three-phase inductor current values ​​of the three-phase inverter circuit during the loop interruption process, so that there will be no timing error or time interval error between the obtained three-phase inductor current values, thereby ensuring the consistency of the acquisition time of the three-phase inductor current, thereby providing a scheme for obtaining the inductor current of the three-phase inverter circuit with higher accuracy and lower error.

[0073] Figure 5 FIG1 shows a flow chart of a method for obtaining the inductor current of a three-phase inverter circuit provided by another embodiment of the present application. Figure 5 As shown, Figure 1 The difference between the embodiments is that the method for obtaining the inductor current of a three-phase inverter circuit provided in this embodiment further includes steps 210 to 220 after step 110. In this embodiment, the three-phase inverter circuit includes a three-phase bridge arm circuit and an ADC sampling circuit correspondingly connected to the three-phase bridge arm circuit. The ADC sampling circuit includes a Hall sensor. Specifically:

[0074] 210: According to the reference sampling trigger signal, the inductor current of the three-phase bridge arm circuit is sampled through the Hall sensor in the ADC sampling circuit to obtain three sets of current sample data; wherein the sampling time of the three sets of current sample data corresponds to the triggering time of the reference sampling trigger signal.

[0075] 220: Calculate the three-phase inductor current values ​​using the three sets of current sample data.

[0076] Combine Figure 1 In this embodiment, the ADC sampling circuit includes a Hall sensor. Accordingly, the ADC sampling circuit may include three Hall sensors, namely, a Hall sensor D1, a Hall sensor D2, and a Hall sensor D3. Figure 1 In the embodiment, the Hall sensor D1, the Hall sensor D2 and the Hall sensor D3 are respectively arranged in the branches of the three-phase AC inductor A, B and C.

[0077] In this embodiment, the MCU in the control unit controls the ADC sampling circuit based on the reference sampling trigger signal to sample the three inductor currents via Hall sensors D1, D2, and D3. Based on the sampled electrical signals, the ADC sampling circuit generates three sets of current sample data and sends them to the MCU. The MCU then uses these three sets of current sample data to calculate the three-phase inductor current values.

[0078] exist Figure 4 In the example, taking the inductor current of any phase as an example, when the PWM signal is high, the inductor current increases upward, such as when the inductor current changes from point I1 to point I2. When the PWM signal is low, the inductor current decreases downward, such as when the inductor current changes from point I2 to point I1'. Based on this, the rising edge level of the PWM signal can be triggered when the triangular carrier signal passes through 0, that is, point AX, and the falling edge level of the PWM signal can be triggered half a cycle later, that is, point AY. At this time, the flipping moment of the triangular carrier signal (point A1 and point A2) must correspond to the rising midpoint I and the falling midpoint I' of the inductor current. The reference sampling trigger signal is used to indicate the sampling timing of the three-phase inductor current of the three-phase inverter circuit. That is, according to the reference sampling trigger signal, the Hall sensor in the ADC sampling circuit samples the inductor current to obtain current sample data corresponding to the rising midpoint I and the falling midpoint I' of the inductor current.

[0079] As an embodiment, step 220 may specifically include: calculating an average value of the current sample data to obtain the inductor current value.

[0080] Combine Figure 4 In the example shown, the reference sampling trigger signal corresponds to the midpoint of the inductor current rise I and the midpoint of the inductor current fall I'. It can be seen that within a PWM signal cycle, the average value of the inductor current per unit time is Iavg*Ts=(Idc+Ipp*0.5)*Ts, where Ts is the cycle length of the PWM signal; Idc is the non-DC part; Ipp is the peak-to-peak value of the current; and the instantaneous value of the current midpoint is the average value Iinst(k)=Iavg. It is easy to understand that in order to represent the current value in different processes, Figure 4 In the example shown, the midpoint of the inductor current's rising edge is denoted by I, and the midpoint of the inductor current's falling edge is denoted by I'. In practice, the process for calculating the midpoint of the inductor current's rising edge, I, is the same as the process for calculating the midpoint of the inductor current's falling edge, I'. That is, for a rising edge, the sampling time is Iinst(k) = Iavg + Ipp * 0.5; for a falling edge, the sampling time is Iinst(k) = Iavg + Ipp * 0.5.

[0081] In the above scheme, the sampling time of the current sample data is aligned with the triggering time of the reference sampling trigger signal. Based on this, the Hall effect sensors in the ADC sampling circuits can sample the inductor current according to the reference sampling trigger signal to obtain current sample data. The inductor current values ​​can be calculated using the current sample data. Consequently, when step 130 is executed, the inductor current values ​​corresponding to the three ADC sampling circuits, i.e., the three-phase inductor current values, can be directly obtained.

[0082] Figure 6 FIG1 shows a flow chart of a method for obtaining the inductor current of an energy storage converter provided by another embodiment of the present application. Figure 6 As shown, Figure 2 The difference between the embodiments is that the method for obtaining the inductor current of a three-phase inverter circuit provided in this embodiment further includes steps 310 to 320 after step 130. In this embodiment, the three-phase inverter circuit includes a three-phase bridge arm circuit and a driving unit for driving the three-phase bridge arm circuit. Specifically:

[0083] 310: In response to a preset voltage regulation instruction, obtain a driving signal output by the driving unit to the three-phase bridge arm circuit.

[0084] In 310 , the preset voltage regulation instruction generally refers to an instruction for controlling the voltage level of the three-phase bridge arm circuit transmitting electric energy.

[0085] It is easy to understand that in the actual use of the energy storage converter, the output voltage of the three-phase inverter circuit can be adjusted by adjusting the working mode of the three-phase inverter circuit. Figure 1 Taking the application scenario diagram shown as an example, when a three-phase inverter circuit includes a three-phase bridge arm circuit, the three-phase bridge arm circuit is connected to an AC switch via a first inductor L1, a second inductor L2, and a third inductor L3, and is then connected to an AC source, such as a power grid, through the AC switch. Based on this, when exchanging electrical energy between a DC source and an AC source, the voltage of the exchanged electrical energy can be regulated by controlling the on-off frequency of the switches in each arm of the three-phase bridge arm circuit.

[0086] In a specific implementation, the three-phase bridge arm circuit is controlled by a drive unit. Here, the drive unit can be integrated in the control unit, or it can be a drive chip controlled by the control unit. When utilizing the power exchange between the DC source and the AC source, the control unit can trigger a preset voltage regulation instruction according to a preset working strategy, and then control the working mode of the three-phase bridge arm circuit by controlling the drive unit to output a corresponding drive signal, thereby realizing the voltage regulation operation. It is easy to understand that in all embodiments, since the three-phase inverter circuit can realize the power exchange between the DC source and the AC source, the voltage regulation operation for the three-phase inverter circuit can be to adjust the voltage of the power transmitted to the DC source, or to adjust the voltage of the power transmitted to the AC source, and there is no limitation here.

[0087] It should be noted that, considering that the control unit triggers or responds to a preset voltage regulation instruction, thereby controlling the drive unit to output a drive signal, and that the drive signal acts on the three-phase bridge arm circuit, there is a response time or response delay, and when the control unit controls the drive unit to output a drive signal, the control instruction / control signal output by the control unit to the drive unit cannot be directly used to generate a new reference sampling trigger signal. Based on this, when responding to the preset voltage regulation instruction, by obtaining the drive signal output by the drive unit to the three-phase bridge arm circuit, since the drive signal has a certain periodicity and has the natural conditions for generating a new reference sampling trigger signal, the step of generating a reference sampling trigger signal can be performed based on the drive signal, thereby obtaining a new reference sampling trigger signal.

[0088] In a specific implementation, the MCU in the control unit can respond to a preset voltage regulation instruction and then output a voltage regulation control instruction to the drive unit. The voltage regulation control instruction is at least used to indicate the voltage of the electric energy after voltage regulation. The drive unit can output a corresponding drive signal based on the voltage regulation control instruction. It is understandable that when the voltage regulation control of the three-phase bridge arm circuit is achieved through the drive signal, it is usually achieved by adjusting the high and low level duty cycle of the drive signal, that is, the drive signal has the characteristic of a constant cycle length.

[0089] As one possible implementation, when the MCU obtains the drive signal, the drive unit can specifically return period information of the drive signal to the MCU in response to the voltage regulation control instruction. The MCU can then generate a corresponding drive sampling signal based on the period information, and then obtain the drive signal based on the drive sampling signal. In this embodiment, the drive signal may include a PWM signal corresponding to the first bridge arm in the three-phase bridge arm circuit. Here, the first bridge arm can be any bridge arm in the three-phase bridge arm circuit.

[0090] It is easy to understand that in actual implementation, when responding to a preset voltage regulation instruction, there may be large differences in the waveforms of adjacent periods in the drive signal. Based on this, the drive signals of adjacent periods can be sampled according to the period information of the drive signal. By fitting the drive signals of adjacent periods, an adaptive reference sampling trigger signal can be generated even when there may be large differences in the waveforms.

[0091] For example, Figure 7 FIG. 1 shows a schematic diagram of a driving sampling signal in an embodiment of the present application. Figure 7 As shown, the period of the driving sampling signal is twice that of the driving signal, that is, within one period of the driving sampling signal, two adjacent groups of driving signals can be collected. For example, the first sampling channel and the second sampling channel can be used to sample the driving signal. Figure 7 In the embodiment, the drive sampling signal sequentially outputs a first level Tx1 and a second level Ty1 within a first period T1, wherein the first sampling channel samples the drive signal under the action of the first level Tx1, and the second sampling channel samples the drive signal under the action of the second level Ty1. Based on this, the first drive signal sample sampled by the first sampling channel can be fitted with the second drive signal sample sampled by the second sampling channel to obtain the corresponding drive signal. Here, in a specific implementation, the first drive signal sample sampled by the first sampling channel is fitted with the second drive signal sample sampled by the second sampling channel. Specifically, the duty cycle of the first drive signal sample can be averaged with the duty cycle of the second drive signal sample, or the high and low levels of the two can be averaged to obtain the corresponding drive signal.

[0092] 320 : Based on the driving signal, re-execute the step of generating a reference sampling trigger signal in response to a preset operation of sampling the inductor current.

[0093] In 320 , the step of generating a reference sampling trigger signal in response to the preset operation of sampling the inductor current is re-executed, that is, returning to step 110 .

[0094] In this embodiment, since the driving signal has a certain periodicity, a reference sampling trigger signal with periodicity can be generated based on the driving signal.

[0095] It is easy to understand that since the step of generating the reference sampling trigger signal in response to the preset operation of sampling the inductor current is re-executed, it can be regarded as returning to step 110. Therefore, when the driving signal is a PWM signal, when generating the reference trigger signal based on the driving signal, the same method as Figure 1 The same means of generating the reference sampling trigger signal in the embodiment is implemented.

[0096] For example, a PWM signal corresponding to a first bridge arm in a three-phase bridge arm circuit is obtained. The first bridge arm is any bridge arm in the three-phase bridge arm circuit. A first midpoint time of a first state level and a second midpoint time of a second state level in the PWM signal are determined. A reference sampling trigger signal is generated based on the first midpoint time and the second midpoint time; the triggering time of the reference sampling trigger signal corresponds to the first midpoint time and the second midpoint time.

[0097] The above scheme obtains the drive signal output by the drive unit to the three-phase bridge arm circuit in response to a preset voltage regulation instruction. Since the drive signal has a natural periodic characteristic, the step of generating a reference sampling trigger signal in response to the preset operation of sampling the inductor current can be re-executed based on the drive signal, and then a reference sampling trigger signal corresponding to the preset voltage regulation instruction is generated. The reference sampling trigger signal changes according to the change of the voltage regulation demand, so that the reference sampling trigger signal can follow the change of the operating condition of the three-phase inverter circuit, so that the generated reference sampling trigger signal can dynamically meet all the operating conditions of the three-phase inverter circuit, providing a scheme for obtaining the inductor current of the three-phase inverter circuit with a wider range of applications.

[0098] See also Figure 8 , Figure 8 The schematic diagram of the structure of a device for obtaining the inductor current of a three-phase inverter circuit provided by an embodiment of the present application is shown. In this embodiment, the device for obtaining the inductor current of a three-phase inverter circuit includes various units for performing Figure 1 Each step in the corresponding embodiment. Please refer to Figure 1 For the convenience of explanation, only the parts related to this embodiment are shown. Figure 8 The device for obtaining the inductor current of the three-phase inverter circuit includes: a trigger signal generating unit 801, an interrupt signal generating unit 802 and an obtaining unit 803. Specifically:

[0099] The trigger signal generating unit 801 is configured to generate a reference sampling trigger signal in response to a preset operation of sampling the inductor current; wherein the reference sampling trigger signal is configured to indicate a timing for sampling the three-phase inductor current of the three-phase inverter circuit.

[0100] The interrupt signal generating unit 802 is configured to generate a loop interrupt signal based on a reference sampling trigger signal according to a preset interrupt signal generating strategy.

[0101] The acquisition unit 803 is configured to trigger loop interruption according to the loop interruption signal, and acquire three-phase inductor current values ​​of the three-phase inverter circuit during the loop interruption process to obtain the three-phase inductor current values.

[0102] As an embodiment, the device for obtaining the inductor current of the three-phase inverter circuit further includes:

[0103] The sampling unit is used to sample the inductor current through the Hall sensor in the ADC sampling circuit according to the reference sampling trigger signal to obtain current sample data; wherein the sampling time of the current sample data corresponds to the triggering time of the reference sampling trigger signal.

[0104] The calculation unit is used to calculate the inductor current value using the current sample data.

[0105] As an embodiment, the device for obtaining the inductor current of the energy storage converter further includes:

[0106] The driving signal acquiring unit is used to acquire the driving signal output by the driving unit to the three-phase bridge arm circuit in response to a preset voltage regulation instruction.

[0107] The execution unit is configured to re-execute the step of generating a reference sampling trigger signal in response to a preset operation of sampling the inductor current based on the driving signal.

[0108] It is understandable that the improvements and specific implementations related to this application have been Figures 1 to 7 The corresponding embodiments are described in detail. Figures 1 to 7 On the basis of the corresponding embodiment, let Figure 8 The embodiment provides a unit in the apparatus for obtaining the inductor current of a three-phase inverter circuit to execute each step in the above method embodiment, so it will not be described in detail here.

[0109] Figure 9 This is a structural block diagram of an electronic device provided in an embodiment of the present application. Figure 9 As shown, the electronic device 9 of this embodiment includes: a processor 90, a memory 91, and a computer program 92 stored in the memory 91 and executable on the processor 90, such as a program for a method for obtaining the inductor current of a three-phase inverter circuit. When the processor 90 executes the computer program 92, the steps of each embodiment of the method for obtaining the inductor current of a three-phase inverter circuit are implemented, such as Figures 1 to 5 Alternatively, the processor 90 executes the computer program 92 to implement the above Figure 8 The functions of each unit in the corresponding embodiment. Figure 8 The relevant descriptions in the corresponding embodiments are not repeated here.

[0110] Exemplarily, the computer program 92 may be divided into one or more units, which are stored in the memory 91 and executed by the processor 90 to implement the present application. The one or more units may be a series of computer program instruction segments capable of performing specific functions, which are used to describe the execution process of the computer program 92 in the electronic device 9. For example, the computer program 92 may be divided into a trigger signal generating unit, an interrupt signal generating unit, and an acquisition unit, and the specific functions of each unit are as described above.

[0111] The electronic device may include, but is not limited to, a processor 90 and a memory 91. Those skilled in the art will understand that Figure 9 It is only an example of the electronic device 9 and does not constitute a limitation of the electronic device 9. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the electronic device may also include input and output devices (such as inverters, energy storage converters, etc.), network access equipment, buses, etc.

[0112] The processor 90 may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0113] The memory 91 can be an internal storage unit of the electronic device 9, such as a hard disk or memory of the electronic device 9. The memory 91 can also be an external storage device of the electronic device 9, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the electronic device 9. Furthermore, the memory 91 can also include both an internal storage unit of the electronic device 9 and an external storage device. The memory 91 is used to store the computer program and other programs and data required by the electronic device. The memory 91 can also be used to temporarily store data that has been output or is about to be output.

[0114] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the scope of protection of the present application.

Claims

1. A method for obtaining the inductor current of a three-phase inverter circuit, characterized in that: include: In response to a preset operation of sampling the inductor current, a reference sampling trigger signal is generated; wherein the reference sampling trigger signal is used to indicate a sampling timing of the three-phase inductor current of the three-phase inverter circuit; Generate a loop interrupt signal based on the reference sampling trigger signal according to a preset interrupt signal generation strategy; A loop interruption is triggered according to the loop interruption signal, and three-phase inductor current values ​​of the three-phase inverter circuit are obtained during the loop interruption process.

2. The method for obtaining the inductor current of a three-phase inverter circuit according to claim 1, wherein: The generating of the reference sampling trigger signal comprises: Obtaining a triangular carrier signal of the three-phase inverter circuit; The reference sampling trigger signal is generated according to the triangular carrier signal; wherein the flipping moment of the triangular carrier signal corresponds to the triggering moment of the reference sampling trigger signal.

3. The method for obtaining the inductor current of a three-phase inverter circuit according to claim 1, wherein: The three-phase inverter circuit includes a three-phase bridge arm circuit; The generating of the reference sampling trigger signal comprises: Obtaining a PWM signal corresponding to a first bridge arm in the three-phase bridge arm circuit; wherein the first bridge arm is any bridge arm in the three-phase bridge arm circuit; determining a first midpoint moment of a first state level and a second midpoint moment of a second state level in the PWM signal; The reference sampling trigger signal is generated according to the first midpoint time and the second midpoint time; wherein the triggering time of the reference sampling trigger signal corresponds to the first midpoint time and the second midpoint time.

4. The method for obtaining the inductor current of a three-phase inverter circuit according to claim 1, wherein: The three-phase inverter circuit includes a three-phase bridge arm circuit and a driving unit for driving the three-phase bridge arm circuit. After the steps of triggering a loop interruption according to the loop interruption signal and obtaining three-phase inductor current values ​​of the three-phase inverter circuit during the loop interruption process, the three-phase inverter circuit further includes: In response to a preset voltage regulation instruction, obtaining a driving signal output by the driving unit to the three-phase bridge arm circuit; Based on the driving signal, the step of generating a reference sampling trigger signal in response to the preset operation of sampling the inductor current is re-executed.

5. The method for obtaining the inductor current of a three-phase inverter circuit according to claim 4, wherein: The driving signal includes a PWM signal corresponding to a first bridge arm in the three-phase bridge arm circuit; wherein the first bridge arm is any bridge arm in the three-phase bridge arm circuit.

6. The method for obtaining the inductor current of a three-phase inverter circuit according to claim 1, wherein: The preset interrupt signal generation strategy includes a minimum redundancy time; Generating a loop interrupt signal based on the reference sampling trigger signal according to a preset interrupt signal generation strategy includes: Determining a pulse width end point of the reference sampling trigger signal; A loop interruption signal is generated according to the pulse width end point and the minimum redundancy time; wherein the pulse width start point of the loop interruption signal and the pulse width end point of the reference sampling trigger signal are separated by at least the minimum redundancy time.

7. The method for obtaining the inductor current of a three-phase inverter circuit according to any one of claims 1 to 6, characterized in that: The three-phase inverter circuit includes a three-phase bridge arm circuit and an ADC sampling circuit connected to the three-phase bridge arm circuit, wherein the ADC sampling circuit includes a Hall sensor; After the step of generating a reference sampling trigger signal in response to the preset operation of sampling the inductor current, the method further includes: According to the reference sampling trigger signal, the inductor current of the three-phase bridge arm circuit is sampled by the Hall sensor in the ADC sampling circuit to obtain three sets of current sample data; wherein the sampling time of the three sets of current sample data corresponds to the triggering time of the reference sampling trigger signal; The three-phase inductor current values ​​are obtained by calculation using the three sets of current sample data.

8. The method for obtaining the inductor current of a three-phase inverter circuit according to claim 7, wherein: The calculating and obtaining the three-phase inductor current values ​​by using the three sets of current sample data includes: The three groups of current sample data are respectively averaged to obtain the three-phase inductor current values.

9. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the electronic device, wherein when the processor executes the computer program, the steps of the method for obtaining the inductor current of a three-phase inverter circuit as claimed in any one of claims 1 to 8 are implemented.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method for obtaining the inductor current of a three-phase inverter circuit according to any one of claims 1 to 8 are implemented.

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