Multi-VSG reactive power proportion distribution control method and device based on consistency theory

Abstract

The invention discloses a multi-VSG reactive power proportional distribution control method and device based on a consistency theory, and belongs to the technical field of network-forming type converter control, and the method comprises the steps: employing active droop control and a swing equation to carry out primary adjustment, and obtaining a primary voltage angular frequency; carrying out primary regulation by adopting reactive droop control and an integration link to obtain a primary voltage amplitude; performing secondary adjustment on the reference voltage angular frequency and the reference voltage amplitude based on a leadless consistency algorithm to obtain an active loop phase angle and a reactive loop voltage amplitude; performing dq conversion on the active loop phase angle and the reactive loop voltage amplitude, and performing dynamic virtual impedance control based on a leader consistency algorithm to obtain a dq-axis component of the voltage amplitude of the output side of the VSG converter; and performing dq inverse transformation and pulse modulation on the dq-axis component of the voltage amplitude to obtain a PWM signal for VSG converter control. According to the invention, a solid guarantee can be provided for stable operation and high-quality power supply of the VSG.

Description

Technical Field

[0001] The present invention relates to the technical field of grid-type converter control, and in particular to a multi-VSG reactive power ratio distribution control method and device based on consistency theory. Background Art

[0002] The energy transition is leading to the increasingly pronounced "double high" characteristics of power systems. Against this backdrop, virtual synchronous generator control (VSG) has emerged. However, renewable energy sources are often located in remote areas, connected to loads via long lines. Furthermore, when distributed generation (DG) is connected to medium and low voltage distribution networks, the line impedance R / X is large, making precise reactive power control difficult. Uneven reactive power distribution can cause some converters to overload, triggering overload protection. Currently, multiple VSG reactive power sharing control methods include adaptive virtual impedance control and dynamic droop coefficient control.

[0003] The adaptive virtual impedance control method offsets the voltage drop caused by the difference in feeder impedance by designing virtual resistance and virtual impedance. However, in actual engineering applications, line impedance is difficult to measure, and the reactive and active power outputs of each DG change in real time. Therefore, the dynamic adjustment performance of this control strategy is poor.

[0004] The dynamic change of the droop coefficient control method can avoid the adverse effects of real-time regulation of reactive and active power output by each DG. However, a large droop coefficient will cause the PCC point (point of common coupling) to deviate significantly from the rated voltage, affecting the power quality of the system in island mode.

[0005] Therefore, the existing multi-VSG reactive power sharing control cannot achieve both the requirements of "good dynamic regulation performance" and "good power quality" at the same time. Summary of the Invention

[0006] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a multi-VSG reactive power proportional distribution control method and device based on consistency theory, which solves the power quality problems of poor dynamic adjustment performance of traditional multi-VSG parallel reactive power sharing and PCC point voltage offset.

[0007] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0008] In a first aspect, the present invention provides a multi-VSG reactive power ratio distribution control method based on consistency theory, comprising:

[0009] Obtain the voltage angular frequency on the output side of the VSG converter, and perform a primary adjustment using active power droop control and the swing equation to obtain the primary voltage angular frequency;

[0010] Obtain the voltage amplitude on the output side of the VSG converter, and use reactive droop control and integral link to perform a primary adjustment to obtain the primary voltage amplitude;

[0011] Performing secondary adjustment on the reference voltage angular frequency and the reference voltage amplitude based on a leaderless consistency algorithm to obtain a secondary voltage angular frequency and a secondary voltage amplitude;

[0012] Obtaining an active loop phase angle and a reactive loop voltage amplitude according to the secondary voltage angular frequency and the secondary voltage amplitude;

[0013] Performing dq transformation on the active loop phase angle and the reactive loop voltage amplitude, and performing dynamic virtual impedance control based on a leader consistency algorithm to obtain the dq axis components of the voltage amplitude at the output side of the VSG converter;

[0014] The dq axis components of the voltage amplitude at the output side of the VSG converter are subjected to dq inverse transformation and pulse modulation to obtain a PWM signal for controlling the VSG converter.

[0015] Optionally, the secondary voltage angular frequency ω fi for:

[0016]

[0017] Where, ω fi , is the secondary voltage angular frequency and primary voltage angular frequency of the i-th VSG converter, ω bi is the voltage angular frequency secondary adjustment value of the i-th VSG converter;

[0018]

[0019] Where c ω is the control gain of voltage angular frequency, e ωbi is the voltage angular frequency adjustment error of the i-th VSG converter, is the voltage amplitude secondary regulation value ω bi The derivative of

[0020]

[0021] Where, ω fj is the secondary voltage angular frequency of the jth VSG converter, ω fref is the secondary voltage angular frequency reference value, N is the VSG converter set, a ij is the connection status of the i,jth VSG converter;

[0022] Secondary voltage angular frequency reference value ω fref According to the PCC point voltage angular frequency ω pccand its reference value ω pccref After the PI controller, we get:

[0023] ω fref =ω n +k p (ω pccref -ω pcc )+k i ∫(ω pccref -ω pc )dt

[0024] Where k p ,k i are the proportional coefficient and integral coefficient of the PI controller, ω n is the rated voltage angular frequency.

[0025] Optionally, the secondary voltage amplitude V fi for:

[0026]

[0027] Where V fi , is the secondary voltage amplitude and primary voltage amplitude of the i-th VSG converter, u bi is the secondary regulation value of the voltage amplitude of the i-th VSG converter;

[0028]

[0029] Where c v is the control gain of the voltage amplitude, evb i is the voltage amplitude regulation error of the i-th VSG converter, is the voltage amplitude secondary adjustment value u bi The derivative of

[0030]

[0031] Where V fj is the secondary voltage amplitude of the jth VSG converter, V fref is the secondary voltage amplitude reference value, N is the VSG converter set, a ij is the connection status of the i,jth VSG converter;

[0032] Secondary voltage amplitude reference value V fref According to the voltage amplitude V at PCC point pcc and its reference value V pccref After the PI controller, we get:

[0033] V fref =V n +k p (Vpccref -V pcc )+ k i∫(V pccref -V pcc )dt

[0034] Where k p ,k i is the proportional coefficient and integral coefficient of the PI controller, V n is the rated voltage amplitude.

[0035] Optionally, the dq-axis components of the voltage amplitude at the output side of the VSG converter obtained by performing dynamic virtual impedance control based on a leader consistency algorithm include:

[0036] Construct auxiliary control quantities for consistent coordinated synchronization of VSG converters:

[0037]

[0038] Where, is the auxiliary control quantity of the i-th VSG converter; C nQ is the control gain of reactive power, is the reactive power allocation error of the i-th VSG converter:

[0039]

[0040] Where n i ,n j is the reactive power droop control coefficient of the i,j VSG converter, Q i ,Q j is the reactive power at the output side of i,j VSG converters, N is the set of VSG converters, a ij is the connection status of the i,jth VSG converter;

[0041] The auxiliary control amount The adaptive virtual impedance is obtained by the PI controller:

[0042]

[0043] Where k p ,k i are the proportional coefficient and integral coefficient of the PI controller, and s is the Laplace variable; is the virtual impedance correction value of the i-th VSG converter; K QZ is the proportional gain coefficient, Z vi is the static virtual impedance and adaptive virtual impedance of the i-th VSG converter;

[0044] According to the adaptive virtual impedance Zvi The voltage reference for voltage-current dual closed-loop control is obtained by decoupling the dq-axis component of the voltage amplitude at the output side of the VSG converter obtained by dq transformation of the active loop phase angle and the reactive loop voltage amplitude, and serving as the final dq-axis component u of the voltage amplitude at the output side of the VSG converter. vdi ,u vqi :

[0045] Z vi =R vi +jω fi L vi

[0046]

[0047] Where R vi ,L vi is the virtual resistance and virtual inductance of the i-th VSG converter, i di ,i qi is the dq-axis component of the current amplitude at the output side of the i-th VSG converter, u di ,u qi is the dq-axis component of the voltage amplitude at the output side of the i-th VSG converter before decoupling, ω fi is the secondary voltage angular frequency of the i-th VSG converter.

[0048] In a second aspect, the present invention provides a multi-VSG reactive power proportional distribution control device based on consistency theory, comprising:

[0049] The voltage angular frequency primary regulation module is configured to obtain the voltage angular frequency at the output side of the VSG converter and perform primary regulation using active power droop control and a swing equation to obtain the primary voltage angular frequency;

[0050] The voltage amplitude primary regulation module is configured to obtain the voltage amplitude at the output side of the VSG converter and perform primary regulation using reactive power droop control and an integral link to obtain the primary voltage amplitude;

[0051] a secondary regulation module configured to perform secondary regulation on the reference voltage angular frequency and the reference voltage amplitude based on a leaderless consistency algorithm to obtain a secondary voltage angular frequency and a secondary voltage amplitude;

[0052] an intermediate variable determination module, configured to obtain an active loop phase angle and a reactive loop voltage amplitude according to the secondary voltage angular frequency and the secondary voltage amplitude;

[0053] A dynamic virtual impedance control module is configured to perform dq transformation on the active loop phase angle and the reactive loop voltage amplitude, and perform dynamic virtual impedance control based on a leader consistency algorithm to obtain the dq axis component of the voltage amplitude at the output side of the VSG converter;

[0054] The conversion and modulation module is configured to perform dq inverse conversion and pulse modulation on the dq axis components of the voltage amplitude at the output side of the VSG converter to obtain a PWM signal for controlling the VSG converter.

[0055] In a third aspect, the present invention provides an electronic device, including a processor and a storage medium;

[0056] The storage medium is used to store instructions;

[0057] The processor is configured to operate according to the instructions to execute the steps of the above method.

[0058] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the above method when executed by a processor.

[0059] In a fifth aspect, the present invention provides a computer program product, comprising a computer program / instruction, which implements the steps of the above method when executed by a processor.

[0060] Compared with the prior art, the present invention has the following beneficial effects:

[0061] The present invention provides a multi-VSG reactive power proportion distribution control method and device based on consistency theory. In the power frequency control stage, the reference voltage angular frequency is secondary adjusted based on the leaderless consistency algorithm, which overcomes the PCC point frequency offset caused by load fluctuations and improves the power quality of the system; in the excitation control stage, the reference voltage amplitude is secondary adjusted based on the leaderless consistency algorithm, which overcomes the voltage drop at the VSG converter outlet and to the PCC point caused by virtual impedance and feeder impedance, and improves the power quality of the system; in the dynamic virtual impedance control stage, the virtual resistance and virtual inductance are adjusted based on the leader consistency algorithm, so that the VSG converter can accurately output reactive power according to the capacity ratio, and the real-time adjustment of the virtual impedance improves the dynamic adjustment performance of the virtual impedance. In summary, the present invention can provide a solid guarantee for the stable operation and high-quality power supply of the VSG converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 This is a schematic diagram of the parallel connection of traditional VSG converters provided by an embodiment of the present invention;

[0063] Figure 2 This is a schematic diagram of a conventional virtual impedance-based reactive power sharing control method according to an embodiment of the present invention;

[0064] Figure 3 1 is a flow chart of a multi-VSG reactive power proportional distribution control method based on consistency theory provided by an embodiment of the present invention;

[0065] Figure 4 1 is a schematic diagram of a strategy for multi-VSG reactive power proportional distribution control based on consistency theory provided by an embodiment of the present invention;

[0066] Figure 5 Schematic diagram of a strategy for dynamic virtual impedance control based on a leader-based consensus algorithm provided by an embodiment of the present invention;

[0067] Figure 6 Schematic diagram of the structure of a two-VSG parallel simulation system provided by an embodiment of the present invention;

[0068] Figure 7 This is a waveform diagram of the active power output of the VSG converter before and after adding the adaptive virtual impedance provided by the embodiment of the present invention;

[0069] Figure 8 This is a diagram of the reactive power waveform of the VSG converter output before and after adding the adaptive virtual impedance according to an embodiment of the present invention;

[0070] Figure 9 : This is a waveform diagram of the voltage amplitude at the PCC point before and after adding secondary regulation according to an embodiment of the present invention;

[0071] Figure 10 This is a diagram of the voltage angular frequency waveform at the output side of the VSG converter before and after adding secondary regulation provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0072] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention.

[0073] Example 1:

[0074] like Figure 1 The figure shows a schematic diagram of the traditional VSG converter in parallel. The DG passes through the VSG converter, LC filter, and transmission line impedance and is connected in parallel at the PCC point to supply power to the load. Figure 1 Middle: L f 、R f and C f are the filter inductor, filter resistor and filter capacitor of the converter respectively; P i and Q i are the active power and reactive power flowing from the VSG converter to the PCC point; R i and L i They represent the transmission line between the converter and the load, V pcc is the voltage at the PCC point. In practical applications, the positions of the DGs are relatively random, which leads to different feeder impedances.

[0075] like Figure 2 As shown in FIG, it is the principle diagram of traditional reactive power sharing control based on virtual impedance. Figure 2 In the figure, the feeder impedance of DG2 is greater than that of DG1, R and X are the feeder impedances of the two DGs of the same size, and ΔR and ΔX are the transmission resistance and reactance of DG2 that are greater than those of DG1.

[0076] The traditional virtual impedance method is to design X V =-ΔX,R V =-ΔR, thereby eliminating the line voltage drop caused by the difference in feeder impedance of different lines, as shown in the following formula. However, in actual engineering applications, line impedance is difficult to measure accurately.

[0077]

[0078] Where, X v is the virtual impedance, R v is a virtual resistor, P2 and Q2 are the active and reactive power output by DG2, and U0 is the rated voltage.

[0079] Let the virtual resistance and virtual reactance be equal, that is, M v =X v =R v , we can get the virtual impedance M v for:

[0080]

[0081] In the formula In actual applications, the active and reactive power output of DG changes in real time, which also leads to The value will change, but the traditional virtual resistance and reactance cannot be adjusted in real time with the change of active and reactive power, and the addition of virtual impedance will also cause the PCC point voltage to shift.

[0082] like Figure 3 and Figure 4 As shown, the embodiment of the present invention provides a multi-VSG reactive power ratio distribution control method based on consistency theory, including the following steps:

[0083] Step S1: Obtain the voltage angular frequency at the output side of the VSG converter, and perform a primary adjustment using active power droop control and a swing equation to obtain a primary voltage angular frequency.

[0084] Step S2: Obtain the voltage amplitude at the output side of the VSG converter, and perform a primary adjustment using reactive droop control and an integral link to obtain a primary voltage amplitude.

[0085] Step S3: performing secondary adjustment on the reference voltage angular frequency and the reference voltage amplitude based on the leaderless consistency algorithm to obtain a secondary voltage angular frequency and a secondary voltage amplitude.

[0086] Among them, the secondary voltage angular frequency ω fi for:

[0087]

[0088] Where, ω fi , is the secondary voltage angular frequency and primary voltage angular frequency of the i-th VSG converter, ω bi is the voltage angular frequency secondary adjustment value of the i-th VSG converter;

[0089]

[0090] Where c ω is the control gain of voltage angular frequency, e ωbi is the voltage angular frequency adjustment error of the i-th VSG converter, is the voltage amplitude secondary regulation value ω bi The derivative of

[0091]

[0092] Where, ω fj is the secondary voltage angular frequency of the jth VSG converter, ω fref is the secondary voltage angular frequency reference value, N is the VSG converter set, a ij is the connection status of the i-th and j-th VSG converters; when the i-th and j-th VSG converters are connected, a ij =1, otherwise a ij =0;

[0093] Secondary voltage angular frequency reference value ω fref According to the PCC point voltage angular frequency ω pcc and its reference value ω pccref After the PI controller, we get:

[0094] ω fref =ω n +k p (ω pccref -ω pcc )+k i ∫(ω pccref -ω pcc )dt

[0095] Where k p ,k i are the proportional coefficient and integral coefficient of the PI controller, ω n is the rated voltage angular frequency.

[0096] Secondary voltage amplitude V fifor:

[0097]

[0098] Where V fi , is the secondary voltage amplitude and primary voltage amplitude of the i-th VSG converter, u bi is the secondary regulation value of the voltage amplitude of the i-th VSG converter;

[0099]

[0100] Where c v is the control gain of the voltage amplitude, e vbi is the voltage amplitude regulation error of the i-th VSG converter, is the voltage amplitude secondary adjustment value u bi The derivative of

[0101]

[0102] Where V fj is the secondary voltage amplitude of the jth VSG converter, V fref is the secondary voltage amplitude reference value, N is the VSG converter set, a ij is the connection status of the i,jth VSG converter;

[0103] Secondary voltage amplitude reference value V fref According to the voltage amplitude V at PCC point pcc and its reference value V pccref After the PI controller, we get:

[0104] V fref =V n +k p (V pccref -V pcc )+k i ∫(V pccref -V pcc )dt

[0105] Where k p ,k i is the proportional coefficient and integral coefficient of the PI controller, V n is the rated voltage amplitude.

[0106] Step S4: Obtain the active loop phase angle and the reactive loop voltage amplitude according to the secondary voltage angular frequency and the secondary voltage amplitude.

[0107] Specifically, in this embodiment, the secondary voltage angular frequency is transferred through the function 1 / s to obtain the active loop phase angle, and the secondary voltage amplitude is directly used as the reactive loop voltage amplitude.

[0108] Step S5: Perform dq transformation on the active loop phase angle and the reactive loop voltage amplitude, and perform dynamic virtual impedance control based on a leader consistency algorithm to obtain the dq axis components of the voltage amplitude on the output side of the VSG converter.

[0109] The dq transformation of the active loop phase angle and the reactive loop voltage amplitude includes:

[0110] Convert the active ring phase angle and reactive ring voltage amplitude into three-phase voltage:

[0111]

[0112] Where, θ and E are the phase angle of the active loop and the voltage amplitude of the reactive loop respectively;

[0113] Convert the three-phase voltage into dq axis components and 0 axis components:

[0114]

[0115] like Figure 5 As shown, the dq-axis components of the voltage amplitude at the output side of the VSG converter obtained by dynamic virtual impedance control based on the leader consensus algorithm include:

[0116] Construct auxiliary control quantities for consistent coordinated synchronization of VSG converters:

[0117]

[0118] Where, is the auxiliary control quantity of the i-th VSG converter; C nQ is the control gain of reactive power, is the reactive power allocation error of the i-th VSG converter:

[0119]

[0120] Where n i ,n j is the reactive power droop control coefficient of the i,j VSG converter, Q i ,Q j is the reactive power at the output side of i,j VSG converters, N is the set of VSG converters, a ij is the connection status of the i,jth VSG converter;

[0121] The auxiliary control amount The adaptive virtual impedance is obtained by the PI controller:

[0122]

[0123] Where k p ,ki are the proportional coefficient and integral coefficient of the PI controller, and s is the Laplace variable; is the virtual impedance correction value of the i-th VSG converter; K QZ is the proportional gain coefficient, Z vi is the static virtual impedance and adaptive virtual impedance of the i-th VSG converter;

[0124] According to the adaptive virtual impedance R vi The dq axis component of the voltage amplitude on the output side of the VSG converter obtained by dq transformation of the active loop phase angle and the reactive loop voltage amplitude is decoupled to obtain the voltage reference for the voltage and current dual closed-loop control, which is used as the dq axis component u of the voltage amplitude on the output side of the final VSG converter. vdi ,u vqi :

[0125] Z vi =R vi +jω fi L vi

[0126]

[0127] Where R vi ,L vi is the virtual resistance and virtual inductance of the i-th VSG converter, i di ,i qi is the dq-axis component of the current amplitude at the output side of the i-th VSG converter, u di ,u qi is the dq-axis component of the voltage amplitude at the output side of the i-th VSG converter before decoupling, ω fi is the secondary voltage angular frequency of the i-th VSG converter.

[0128] Step S6: Perform dq inverse transformation and pulse modulation on the dq axis components of the voltage amplitude at the output side of the VSG converter to obtain a PWM signal for controlling the VSG converter.

[0129] like Figure 6 To verify the technical effects of the present invention, a simulation system with two VSGs in parallel was built, where Z1 and Z2 represent the total impedance of the line from different VSGs to the PCC point. The parameters set during the simulation are shown in Table 1.

[0130] Table 1: Simulation parameters

[0131]

[0132]

[0133] Condition 1: The reactive power droop coefficients of the two converters are 6 Var / V and 3 Var / V, and the active power droop coefficients are 30 kW / Hz and 15 kW / Hz, respectively. The initial load is 9 kW and 3 kV. The fluctuating load of 3 kW and 1.8 kV is applied for 1 to 2 seconds, and the total simulation time is 3 seconds. The active power and reactive power before and after the addition of the adaptive virtual impedance are shown in Figure 1. Figure 7 and Figure 8 shown.

[0134] pass Figure 7 and Figure 8 It can be seen that when the two converters have different capacity configurations, the converter output active power can be distributed in inverse proportion to the droop coefficient both before and after the addition of the adaptive virtual impedance. However, the converter output reactive power cannot be distributed in inverse proportion to the droop coefficient before the addition of the adaptive virtual impedance. Only after the addition of the adaptive virtual impedance can the output reactive power Q1 and Q2 maintain a 1:2 distribution relationship.

[0135] Working condition 2: Based on working condition 1, the voltage and frequency secondary regulation with leadership consistency is added. The system frequency and PCC point voltage before and after the secondary regulation are as follows: Figure 9 and Figure 10 As shown in the figure, traditional VSG control cannot effectively handle load fluctuations and the addition of virtual impedance, causing system frequency and PCC voltage to deviate from their set values. This can affect power quality in island mode. However, the addition of the proposed consistency algorithm for secondary regulation can offset the negative impacts of load fluctuations, virtual impedance, and feeder impedance on system power quality, effectively providing secondary regulation.

[0136] In summary, the reactive power proportional distribution virtual impedance control strategy proposed in this patent has significant advantages. This strategy can flexibly and accurately adjust the virtual impedance value according to the real-time changes in reactive power on the outlet side of the VSG converter, ensuring that when multiple VSGs are operated in parallel, the reactive power can be evenly distributed strictly according to the capacity of each converter. At the same time, this patented control strategy effectively solves the voltage drop problem caused by virtual impedance and line impedance, and greatly reduces the adverse effects of load fluctuations on system frequency. By introducing a secondary regulation mechanism, the VSG control system is given a powerful self-regulation capability, significantly improving the stability of system operation. This strategy provides a strong guarantee for the stable operation of the VSG converter and good power quality.

[0137] Example 2:

[0138] An embodiment of the present invention provides a multi-VSG reactive power proportional distribution control device based on consistency theory, comprising:

[0139] The voltage angular frequency primary regulation module is configured to obtain the voltage angular frequency at the output side of the VSG converter and perform primary regulation using active power droop control and a swing equation to obtain the primary voltage angular frequency;

[0140] The voltage amplitude primary regulation module is configured to obtain the voltage amplitude at the output side of the VSG converter and perform primary regulation using reactive power droop control and an integral link to obtain the primary voltage amplitude;

[0141] a secondary regulation module configured to perform secondary regulation on the reference voltage angular frequency and the reference voltage amplitude based on a leaderless consistency algorithm to obtain a secondary voltage angular frequency and a secondary voltage amplitude;

[0142] An intermediate variable determination module is configured to obtain an active loop phase angle and a reactive loop voltage amplitude according to a secondary voltage angular frequency and a secondary voltage amplitude;

[0143] A dynamic virtual impedance control module is configured to perform dq transformation on the active loop phase angle and the reactive loop voltage amplitude, and perform dynamic virtual impedance control based on a leader consensus algorithm to obtain the dq axis components of the voltage amplitude at the output side of the VSG converter;

[0144] The conversion and modulation module is configured to perform dq inverse conversion and pulse modulation on the dq axis components of the voltage amplitude at the output side of the VSG converter to obtain a PWM signal for controlling the VSG converter.

[0145] Example 3:

[0146] Based on the multi-VSG reactive power proportional distribution control device provided in the first embodiment, an embodiment of the present invention provides an electronic device including a processor and a storage medium;

[0147] The storage medium is used to store instructions;

[0148] The processor is configured to operate according to the instructions to execute the steps of the above method.

[0149] Example 4:

[0150] Based on the multi-VSG reactive power proportional distribution control device provided in the first embodiment, an embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the above method when executed by a processor.

[0151] Embodiment 5:

[0152] Based on the multi-VSG reactive power proportional distribution control device provided in the first embodiment, an embodiment of the present invention provides a computer program product, including a computer program / instruction, which implements the steps of the above method when executed by a processor.

[0153] It will be understood by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Thus, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0154] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowcharts and / or block diagrams, as well as combinations of processes and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowcharts and / or block diagrams. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0155] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0156] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 The steps for the function specified in one or more boxes.

[0157] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A multi-VSG reactive power ratio distribution control method based on consistency theory, characterized in that: include: Obtain the voltage angular frequency on the output side of the VSG converter, and perform a primary adjustment using active power droop control and the swing equation to obtain the primary voltage angular frequency; Obtain the voltage amplitude on the output side of the VSG converter, and use reactive droop control and integral link to perform a primary adjustment to obtain the primary voltage amplitude; Performing secondary adjustment on the reference voltage angular frequency and the reference voltage amplitude based on a leaderless consistency algorithm to obtain a secondary voltage angular frequency and a secondary voltage amplitude; Obtaining an active loop phase angle and a reactive loop voltage amplitude according to the secondary voltage angular frequency and the secondary voltage amplitude; Performing dq transformation on the active loop phase angle and the reactive loop voltage amplitude, and performing dynamic virtual impedance control based on a leader consistency algorithm to obtain the dq axis components of the voltage amplitude at the output side of the VSG converter; The dq axis components of the voltage amplitude at the output side of the VSG converter are subjected to dq inverse transformation and pulse modulation to obtain a PWM signal for controlling the VSG converter.

2. The multi-VSG reactive power ratio distribution control method based on consistency theory according to claim 1 is characterized in that: The secondary voltage angular frequency ω fi for: Where, is the secondary voltage angular frequency and primary voltage angular frequency of the i-th VSG converter, ω bi is the voltage angular frequency secondary adjustment value of the i-th VSG converter; Where c ω is the control gain of voltage angular frequency, e ωbi is the voltage angular frequency adjustment error of the i-th VSG converter, is the voltage amplitude secondary regulation value ω bi The derivative of Where, ω fj is the secondary voltage angular frequency of the jth VSG converter, ω fref is the secondary voltage angular frequency reference value, N is the VSG converter set, a ij is the connection status of the i,jth VSG converter; Secondary voltage angular frequency reference value ω fref According to the PCC point voltage angular frequency ω pcc and its reference value ω pccref After the PI controller, we get: oh fref =ω n +k p (oh pccref -oh pcc )+k i ∫(ω pccref -oh pcc )dt Where k p ,k i are the proportional coefficient and integral coefficient of the PI controller, ω n is the rated voltage angular frequency.

3. The multi-VSG reactive power ratio distribution control method based on consistency theory according to claim 1 is characterized in that: The secondary voltage amplitude V fi for: Where, is the secondary voltage amplitude and primary voltage amplitude of the i-th VSG converter, u bi is the secondary regulation value of the voltage amplitude of the i-th VSG converter; Where c v is the control gain of the voltage amplitude, e vbi is the voltage amplitude regulation error of the i-th VSG converter, is the voltage amplitude secondary adjustment value u bi The derivative of Where V fj is the secondary voltage amplitude of the jth VSG converter, V fref is the secondary voltage amplitude reference value, N is the VSG converter set, a ij is the connection status of the i,jth VSG converter; Secondary voltage amplitude reference value V fref According to the voltage amplitude V at PCC point pcc and its reference value V pccref After the PI controller, we get: V fref =V n +k p (V pccref -V pcc )+k i ∫(V pccref -V pcc )dt Where k p ,k i is the proportional coefficient and integral coefficient of the PI controller, V n is the rated voltage amplitude.

4. The multi-VSG reactive power ratio distribution control method based on consistency theory according to claim 1 is characterized in that: The dq-axis components of the voltage amplitude at the output side of the VSG converter obtained by performing dynamic virtual impedance control based on a leader consistency algorithm include: Construct auxiliary control quantities for consistent coordinated synchronization of VSG converters: Where, is the auxiliary control quantity of the i-th VSG converter; C nQ is the control gain of reactive power, is the reactive power allocation error of the i-th VSG converter: Where n i ,n j is the reactive power droop control coefficient of the i,j VSG converter, Q i ,Q j is the reactive power at the output side of i,j VSG converters, N is the set of VSG converters, a ij is the connection status of the i,jth VSG converter; The auxiliary control amount The adaptive virtual impedance is obtained by the PI controller: Where k p ,k i are the proportional coefficient and integral coefficient of the PI controller, and s is the Laplace variable; is the virtual impedance correction value of the i-th VSG converter; K QZ is the proportional gain coefficient, is the static virtual impedance and adaptive virtual impedance of the i-th VSG converter; According to the adaptive virtual impedance Z vi The voltage reference for voltage-current dual closed-loop control is obtained by decoupling the dq-axis component of the voltage amplitude at the output side of the VSG converter obtained by dq transformation of the active loop phase angle and the reactive loop voltage amplitude, and serving as the final dq-axis component u of the voltage amplitude at the output side of the VSG converter. vdi ,u vqi : FROM vi =R vi +jω fi L vi Where R vi ,L vi is the virtual resistance and virtual inductance of the i-th VSG converter, i di ,i qi is the dq-axis component of the current amplitude at the output side of the i-th VSG converter, u di ,u qi is the dq-axis component of the voltage amplitude at the output side of the i-th VSG converter before decoupling, ω fi is the secondary voltage angular frequency of the i-th VSG converter.

5. A multi-VSG reactive power proportional distribution control device based on consistency theory, characterized in that: include: The voltage angular frequency primary regulation module is configured to obtain the voltage angular frequency at the output side of the VSG converter and perform primary regulation using active power droop control and a swing equation to obtain the primary voltage angular frequency; The voltage amplitude primary regulation module is configured to obtain the voltage amplitude at the output side of the VSG converter and perform primary regulation using reactive power droop control and an integral link to obtain the primary voltage amplitude; a secondary regulation module configured to perform secondary regulation on the reference voltage angular frequency and the reference voltage amplitude based on a leaderless consistency algorithm to obtain a secondary voltage angular frequency and a secondary voltage amplitude; an intermediate variable determination module, configured to obtain an active loop phase angle and a reactive loop voltage amplitude according to the secondary voltage angular frequency and the secondary voltage amplitude; A dynamic virtual impedance control module is configured to perform dq transformation on the active loop phase angle and the reactive loop voltage amplitude, and perform dynamic virtual impedance control based on a leader consistency algorithm to obtain the dq axis component of the voltage amplitude at the output side of the VSG converter; The conversion and modulation module is configured to perform dq inverse conversion and pulse modulation on the dq axis components of the voltage amplitude at the output side of the VSG converter to obtain a PWM signal for controlling the VSG converter.

6. An electronic device, characterized in that: including processor and storage medium; The storage medium is used to store instructions; The processor is configured to operate according to the instructions to execute the steps of the method according to any one of claims 1 to 4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method according to any one of claims 1 to 4 are implemented.

8. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instructions are executed by a processor, the steps of the method according to any one of claims 1 to 4 are implemented.

Images