Inverter circuit control method, device and inverter module

Abstract

The application provides an inverter circuit control method and device and an inverter module, and relates to the technical field of power electronics. The inverter circuit control method comprises the following steps: acquiring a detected AC parameter of an inverter circuit and a detected DC parameter of the inverter circuit; determining a switching control parameter of the inverter circuit according to the detected AC parameter, a corresponding given AC parameter, the detected DC parameter and a corresponding given DC parameter; and determining a switching control signal according to the switching control parameter, the switching control signal being used for controlling a switching unit of the inverter circuit. According to the given DC parameter of the DC side, the given AC parameter of the AC side and the detected AC parameter and the detected DC parameter, the switching control parameter of the inverter circuit is determined, then the switching control signal is determined according to the switching control parameter, the control of the inverter circuit is realized, the mutual constraint between the DC side and the AC side is realized, and the comprehensive optimization control is more favorable.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power electronics, in particular to an inverter circuit control method and device and an inverter module. BACKGROUND

[0002] Traditional grid-connected inverter circuits such as photovoltaic inverter circuits track and regulate output power by adjusting DC voltage MPPT, which is a composite control strategy. If a battery is connected to the DC side, there is no need for MPPT adjustment. In the general mode, there are two modes: inverter mode (battery discharge) and charging mode, which are self-contained systems, loop decoupled, and require switching control systems, and cannot be freely bidirectional switched and multi-objective optimized.

[0003] However, grid-connected inverter circuits commonly use AC control strategies, such as active and reactive power adjustment based on the rotating coordinate system. During charging, the DC voltage and current compete, and the DC control and AC control are decoupled, which is not conducive to comprehensive optimization control and cannot be freely bidirectional switched. For example, during inverter discharge, the DC side does not participate in control, and once the battery voltage is under-voltage, the system must be protected and shut down. The AC control has the risk of over-voltage of the battery voltage during charging.

[0004] Therefore, a method is needed to combine DC control and AC control for comprehensive optimization control. SUMMARY

[0005] The present application relates to the technical field of power electronics, in particular to an inverter circuit control method and device and an inverter module.

[0006] To achieve the above object, the technical solutions adopted by the embodiments of the present application are as follows:

[0007] In a first aspect, the embodiments of the present application provide an inverter circuit control method, comprising:

[0008] obtaining detected AC electrical parameters of an inverter circuit and detected DC electrical parameters of the inverter circuit;

[0009] determining switching control parameters of the inverter circuit according to the detected AC electrical parameters and corresponding given AC electrical parameters, the detected DC electrical parameters and corresponding given DC electrical parameters;

[0010] determining a switching control signal according to the switching control parameters, the switching control signal being used to control a switching unit of the inverter circuit.

[0011] In an optional implementation, the determining the switching control parameter of the inverter circuit according to the detected AC parameter and the corresponding given AC parameter, the detected DC parameter and the corresponding given DC parameter comprises:

[0012] determining the AC control parameter of the inverter circuit according to the detected AC parameter and the corresponding given AC parameter;

[0013] determining the DC control parameter of the inverter circuit according to the detected DC parameter and the corresponding given DC parameter;

[0014] determining the switching control parameter of the inverter circuit according to one of the AC control parameter and the DC control parameter.

[0015] In an optional implementation, the detected DC parameter comprises a detected DC voltage value and a detected DC current value, and the given DC parameter comprises a given DC voltage value and a given DC current value.

[0016] The determining the DC control parameter of the inverter circuit according to the detected DC parameter and the corresponding given DC parameter comprises:

[0017] determining a first control parameter of the inverter circuit according to the detected DC voltage value and the given DC voltage value;

[0018] determining a second control parameter of the inverter circuit according to the detected DC current value and the given DC current value;

[0019] performing a maximum operation on the first control parameter and the second control parameter to determine a target DC control parameter;

[0020] The determining the switching control parameter of the inverter circuit according to one of the AC control parameter and the DC control parameter comprises:

[0021] determining the switching control parameter of the inverter circuit according to one of the target DC control parameter and the AC control parameter.

[0022] In an optional implementation, the given DC parameter further comprises a maximum DC voltage value.

[0023] The determining the DC control parameter of the inverter circuit according to the detected DC parameter and the corresponding given DC parameter comprises:

[0024] determining a third control parameter of the inverter circuit according to the detected DC voltage value and the maximum DC voltage value;

[0025] The determining the switching control parameter of the inverter circuit according to one of the target DC control parameter and the AC control parameter comprises:

[0026] The switching control parameter of the inverter circuit is obtained according to one of the third control parameter, the AC control parameter and the target DC control parameter.

[0027] In an optional implementation, the obtaining the switching control parameter of the inverter circuit according to one of the third control parameter, the AC control parameter and the target DC control parameter comprises:

[0028] The fourth control parameter of the inverter circuit is determined by performing a maximum operation on the third control parameter and the AC control parameter.

[0029] The switching control parameter of the inverter circuit is obtained according to one of the fourth control parameter and the target DC control parameter.

[0030] In an optional implementation, the detecting the AC parameter comprises detecting a reactive current value and detecting an active current value, and the given AC parameter comprises a given reactive current value and a given active current value.

[0031] The determining the switching control parameter of the inverter circuit according to one of the detected AC parameter and the corresponding given AC parameter, the detected DC parameter and the corresponding given DC parameter comprises:

[0032] The active AC control parameter is generated according to the detected active current value and the given active current value.

[0033] The reactive AC control parameter is generated according to the detected reactive current value and the given reactive current value.

[0034] The active switching control parameter of the inverter circuit is determined according to one of the active AC control parameter and the DC control parameter, and the switching control parameter of the inverter circuit comprises the active switching control parameter and the reactive AC control parameter.

[0035] In an optional implementation, the obtaining the switching control parameter of the inverter circuit according to one of the fourth control parameter and the target DC control parameter comprises:

[0036] The switching control parameter of the inverter circuit is obtained by performing a minimum operation on the fourth control parameter and the target DC control parameter.

[0037] In an optional implementation, if the inverter circuit is in a DC charging mode, the method further comprises:

[0038] The given DC voltage value is set to be greater than the detected DC voltage value.

[0039] The DC charging limit current value is set to be the given DC current value.

[0040] If the inverter circuit is in the AC four-quadrant operation mode, the method further comprises:

[0041] The given DC voltage value is set to be less than the detected DC voltage value.

[0042] The DC charging limit current value is set to be the given DC current value.

[0043] In an optional embodiment, if the inverter circuit is in the DC charging mode, the method further comprises:

[0044] The given reactive current value and the given active current value are set to be greater than or equal to zero.

[0045] If the inverter circuit is in the AC four-quadrant operation mode, the method further comprises:

[0046] The given reactive current value and the given active current value are set to be values within a preset range.

[0047] In a second aspect, the embodiments of the present application further provide an inverter circuit control device, comprising:

[0048] An acquisition module is configured to acquire detected AC electrical parameters of an inverter circuit and detected DC electrical parameters of the inverter circuit.

[0049] A determination module is configured to determine switching control parameters of the inverter circuit according to the detected AC electrical parameters and corresponding given AC electrical parameters, the detected DC electrical parameters and corresponding given DC electrical parameters.

[0050] A control module is configured to determine a switching control signal according to the switching control parameters, the switching control signal being used to control a switching unit of the inverter circuit.

[0051] In a third aspect, the embodiments of the present application further provide an inverter module, comprising: an inverter circuit and a control unit, a switching unit in the inverter circuit being connected to the control unit, and the control unit being configured to perform steps of the inverter circuit control method according to any one of the first aspect.

[0052] The present application has the following beneficial effects:

[0053] The application provides an inverter circuit control method and device and an inverter module. BRIEF DESCRIPTION OF DRAWINGS

[0054] In order to more clearly illustrate the technical solutions of the embodiments of the application, the drawings needed to be used in the embodiments will be briefly introduced as follows. It should be understood that the following drawings only show some of the embodiments of the application, and therefore should not be regarded as a limitation to the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0055] Figure 1 An inverter module is provided for the embodiments of the application.

[0056] Figure 2 One of the flowcharts of the inverter circuit control method provided for the embodiments of the application is shown in FIG. 1.

[0057] Figure 3 One of the schematic diagrams of the inverter circuit control method provided for the embodiments of the application is shown in FIG. 2.

[0058] Figure 4 The second flowchart of the inverter circuit control method provided for the embodiments of the application is shown in FIG. 3.

[0059] Figure 5 The third flowchart of the inverter circuit control method provided for the embodiments of the application is shown in FIG. 4.

[0060] Figure 6 The fourth flowchart of the inverter circuit control method provided for the embodiments of the application is shown in FIG. 5.

[0061] Figure 7 The fifth flowchart of the inverter circuit control method provided for the embodiments of the application is shown in FIG. 6.

[0062] Figure 8A sixth flowchart of a control method of an inverter circuit according to an embodiment of the present application is provided;

[0063] Figure 9 A schematic diagram of acquiring detection of an AC parameter according to an embodiment of the present application is provided;

[0064] Figure 10 A second schematic diagram of a control method of an inverter circuit according to an embodiment of the present application is provided;

[0065] Figure 11 A functional module schematic diagram of a control device of an inverter circuit according to an embodiment of the present application is provided. DETAILED DESCRIPTION

[0066] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application.

[0067] Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art without creative labor based on the embodiments in the present application are within the scope of protection of the present application.

[0068] In the description of the present application, it should be noted that if the terms "upper", "lower", etc. indicate the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly used when the product of the present application is used, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as limiting the device or element indicated to have a specific orientation, to be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application.

[0069] In addition, the terms "first", "second", etc. in the specification and claims of the present application and the above drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device that includes a series of steps or units does not have to be limited to only those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to the process, method, product or device.

[0070] It should be noted that the features in the embodiments of the present application can be combined with each other without conflict.

[0071] In order to realize the mutual constraint of the direct current side and the alternating current side of the inverter circuit and realize normal operation in multiple modes, the embodiments of the present application provide an inverter circuit control method, so as to realize normal operation in different modes according to the detection value of the inverter circuit and the given reference value. Before describing the inverter circuit control method, the embodiments of the present application can first explain and describe the inverter circuit control system, Figure 1 An inverter module provided by the embodiments of the present application is shown in the figure. Figure 1 As shown in the figure, the inverter module includes an inverter circuit and a control unit, wherein the inverter circuit can include a direct current power supply, a capacitor, a switching unit, an inductor, a filter and the like, and the direct current side can include the capacitor and the direct current power supply. The control device is connected to the switching unit in the inverter circuit and is used to control the inverter circuit, wherein the switching unit can be composed of six switching tubes. For example, if the direct current power supply is Vdc, the capacitor Cdc is connected in parallel with the direct current power supply, the inductors are L1, L2 and L3 respectively, and the six switching tubes of the switching unit are Q1, Q2, Q3, Q4, Q5 and Q6 respectively, wherein Q1 and Q2 can be connected to the inductor L1 and controlled, Q3 and Q4 can be connected to the inductor L2 and controlled, and Q5 and Q6 can be connected to the inductor L3 and controlled. The inductor currents are ILA, ILB and ILC respectively, and the alternating current side currents, i.e. the grid side currents, are IA, IB and IC respectively after the filter. At this time, the voltages are Ua, Ub and Uc respectively.

[0072] The control in each mode is realized according to the voltages Ua, Ub and Uc, the alternating current side currents and the given parameters. The inverter circuit control method provided by the present application is explained and described in detail by multiple embodiments in combination with the accompanying drawings.

[0073] In order to enable the control device to execute the inverter circuit control method, a detection program can be pre-integrated and installed in the control device, and the control device can be realized by running an algorithm or software. The control device can be a server or a terminal, Figure 2 A flowchart of the inverter circuit control method provided by the embodiments of the present application is shown in the figure. Figure 3 A schematic diagram of the inverter circuit control method provided by the embodiments of the present application is shown in the figure. Figure 3 The inverter circuit control method is further described as shown in the figure. Figure 2 The method includes the following steps.

[0074] In S101, detection alternating current parameters of the inverter circuit and detection direct current parameters of the inverter circuit are obtained.

[0075] In the embodiments of the present application, the detected AC parameter of the inverter circuit refers to the AC parameter detected on the AC side of the inverter circuit, and the detected DC parameter of the inverter circuit refers to the DC parameter detected on the DC side of the inverter circuit.

[0076] S102, according to the detected AC parameter and the corresponding given AC parameter, the detected DC parameter and the corresponding given DC parameter, the switching control parameter of the inverter circuit is determined.

[0077] The given AC parameter corresponds to the detected AC parameter, and is used to make the value of the final output close to the given AC parameter. Similarly, the given DC parameter corresponds to the detected DC parameter, and is used to make the value of the final output close to the given DC parameter.

[0078] The switching control parameter of the inverter circuit is determined by comparing the detected AC parameter with the given AC parameter, and comparing the detected DC parameter with the given DC parameter.

[0079] S103, according to the switching control parameter, the switching control signal is determined, and the switching control signal is used to control the switching unit of the inverter circuit.

[0080] The switching control parameter is input into the rotating inverse transformation, i.e., dq / abc transformation, so as to generate the given current value of the inverter circuit. The obtained given current value is input into the inductance current instantaneous inner loop, and the output result is passed through the pulse width modulation (PWM) circuit, so as to obtain the PWM signal of the upper and lower switching units connected with the inductor phase, i.e., the switching control signal. According to the switching control signal, the switching unit of the inverter circuit can be controlled respectively.

[0081] As shown in the example, Figure 3 If the inverter circuit includes a three-phase inductor, a three-phase voltage is output, the switching control parameter is input into the rotating inverse transformation, i.e., dq / abc transformation, so as to generate the three-phase given current value of the inverter circuit. The obtained three-phase given current value is input into the three-phase inductance current instantaneous inner loop, and the output result is passed through the pulse width modulation circuit, so as to obtain the switching control signal of the upper and lower switching units connected with the inductor phase.

[0082] The switching unit in the inverter circuit can be a plurality of switching tube networks, and the switching unit of the inverter circuit is controlled according to the switching control signal, so that the switching unit in the inverter circuit is turned on and closed, thereby affecting the inductance current and the three-phase voltage, and enabling the inverter circuit to work in the preset working mode.

[0083] To sum up, the application provides an inverter circuit control method, comprising: obtaining detection AC parameters of the inverter circuit and detection DC parameters of the inverter circuit; determining switching control parameters of the inverter circuit according to the detection AC parameters, corresponding given AC parameters, the detection DC parameters and corresponding given DC parameters; and determining switching control signals according to the switching control parameters, the switching control signals being used for controlling switching units of the inverter circuit. According to the method, the switching control parameters of the inverter circuit are determined according to the multiple targets, i.e., the given DC parameters, the multiple targets, i.e., the given AC parameters, the detection AC parameters and the detection DC parameters, and then the given current value and the switching control signals are determined according to the switching control parameters to control the inverter circuit, so that the DC side and the AC side are mutually constrained, and the comprehensive optimization control is more favorable.

[0084] On the basis of the inverter circuit control method provided in the above embodiment, the application further provides another possible implementation example of the inverter circuit control method. Figure 4 A flowchart of another inverter circuit control method provided in the application is shown in FIG. 2. As shown in FIG. 2, the switching control parameters of the inverter circuit are determined according to the detection AC parameters, corresponding given AC parameters, detection DC parameters and corresponding given DC parameters, comprising: Figure 4

[0085] S201, determining AC control parameters of the inverter circuit according to the detection AC parameters and corresponding given AC parameters.

[0086] In the embodiment, the given AC parameters correspond to the detection AC parameters, and are used for making the final output value close to the given AC current value. The detection AC parameters and the given AC parameters are input into the AC current loop, and the AC control parameters are calculated by subtracting the detection AC current value from the given AC current value.

[0087] S202, determining DC control parameters of the inverter circuit according to the detection DC parameters and corresponding given DC parameters.

[0088] ​Specifically, similar to the step S201, the given DC parameter and the detected DC parameter correspond to each other, and are used to make the final output value close to the given DC current or voltage value. The detected DC parameter and the given DC parameter are input into the DC current loop or the DC voltage loop, and the given DC parameter and the detected DC parameter are processed by a linear controller (PI) of the DC current loop or the DC voltage loop. The specific processing manner is to subtract the given DC parameter from the detected DC parameter, and then multiply the obtained result by -1, so that the DC positive direction is consistent with the reference direction, thereby calculating the DC control parameter.

[0089] S203, determining the switching control parameter of the inverter circuit according to one of the AC control parameter and the DC control parameter.

[0090] According to one of the AC control parameter and the DC control parameter calculated in the steps S201 and S202, and in combination with the preset reference phase, the switching control parameter of the inverter circuit is determined.

[0091] In the method provided in the embodiment, the AC control parameter of the inverter circuit is determined according to the detected AC parameter and the corresponding given AC parameter, the DC control parameter of the inverter circuit is determined according to the detected DC parameter and the corresponding given DC parameter, and finally the switching control parameter of the inverter circuit is determined according to one of the AC control parameter and the DC control parameter. The switching control parameter of the inverter circuit is determined through the detection data on the DC side and the detection data on the AC side, which is more conducive to comprehensive optimization control and realization of mutual constraint and free bidirectional switching between the DC side and the AC side.

[0092] As shown in the above embodiment, the detected DC parameter includes a detected DC voltage value and a detected DC current value, and the given DC parameter includes a given DC voltage value and a given DC current value. Therefore, the embodiment of the application further provides a possible implementation manner of obtaining the detected AC parameter of the inverter circuit, Figure 5 A flowchart of a third embodiment of the inverter circuit control method provided in the application is shown in FIG. 3. Figure 5 As shown in FIG. 3, the DC control parameter of the inverter circuit is determined according to the detected DC parameter and the corresponding given DC parameter, including:

[0093] S301, determining the first control parameter of the inverter circuit according to the detected DC voltage value and the given DC voltage value.

[0094] In the embodiment, the given DC voltage value and the detected DC voltage value are input into the DC voltage loop, and the given DC voltage value and the detected DC voltage value are processed by the linear controller in the DC voltage loop. For example, the given DC voltage value can be represented as Vdc*, and the detected DC voltage value can be represented as Vdc. Since the DC positive direction is opposite to the reference direction, the linear controller is obtained by subtracting the given DC voltage value from the detected DC voltage value, and then multiplying the result by -1, so that the DC positive direction is consistent with the reference direction, thereby determining the first control parameter of the inverter circuit.

[0095] S302, according to the detected DC current value and the given DC current value, determining the second control parameter of the inverter circuit.

[0096] Specifically, similar to the method provided in step S301, the given DC current value and the detected DC current value are input into the DC current loop, and the given DC current value and the detected DC current value are processed by the linear controller in the DC current loop. The specific processing method is to subtract the given DC current value from the detected DC current value, and then multiply the result by -1, so that the DC positive direction is consistent with the reference direction, thereby determining the second control parameter of the inverter circuit.

[0097] S303, performing a maximum operation on the first control parameter and the second control parameter to determine a target DC control parameter.

[0098] According to the first control parameter and the second control parameter obtained in steps S301 and S302 respectively, and performing a maximum operation on the first control parameter and the second control parameter, in fact, the output of the DC voltage loop and the DC current loop competes, and the maximum value of the first control parameter and the second control parameter is selected as the target DC control parameter.

[0099] The above method of determining the switching control parameter of the inverter circuit according to one of the AC control parameter and the DC control parameter comprises:

[0100] S304, determining the switching control parameter of the inverter circuit according to one of the target DC control parameter and the AC control parameter.

[0101] According to the target DC control parameter and one of the AC control parameters obtained in steps S303 and S201, the switching control parameter of the inverter circuit is determined.

[0102] In the method provided in the embodiment, the first control parameter of the inverter circuit is determined according to the detected DC voltage value and the given DC voltage value, the second control parameter of the inverter circuit is determined according to the detected DC current value and the given DC current value, the target DC control parameter is determined by performing the maximum operation on the first control parameter and the second control parameter, and finally the switching control parameter of the inverter circuit is determined according to one of the target DC control parameter and the AC control parameter. The switching control parameter of the inverter circuit is determined through the first control parameter and the second control parameter on the DC side and the AC control parameter on the AC side, so that the comprehensive optimization control is more conducive to the mutual constraint and the free bidirectional switching of the DC side and the AC side.

[0103] On the basis of the inverter circuit control method provided in the above embodiment, the embodiment of the application further provides another possible implementation example of the inverter circuit control method. Figure 6 FIG. 4 is a flowchart of an inverter circuit control method provided in the embodiment of the application; the given DC parameters further include a maximum DC voltage value; as shown in the figure, the DC control parameter of the inverter circuit is determined according to the detected DC parameters and the corresponding given DC parameters, including: Figure 6

[0104] S401, the third control parameter of the inverter circuit is determined according to the detected DC voltage value and the maximum DC voltage value.

[0105] In the embodiment, the maximum DC voltage value and the detected DC voltage value are input into the maximum DC voltage loop, and the maximum DC voltage value and the detected DC voltage value are processed by the linear controller in the maximum DC voltage loop; for example, the maximum DC voltage value can be represented as Vdc_max*, and the detected DC voltage value can be represented as Vdc. Since the DC positive direction is opposite to the reference direction, the linear controller subtracts the maximum DC voltage value from the detected DC voltage value, and then multiplies the calculated result by -1, so that the DC positive direction is consistent with the reference direction, thereby determining the third control parameter of the inverter circuit.

[0106] The switching control parameter of the inverter circuit is determined according to one of the target DC control parameter and the AC control parameter, including:

[0107] S402, the switching control parameter of the inverter circuit is obtained according to one of the third control parameter, the AC control parameter and the target DC control parameter.

[0108] The switching control parameter of the inverter circuit is determined according to one of the third control parameter, the target DC control parameter and the AC control parameter calculated in the above step S401, step 303 and step S201.

[0109] ​In the method provided in the embodiment, the third control parameter of the inverter circuit is determined according to the detected direct current voltage value and the maximum direct current voltage value, and the switching control parameter of the inverter circuit is obtained according to one of the third control parameter, the alternating current control parameter and the target direct current control parameter. The switching control parameter of the inverter circuit is determined through the third control parameter on the direct current side, the target direct current control parameter and the alternating current control parameter on the alternating current side, so that the comprehensive optimization control is more conducive to the mutual constraint and the free bidirectional switching of the direct current side and the alternating current side.

[0110] On the basis of the inverter circuit control method provided in the above embodiment, the embodiment of the application further provides another possible implementation example of the inverter circuit control method. Figure 7 As shown in FIG. 5, the switching control parameter of the inverter circuit is obtained according to one of the third control parameter, the alternating current control parameter and the target direct current control parameter, including: Figure 7

[0111] S501, performing a maximum operation on the third control parameter and the alternating current control parameter to determine a fourth control parameter of the inverter circuit.

[0112] In the embodiment of the application, the maximum operation on the third control parameter and the alternating current control parameter is actually the output competition of the alternating current loop and the maximum direct current voltage loop, and the maximum value of the third control parameter and the alternating current control parameter is selected as the fourth control parameter of the inverter circuit.

[0113] S502, obtaining the switching control parameter of the inverter circuit according to one of the fourth control parameter and the target direct current control parameter.

[0114] Optionally, the switching control parameter of the inverter circuit is obtained by performing a minimum operation on the fourth control parameter and the target direct current control parameter.

[0115] Specifically, the fourth control parameter and the target direct current control parameter are calculated according to the above step S501 and step S303, and the minimum value of the fourth control parameter and the target direct current control parameter is selected as the switching control parameter of the inverter circuit.

[0116] In the method provided in the embodiment, the fourth control parameter of the inverter circuit is determined by performing a maximum operation on the third control parameter and the alternating current control parameter, and the switching control parameter of the inverter circuit is obtained according to one of the fourth control parameter and the target direct current control parameter. The fourth control parameter is determined through the third control parameter on the direct current side and the alternating current control parameter on the alternating current side, and the switching control parameter of the inverter circuit is determined together with the target direct current control parameter, which is conducive to the comprehensive optimization control and the mutual constraint and the free bidirectional switching of the direct current side and the alternating current side.

[0117] ​The detecting the AC parameter as shown in the above embodiment includes detecting a reactive current value and detecting an active current value, and the given AC parameter includes a given reactive current value and a given active current value. Therefore, the embodiment of the present application further provides a possible implementation of the inverter circuit control method, Figure 8 A flowchart of a sixth inverter circuit control method provided by the embodiment of the present application is shown in FIG. 6. Figure 9 A schematic diagram of obtaining the detecting AC parameter provided by the embodiment of the present application is shown in FIG. 5. Figure 8 As shown, the switching control parameter of the inverter circuit is determined according to the detecting AC parameter, the corresponding given AC parameter, the detecting DC parameter and the corresponding given DC parameter, and includes:

[0118] S601, generating an active AC control parameter according to the detecting active current value and the given active current value.

[0119] In the embodiment, the given active current value corresponds to the detecting active current value, and is used to make the final output value close to the given active current value. The given active current value and the detecting active current value are input into the active current loop, and the initial given active voltage reference value is calculated by subtracting the detecting active current value from the given active current value. For example, the given active current value can be represented as Iq*, and the detecting active current value can be represented as Iq. The active current loop processes the given active current value and the detecting active current value in the following manner. Since the active current loop has a linear controller, a control deviation can be formed according to the given active current value and the actual detecting active current value, and a control quantity is formed by linearly combining the proportion and integral of the deviation, and the active AC control parameter is obtained.

[0120] S602, generating a reactive AC control parameter according to the detecting reactive current value and the given reactive current value.

[0121] Specifically, the given reactive current value corresponds to the detecting reactive current value, and is used to make the final output value close to the given reactive current value. The given reactive current value and the detecting reactive current value are input into the reactive current loop, and the given reactive voltage reference value is calculated by subtracting the detecting reactive current value from the given reactive current value. For example, the given reactive current value can be represented as Id*, and the detecting reactive current value can be represented as Id. The reactive current loop processes the given reactive current value and the detecting reactive current value in the following manner. Since the reactive current loop has a linear controller, a control deviation can be formed according to the given reactive current value and the actual detecting reactive current value, and a control quantity is formed by linearly combining the proportion and integral of the deviation, and the reactive AC control parameter is obtained.

[0122] S603, determining an active switching control parameter of the inverter circuit according to one of the active AC control parameter and the DC control parameter.

[0123] The switching control parameters of the inverter circuit include active switching control parameters and reactive AC control parameters. The active AC control parameters and one of the DC control parameters obtained according to the steps S601 and S202 are used to determine the active switching control parameters of the inverter circuit.

[0124] It should be noted that, as an example, the active current value and the reference phase are calculated according to the voltage on the AC side of the inverter circuit.

[0125] In this embodiment, the AC side of the inverter circuit is combined with Figure 9 The process of obtaining the detected AC parameters is described in detail as follows. Figure 9 As shown in the figure, the detected three-phase voltage Ua, Ub and Uc on the AC side of the inverter circuit are input into a phase-locked loop (PLL) to obtain the reference phase and the reference voltage phase represented by θ, and other parameters such as the frequency represented by ω and the amplitude information, etc. Then, the detected three-phase current Ia, Ib, Ic on the AC side of the inverter circuit and the reference voltage phase θ are input into a current detection algorithm to decompose the three-phase current on the AC side of the inverter circuit to obtain the detected reactive current value represented by Id and the detected active current value represented by Iq.

[0126] The amplitude of each of the output of the reactive current loop, the active current loop, the maximum DC voltage loop, the DC voltage loop and the DC current loop in the above embodiment is limited so that the value output by each loop can support the normal operation of the inverter circuit in multiple modes.

[0127] In the method provided in this embodiment, the active AC control parameters are generated according to the detected active current value and the given active current value, the reactive AC control parameters are generated according to the detected reactive current value and the given reactive current value, and the active switching control parameters of the inverter circuit are determined according to one of the active AC control parameters and the DC control parameters. The switching control parameters of the inverter circuit are determined according to the DC control parameters on the DC side and the active AC control parameters on the AC side, which is conducive to comprehensive optimization control and realization of mutual constraint and free bidirectional switching between the DC side and the AC side.

[0128] The present application also provides a complete possible implementation of the inverter circuit control method, Figure 10 Fig. 2 is a schematic diagram of an inverter circuit control method provided in an embodiment of the present application. As shown in the figure, Figure 10As shown, the detection AC parameter of the AC side of the inverter circuit includes: detection reactive current value Id and detection active current value Iq, the given AC parameter includes: given reactive current value Id* and given active current value Iq*, the detection active current value Iq and the given active current value Iq* are input into the active current loop to generate the active AC control parameter, and the detection reactive current value Id and the given reactive current value Id* are input into the reactive current loop to generate the reactive AC control parameter.

[0129] The detection DC parameter of the DC side of the inverter circuit includes: detection DC voltage value Vdc and detection DC current value Idc, the given DC parameter includes: given DC voltage value Vdc*, given DC current value Idc* and maximum DC voltage value Vdc_max*, the given DC voltage value Vdc* and the detection DC voltage value Vdc are input into the DC voltage loop to determine the first control parameter of the inverter circuit, the detection DC current value Idc and the given DC current value Idc* are input into the DC current loop to determine the second control parameter of the inverter circuit, and the maximum DC voltage value Vdc_max* and the detection DC voltage value Vdc are input into the maximum DC voltage loop to determine the third control parameter of the inverter circuit.

[0130] The maximum operation is performed according to the first control parameter and the second control parameter to determine the target DC control parameter, the maximum operation is performed according to the third control parameter and the active AC control parameter to determine the fourth control parameter of the inverter circuit, and finally the minimum operation is performed according to the fourth control parameter and the target DC control parameter to obtain the switching control parameter of the inverter circuit, wherein the switching control parameter of the inverter circuit further includes the reactive AC control parameter and a preset phase.

[0131] The inverter circuit has different settings for each target parameter in different working modes, and therefore the application further provides possible implementation examples of controlling the inverter circuit in the DC charging mode and the AC four-quadrant charging mode.

[0132] (1) If the inverter circuit is in the DC charging mode, the method further includes: setting the given DC voltage value to be greater than the detection DC voltage value. The DC charging mode example can be a mode of charging the power grid with the energy storage battery, which is similar to the mode of charging the device with the charging pile. In the DC charging mode, the given DC voltage value is set to be greater than the detection DC voltage value.

[0133] The DC charging limit current value is set to be the given DC current value. The DC charging limit current value is set to be the given DC current value, and then the device or the power grid is charged through the set DC charging limit current value.

[0134] Optionally, in the direct current charging mode, a given reactive current value and a given active current value are set, such that the given reactive current value and the given active current value are both greater than or equal to zero.

[0135] It should be noted that, when the inverter circuit is in the direct current charging mode, the maximum direct current voltage value is the charging maximum operating voltage value, so that the inverter circuit normally works in the direct current charging mode.

[0136] (2) If the inverter circuit is in the alternating current four-quadrant working mode, the method further comprises: setting a given direct current voltage value, such that the given direct current voltage value is less than the detected direct current voltage value.

[0137] The alternating current four-quadrant working mode can be a mode in which charging or discharging between the energy storage battery and the power grid is freely performed. When the inverter circuit is in the alternating current four-quadrant working mode, the given direct current voltage value is set to be less than the detected direct current voltage value, that is, the given direct current voltage value is set to be the minimum voltage value for discharging in the alternating current four-quadrant working mode, so as to guarantee the minimum voltage limit for discharging in this mode.

[0138] The direct current charging limit current value is set to be the given direct current current value. It should be noted that, when the inverter circuit is in the alternating current four-quadrant working mode, the maximum direct current voltage value is the charging maximum operating voltage value, so that the inverter circuit normally works in the alternating current four-quadrant working mode. If discharging operation is performed in the alternating current four-quadrant working mode, the voltage continuously decreases, and the discharging power is automatically limited so that the current working mode is maintained at the minimum voltage, thereby avoiding the risk of battery voltage undervoltage or overvoltage.

[0139] Optionally, a given reactive current value and a given active current value are set, such that the given reactive current value and the given active current value are values within a preset range.

[0140] In the alternating current four-quadrant working mode, the given reactive current value and the given active current value are set to be any values within a preset range, so as to realize free combination between charging, discharging and reactive power in the alternating current four-quadrant mode.

[0141] For example, if the given active current value is set to be positive, the alternating current four-quadrant working mode is a discharging mode at this time, and if the given active current value is set to be negative, the alternating current four-quadrant working mode is a charging mode at this time. Whether the positive or negative given reactive current value represents inductive reactive power or capacitive reactive power depends on the setting of the preset algorithm. If the given reactive current value is set to be positive, it is capacitive reactive current, and if the given reactive current value is set to be negative, it is inductive reactive current. Similarly, if the given reactive current value is set to be positive, it is inductive reactive current, and if the given reactive current value is set to be negative, it is capacitive reactive current. In this case, no limitation is made.

[0142] In one example, if the given active current value is positive and the given reactive current value is positive, the combination of the AC four-quadrant operation mode is the combination of discharging and capacitive reactive, or the combination of discharging and inductive reactive; in another example, if the given active current value is negative and the given active current value is positive, the combination of the AC four-quadrant operation mode is the combination of charging and capacitive reactive, or the combination of charging and inductive reactive, so as to realize the free switching of charging and discharging.

[0143] In the method provided by the embodiments of the present application, when the inverter circuit is in the DC charging mode, the given DC voltage value is greater than the detected DC voltage value, the given DC voltage value is greater than the detected DC voltage value, and the DC charging limiting current value is set as the given DC current value, so that the device or the power grid is charged by the set DC charging limiting current value, so that the inverter circuit normally works in the DC charging mode. When the inverter circuit is in the AC four-quadrant operation mode, the given DC voltage value is less than the detected DC voltage value, the given reactive current value and the given active current value are values in a preset range, and the DC charging limiting current value is set as the given DC current value, so that the inverter circuit realizes the free switching of charging and discharging in the AC four-quadrant operation mode.

[0144] The following continues to explain the inverter circuit control device and the control device provided by any of the above embodiments of the present application, and the specific implementation process and the technical effects are the same as those of the corresponding method embodiments. For brief description, the parts not mentioned in the embodiments can be referred to the corresponding contents in the method embodiments.

[0145] Figure 11 A functional module schematic diagram of an inverter circuit control device provided by the embodiments of the present application is shown in FIG. 1. Figure 11 As shown in FIG. 1, the inverter circuit control device 100 includes:

[0146] The acquisition module 110 is configured to acquire the detected AC electrical parameter of the inverter circuit and the detected DC electrical parameter of the inverter circuit.

[0147] The determination module 120 is configured to determine the switching control parameter of the inverter circuit according to the detected AC electrical parameter and the corresponding given AC electrical parameter, the detected DC electrical parameter and the corresponding given DC electrical parameter.

[0148] The control module 130 is configured to determine the switching control signal according to the switching control parameter, and the switching control signal is used to control the switching unit of the inverter circuit.

[0149] In an optional implementation, the determining module 120 is further configured to determine an AC control parameter of the inverter circuit according to the detected AC parameter and the corresponding given AC parameter; determine a DC control parameter of the inverter circuit according to the detected DC parameter and the corresponding given DC parameter; and determine a switch control parameter of the inverter circuit according to one of the AC control parameter and the DC control parameter.

[0150] In an optional implementation, the determining module 120 is further configured to determine a first control parameter of the inverter circuit according to the detected DC voltage value and the given DC voltage value; determine a second control parameter of the inverter circuit according to the detected DC current value and the given DC current value; determine a target DC control parameter by performing a maximum operation on the first control parameter and the second control parameter; and determine a switch control parameter of the inverter circuit according to one of the target DC control parameter and the AC control parameter.

[0151] In an optional implementation, the determining module 120 is further configured to determine a third control parameter of the inverter circuit according to the detected DC voltage value and the maximum DC voltage value; and determine a switch control parameter of the inverter circuit according to one of the third control parameter, the AC control parameter and the target DC control parameter.

[0152] In an optional implementation, the determining module 120 is further configured to determine a fourth control parameter of the inverter circuit by performing a maximum operation on the third control parameter and the AC control parameter; and determine a switch control parameter of the inverter circuit according to one of the fourth control parameter and the target DC control parameter.

[0153] In an optional implementation, the determining module 120 is further configured to generate an active AC control parameter according to the detected active current value and the given active current value; generate a reactive AC control parameter according to the detected reactive current value and the given reactive current value; and determine an active switch control parameter of the inverter circuit according to one of the active AC control parameter and the DC control parameter.

[0154] In an optional implementation, the determining module 120 is further configured to perform a minimum operation on the fourth control parameter and the target DC control parameter to obtain the switch control parameter of the inverter circuit.

[0155] In an optional implementation, the inverter circuit control apparatus 100 further comprises:

[0156] The setting module is configured to set the given DC voltage value, and set the DC charging limit current value as the given DC current value, if the inverter circuit is in the DC charging mode; set the given DC voltage value to be less than the detected DC voltage value, if the inverter circuit is in the AC four-quadrant operation mode; and set the DC charging limit current value as the given DC current value.

[0157] In an optional embodiment, the setting module is further configured to set the given reactive current value and the given active current value to be greater than or equal to zero if the inverter circuit is in the DC charging mode; and set the given reactive current value and the given active current value to be values within a preset range if the inverter circuit is in the AC four-quadrant operation mode.

[0158] The apparatus is configured to perform the method provided by the foregoing embodiments, and has similar implementation principles and technical effects, which will not be described here.

[0159] The above modules can be one or more integrated circuits configured to implement the above method, for example, one or more application specific integrated circuits (ASICs), or one or more microprocessors, or one or more field programmable gate arrays (FPGAs), etc. For another example, when a certain module above is implemented in the form of a processing element scheduling program code, the processing element can be a general-purpose processor, such as a central processing unit (CPU) or other processor capable of invoking program code. For another example, the modules can be integrated together to implement in the form of a system on a chip (SOC).

[0160] The above merely provides a specific implementation of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An inverter circuit control method characterized by comprising: The method comprises: obtaining detection AC parameters of an inverter circuit and detection DC parameters of the inverter circuit; determining switching control parameters of the inverter circuit according to the detection AC parameters and corresponding given AC parameters, the detection DC parameters and corresponding given DC parameters; determining a switching control signal according to the switching control parameters, the switching control signal being used for controlling a switching unit of the inverter circuit; the determining of the switching control parameters of the inverter circuit according to the detection AC parameters and corresponding given AC parameters, the detection DC parameters and corresponding given DC parameters comprises: determining AC control parameters of the inverter circuit according to the detection AC parameters and corresponding given AC parameters; determining DC control parameters of the inverter circuit according to the detection DC parameters and corresponding given DC parameters; determining the switching control parameters of the inverter circuit according to one of the AC control parameters and the DC control parameters; the detection DC parameters comprise a detection DC voltage value and a detection DC current value, and the given DC parameters comprise a given DC voltage value and a given DC current value; the determining of the DC control parameters of the inverter circuit according to the detection DC parameters and corresponding given DC parameters comprises: determining a first control parameter of the inverter circuit according to the detection DC voltage value and the given DC voltage value; determining a second control parameter of the inverter circuit according to the detection DC current value and the given DC current value; performing a maximum operation on the first control parameter and the second control parameter to determine a target DC control parameter; the determining of the switching control parameters of the inverter circuit according to one of the AC control parameters and the DC control parameters comprises: determining the switching control parameters of the inverter circuit according to one of the target DC control parameter and the AC control parameter; the given DC parameters further comprise a maximum DC voltage value; the determining of the DC control parameters of the inverter circuit according to the detection DC parameters and corresponding given DC parameters comprises: determining a third control parameter of the inverter circuit according to the detection DC voltage value and the maximum DC voltage value; the determining of the switching control parameters of the inverter circuit according to one of the target DC control parameter and the AC control parameter comprises: determining the switching control parameters of the inverter circuit according to one of the third control parameter, the AC control parameter and the target DC control parameter.

2. The method of claim 1, wherein, the determining of the switching control parameters of the inverter circuit according to one of the third control parameter, the AC control parameter and the target DC control parameter comprises: performing a maximum operation on the third control parameter and the AC control parameter to determine a fourth control parameter of the inverter circuit; determining the switching control parameters of the inverter circuit according to one of the fourth control parameter and the target DC control parameter.

3. The method according to any one of claims 1-2, characterized in that, The detection AC parameter includes detection reactive current value and detection active current value, and the given AC parameter includes given reactive current value and given active current value. The determination of the switch control parameter of the inverter circuit according to the detection AC parameter and the corresponding given AC parameter, the detection DC parameter and the corresponding given DC parameter includes: generating active AC control parameter according to the detection active current value and the given active current value; generating reactive AC control parameter according to the detection reactive current value and the given reactive current value; determining active switch control parameter of the inverter circuit according to one of the active AC control parameter and the DC control parameter, and the switch control parameter of the inverter circuit includes the active switch control parameter and the reactive AC control parameter.

4. The method of claim 2, wherein, The determination of the switch control parameter of the inverter circuit according to one of the fourth control parameter and the target DC control parameter includes: performing minimum operation on the fourth control parameter and the target DC control parameter to obtain the switch control parameter of the inverter circuit.

5. The method of claim 1, wherein, If the inverter circuit is in the DC charging mode, the method further includes: setting the given DC voltage value to be greater than the detection DC voltage value; setting the DC charging limit current value as the given DC current value. If the inverter circuit is in the AC four-quadrant working mode, the method further includes: setting the given DC voltage value to be less than the detection DC voltage value; setting the DC charging limit current value as the given DC current value.

6. The method of claim 3, wherein, If the inverter circuit is in the DC charging mode, the method further includes: setting the given reactive current value and the given active current value to be greater than or equal to zero; If the inverter circuit is in the AC four-quadrant working mode, the method further includes: setting the given reactive current value and the given active current value to be values in a preset range.

7. An inverter circuit control device characterized by comprising: The method includes: obtaining detection AC parameter of an inverter circuit and detection DC parameter of the inverter circuit; determining switch control parameter of the inverter circuit according to the detection AC parameter and the corresponding given AC parameter, the detection DC parameter and the corresponding given DC parameter; controlling module, configured to determine switch control signal according to the switch control parameter, and the switch control signal is used for controlling a switch unit of the inverter circuit; The determination module is further configured to determine AC control parameter of the inverter circuit according to the detection AC parameter and the corresponding given AC parameter, determine DC control parameter of the inverter circuit according to the detection DC parameter and the corresponding given DC parameter, and determine the switch control parameter of the inverter circuit according to one of the AC control parameter and the DC control parameter. The detecting direct current parameters comprises detecting direct current voltage values and detecting direct current current values; the given direct current parameters comprises given direct current voltage values and given direct current current values; the determining module is further configured to determine a first control parameter of the inverter circuit according to the detecting direct current voltage values and the given direct current voltage values; determine a second control parameter of the inverter circuit according to the detecting direct current current values and the given direct current current values; perform a maximum operation on the first control parameter and the second control parameter to determine a target direct current control parameter; and determine a switch control parameter of the inverter circuit according to one of the target direct current control parameter and the alternating current control parameter. The given direct current parameters further comprises a maximum direct current voltage value; the determining module is further configured to determine a third control parameter of the inverter circuit according to the detecting direct current voltage values and the maximum direct current voltage value; and obtain the switch control parameter of the inverter circuit according to one of the third control parameter, the alternating current control parameter and the target direct current control parameter.

8. An inverter module characterized by comprising: The inverter circuit comprises: An inverter circuit and a control unit, a switch unit in the inverter circuit is connected to the control unit, and the control unit is configured to perform steps of the inverter circuit control method according to any one of claims 1 to 6.

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