A method and system for coordinated control of a grid-forming SVG and energy storage converter

Abstract

The application relates to the technical field of network-constructing energy storage, and provides a network-constructing SVG and energy storage converter coordinated control method and system, which comprises the following steps: obtaining PCC network side reactive power, carrying out difference between the reactive power and a given value, obtaining an alternating current voltage given value through a reactive power controller; obtaining an SVG direct current side voltage, carrying out difference between the SVG direct current voltage and a reference value, obtaining an SVG frequency through a proportional controller, and outputting a phase angle through an integral element; for the alternating current voltage given value, a voltage-current double loop control is carried out to obtain a modulation voltage, the modulation voltage and the phase angle are used to generate a three-phase PWM driving signal to control an SVG converter; the SVG direct current side voltage is obtained, difference between the SVG direct current voltage and the reference value is carried out, a proportional differential controller is used to obtain a PCS active power reference value, and a three-phase PWM driving signal is generated through PCS power current double closed loop control to control a PCS converter. The frequency regulation capability is possessed.

Description

Technical Field

[0001] This invention belongs to the field of grid-type energy storage technology, and particularly relates to a coordinated control method and system for grid-type SVG and energy storage converter. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] The construction of new power systems has led to a gradual increase in the penetration rate of new energy sources such as wind and solar power. These energy forms, using power electronic converters as interfaces, replace equipment such as synchronous generators with physical rotational inertia as the main power source of the power system, reducing the inertia level of the power system. On the other hand, new energy power generation is mostly aimed at obtaining maximum power, resulting in external characteristics that exhibit grid-connected current source form, making it unable to participate in frequency regulation. The high proportion of new energy significantly affects the inertia response of the power system, reduces frequency regulation capability, and disrupts frequency stability.

[0004] Grid-based energy storage exhibiting voltage source characteristics can solve the above problems. It integrates virtual inertia elements and can participate in the frequency regulation of the power system, thereby improving the frequency inertia level.

[0005] However, grid-based energy storage is still in the technological development stage, and its engineering applications are not yet mature. Power Conversion Systems (PCS) still mostly adopt grid-based control. Recently, the development of grid-based control capabilities for Static Var Generators (SVG) has become a research hotspot. Unlike PCS, grid-based SVG cannot provide active power to the power system; it can only participate in the inertial response stage of the power system frequency, lacking capabilities such as primary frequency regulation. Summary of the Invention

[0006] To address the technical problems mentioned above, this invention provides a coordinated control method and system for grid-connected SVG and energy storage converter. By introducing a proportional-derivative control loop at the outermost layer of the PCS grid-connected control strategy, the steady-state transfer gain from the DC side voltage of the SVG to the active power generated by the VSG is no longer zero, thereby enabling the grid-connected SVG and energy storage hybrid system to have frequency regulation capability.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: The first aspect of the present invention provides a coordinated control method for a grid-type SVG and an energy storage converter, comprising: The reactive power on the PCC grid side is obtained, and the difference between it and the reactive power setpoint is used to obtain the AC voltage setpoint through the reactive power controller; the DC voltage on the SVG side is obtained, and the difference between it and the SVG DC voltage reference value is used to obtain the SVG frequency through the proportional controller, and the phase angle is output through the integral stage; for the AC voltage setpoint, the modulation voltage is obtained through voltage-current dual-loop control, and together with the phase angle, a three-phase PWM drive signal is generated through coordinate transformation to control the SVG converter; The DC side voltage of the SVG is obtained, and the difference between it and the DC voltage reference value of the SVG is used to obtain the active power reference value of the PCS through a proportional-derivative controller. The PCS power current dual closed-loop control is used to generate a three-phase PWM drive signal to control the PCS converter.

[0008] Furthermore, it also includes: obtaining the active power generated by the VSG, subtracting it from the given value of the active power of the VSG, and then obtaining the actual power system frequency through the inertial controller.

[0009] Furthermore, the value of the VSG active power setpoint is set to achieve a PCC network-side power factor of 1.

[0010] Furthermore, the SVG frequency control forward channel gain is: ;in, V c This indicates the effective value of the PCC phase voltage. V g This indicates the effective value of the VSG phase voltage. δ This indicates the power angle at which the PCC voltage lags behind the VSG voltage. X line Indicates the inductive reactance of the transmission line. C SVG The DC capacitor of the SVG is [capacitor name], and the DC voltage of the SVG is [voltage values]. v dc1 , K vp and D vp These represent the proportional coefficient and the differential coefficient, respectively. G ( s ) represents the transfer function.

[0011] A second aspect of the present invention provides a coordinated control system for a grid-type SVG and an energy storage converter, comprising: The SVG grid-type control module is configured to: acquire the reactive power of the PCC grid side, subtract it from the reactive power setpoint, and then pass it through the reactive power controller to obtain the AC voltage setpoint; acquire the DC voltage of the SVG, subtract it from the DC voltage reference value of the SVG, and then pass it through the proportional controller to obtain the SVG frequency, and output the phase angle through the integral stage; for the AC voltage setpoint, obtain the modulation voltage through voltage-current dual-loop control, and together with the phase angle, generate a three-phase PWM drive signal through coordinate transformation to control the SVG converter; The PCS and grid-type control module are configured to: acquire the DC side voltage of the SVG, subtract it from the DC voltage reference value of the SVG, and then obtain the active power reference value of the PCS through a proportional-derivative controller; generate a three-phase PWM drive signal through the PCS power current dual closed-loop control to control the PCS converter.

[0012] Furthermore, it also includes: obtaining the active power generated by the VSG, subtracting it from the given value of the active power of the VSG, and then obtaining the actual power system frequency through the inertial controller.

[0013] Furthermore, the value of the VSG active power setpoint is set to achieve a PCC network-side power factor of 1.

[0014] Furthermore, the SVG frequency control forward channel gain is: ;in, V c This indicates the effective value of the PCC phase voltage. V g This indicates the effective value of the VSG phase voltage. δ This indicates the power angle at which the PCC voltage lags behind the VSG voltage. X line Indicates the inductive reactance of the transmission line. C SVG The DC capacitor of the SVG is [capacitor name], and the DC voltage of the SVG is [voltage values]. v dc1 , K vp and D vp These represent the proportional coefficient and the differential coefficient, respectively. G ( s ) represents the transfer function.

[0015] A third aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-described coordinated control method for a grid-type SVG and energy storage converter.

[0016] A fourth aspect of the present invention provides a computer device including a computer-readable storage medium, a processor, and a computer program stored on the computer-readable storage medium and executable on the processor, wherein the processor executes the program to implement the steps of the coordinated control method for a grid-type SVG and energy storage converter as described above.

[0017] Compared with the prior art, the beneficial effects of the present invention are: This invention introduces a proportional-derivative control loop at the outermost layer of the PCS grid-connected control strategy, so that the steady-state transfer gain from the DC side voltage of the SVG to the active power generated by the VSG is no longer 0, thus enabling the grid-connected SVG and energy storage hybrid system to have frequency regulation capability.

[0018] This invention uses proportional-derivative control to increase frequency damping. The SVG frequency control loop behaves as a type I system, thus frequency oscillations can be suppressed. Attached Figure Description

[0019] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0020] Figure 1 This is a frequency control principle diagram of Embodiment 1 of the present invention; Figure 2 This is a power system architecture diagram according to Embodiment 1 of the present invention; Figure 3 This is a flowchart of the coordinated control of the grid-type SVG and energy storage converter in Embodiment 1 of the present invention; Figure 4 This is a frequency waveform diagram under coordinated control according to Embodiment 1 of the present invention; Figure 5 This is a frequency waveform diagram under no-coordination control in Embodiment 1 of the present invention; Figure 6 This is a voltage and current waveform diagram under coordinated control according to Embodiment 1 of the present invention; Figure 7 This is a voltage and current waveform diagram under uncoordinated control in Embodiment 1 of the present invention; Figure 8 This is a DC voltage waveform diagram under coordinated control according to Embodiment 1 of the present invention; Figure 9 This is a DC voltage waveform diagram under uncoordinated control according to Embodiment 1 of the present invention; Figure 10 This is a power waveform diagram under coordinated control according to Embodiment 1 of the present invention; Figure 11 This is a power waveform diagram under uncoordinated control in Embodiment 1 of the present invention; Figure 12This is a schematic diagram of the structure of a computer device according to Embodiment 4 of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0022] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0023] Example 1 This embodiment provides a method for coordinated control of a grid-type SVG and an energy storage converter.

[0024] This embodiment provides a coordinated control method for grid-connected SVG and energy storage converter. It makes full use of the existing grid-connected energy storage converters in the power system and, through simple improvements to their control strategies, integrates them with the grid-connected SVG to jointly improve the power system's frequency inertia response and frequency regulation capabilities.

[0025] like Figure 2 As shown, the voltage and frequency of the power system are constructed based on a Virtual Synchronous Generator (VSG) to generate voltage. v gabc and angular frequency ω g =2π f g ,in, f g This refers to the grid-side frequency; the VSG outputs active power. p g A portion of this active power is absorbed by a frequency-independent resistive load (the active power absorbed by the resistive load has a frequency of...). p Lg Another portion is transmitted to the SVG and PCS sides (the active frequency transmitted to the SVG and PCS sides is...). p gc VSG and SVG are connected via line impedance. To simplify the analysis, the line resistance is ignored, and only the line inductance is considered. L line The current flowing through the line inductance is expressed as i gabc The SVG and PCS are connected in parallel at the point of common coupling (PCC), where the voltage and frequency are defined as follows: vcabc and ω c =2π f c ,in, f c The converter-side frequency; the PCC point receives the active power transmitted from the transmission line. p cg A portion flows to the SVG (the active power flowing to the SVG is...) p c1 The remaining portion is absorbed by the PCS (the active power absorbed by the PCS is...). p c2 The corresponding currents for the two are respectively i abc1 and i abc2 There is a filter inductor on the connection line between the PCC point and the SVG. L f1 There is a filter inductor on the connection line between PCC point and PCS. L f2 The port voltages of SVG and PCS are respectively v mabc1 and v mabc2 The DC voltages of SVG and PCS are respectively v dc1 and V dc2 The DC capacitance of the SVG is C SVG .

[0026] This embodiment provides a coordinated control method for a grid-type SVG and an energy storage converter, based on the following frequency control principle: like Figure 2 As shown, the active power at point PCC p cg With reactive power q cg It can be represented as: (1); in, V c This indicates the effective value of the PCC phase voltage. V g This indicates the effective value of the VSG phase voltage. δ This indicates the power angle at which the PCC voltage lags behind the VSG voltage. X line =2π fL line Indicates the inductive reactance of the transmission line. f It represents the steady-state frequency of the power system.

[0027] The active power balance equation at point PCC can be expressed as: (2); The relationship between the active power on the AC side of the SVG and the DC voltage is as follows: (3).

[0028] Figure 1 The principle of power system frequency control was demonstrated, in which... p c2ref and p gref These represent the active power setpoints for PCS and VSG, respectively, using prefixes. The first letter capitalized indicates the steady-state component of the relevant variable; traditional PCS uses grid-based constant active power control, based on the power setpoint. p c2ref arrive p c2 The transfer function is defined as G ( s ).

[0029] According to equations (1) and (3), we can obtain Figure 1 The transfer functions represented by (ii) and (iii) require a positive correlation in frequency control (iv) of the meshed SVG to satisfy the loop negative feedback condition and support the frequency. When the PCS and SVG operate independently, the transfer function (vi) is 0, therefore the forward channel gain of the SVG frequency control is... H 1( s ) can be represented as the product of (i), (ii), and (iii): (4); This involves two integral terms. To reduce the risk of frequency oscillations, (iv) proportional-derivative control is typically used to increase frequency damping. At this point, when the power system is in steady state, [the following occurs]. v dc1 arrive p g The transmission gain (vii) is 0, which will not affect the steady-state frequency of the power system. Therefore, the grid-type SVG does not have frequency regulation capability.

[0030] Based on the network-type SVG control, in order to enable the SVG+PCS hybrid system to have frequency regulation capability, this embodiment... v dc1 and pc2ref Establish a positive correlation control relationship between them, such as Figure 1 The proportional-derivative control (vi) shown is as follows, where K vp and D vp These represent the proportional coefficient and the differential coefficient, respectively.

[0031] Improved SVG frequency control forward channel gain H 2( s )for: (5); in, s This represents the complex frequency of the Laplace transform.

[0032] Equation (5) shows that the improved SVG frequency control loop behaves as a type I system, thus frequency oscillations can be suppressed; on the other hand, the introduced proportional-derivative control element (vi) makes the frequency oscillations... v dc1 arrive p g The steady-state transfer gain (vii) is no longer 0, thus enabling the grid-type SVG and energy storage hybrid system to have frequency regulation capability. Therefore, in this embodiment, based on the grid-type SVG control strategy, only proportional-derivative control (vi) needs to be added to the outermost layer of the PCS and grid control strategy to enable the SVG+PCS hybrid system to simultaneously possess inertial response and frequency regulation capability.

[0033] To enable the SVG+PCS hybrid system to support AC voltage, this embodiment establishes a control relationship between reactive power and voltage based on the aforementioned frequency control approach; considering the reactive power compensation requirements of the power system, a setpoint for the reactive power on the PCC grid side is set. q cg_ref =0, the reactive power controller uses a PI controller. In summary, this embodiment provides a coordinated control method for a grid-type SVG and energy storage converter, such as... Figure 3 As shown, it mainly includes three parts: frequency control, SVG reactive power-AC voltage control, and PCS DC voltage-active power control, specifically including the following steps: Step 1: SVG (Static Var Generator) grid-based control strategy, used to construct virtual grid voltage and frequency support.

[0034] Step 101: In terms of SVG reactive power-AC voltage control, real-time acquisition of PCC grid-side reactive power. q cg Compare it with the reactive power setpoint q cg_refAfter differential calculation, the voltage is passed through a reactive power controller (PI controller) and compared with the effective value of the phase voltage of the PCC phase voltage reference value. V cref By summing, we obtain the AC voltage setpoint. V c .

[0035] To achieve a PCC grid-side power factor of 1, the reactive power setpoint needs to be set to... q cg_ref =0.

[0036] in, V c It will be used as the SVG voltage and current dual closed-loop control command value.

[0037] Step 102: In terms of frequency control, this includes both the frequency control of the power system and the frequency control of the SVG.

[0038] (1) In terms of frequency control of the power system: the frequency of the power system f g Built based on VSG principles, such as Figure 1 As shown, the specific implementation steps are as follows: Real-time acquisition of the active power emitted by the VSG. p g Compare it with the VSG active power setpoint p gref After subtraction, the actual power system frequency is obtained through the inertial controller shown in (viii). f g .

[0039] Wherein, transitive relation (viii) is represented as It describes the inertial element in VSG control. K gf and T gf Representing the proportionality coefficient and the inertial time constant, respectively, the transitivity (viii) describes p gref -p g with f g The quantitative relationship between them is used to calculate the frequency value.

[0040] (2) Regarding the frequency control of the SVG: Real-time acquisition of the DC side voltage of the SVG. v dc1 Compare it with the SVG DC voltage reference value V dc1_ref After the difference is calculated, it is passed through the proportional controller (iv). K cf and frequency reference value f ref Sum to obtain the SVG control frequencyf c To enable SVG control frequency f c pass Figure 3 The integrator (2π / s) outputs the phase angle. θ c The data is sent to the SVG for dq / abc transformation, thereby enabling frequency control of the SVG.

[0041] Figure 2 In the above, (i), (ii), (iii), (v), and (vii) are all transfer functions of the controlled object in frequency control.

[0042] Regarding frequency control of SVG: power system frequency f g and SVG control frequency f c After subtraction, the result is passed through the transfer function (i), i.e., 1 / s The power angle at which the PCC voltage lags behind the VSG voltage is obtained. δ Through the transfer function (ii), i.e. The active power at point PCC is obtained. p cg Active power at point PCC p cg Active power absorbed by PCS p c2 By subtracting the values, we obtain the active power flowing to the SVG. p c1 Through the transfer function (iii), i.e. The DC side voltage of the SVG is obtained. v dc1 Among them, 1 / s The transfer function of the integrator can be obtained by taking the Laplace transform of the integrator.

[0043] Regarding frequency control in power systems: SVG DC-side voltage v dc1 By passing function The active power setpoint of the PCS is obtained. p c2ref By passing function G ( s The active power absorbed by the PCS is obtained. p c2 .

[0044] Regarding frequency control in power systems: SVG DC-side voltage v dc1 Gain is transferred through steady-state transfer (vii), i.e. The active power flowing to the SVG is obtained as follows: p c1 Among them, transitive relation (vii) is actually the reciprocal of transitive relation (iii).

[0045] Regarding frequency control in the power system: the active power flowing to the SVG is p c1 and the active power absorbed by the PCS p c2 Summing, we obtain the active power generated by the VSG. p g .

[0046] Step 103: Voltage-current dual-loop control.

[0047] Voltage loop: given value V c With respect to the d-axis component of the PCC phase voltage V cd After the difference is calculated, the voltage controller outputs the d-axis current command i. d Similarly, the q-axis component of the phase voltage of phase 0 and PCC V cq After the difference is calculated, the voltage controller outputs the q-axis current command i. q ; Current loop: Current command and measured current i d1 i q1 The error is processed by the current controller, feedforward compensation circuit, and K. PWM After the circuit, a three-phase PWM drive signal is generated through the inverse park transformation to control the SVG converter.

[0048] Step 2: PCS (converter) and grid control strategy, used to track grid commands to achieve active / reactive power transmission.

[0049] Step 201: In terms of PCS DC voltage-active power control, the DC side voltage of the SVG is collected in real time. v dc1 Compare it with the SVG DC voltage reference value v dc1_ref After difference, it is passed through a proportional-derivative controller ( K vp + sD vp The reference value for PCS active power control is obtained. p c2ref This part also corresponds Figure 2 The link (vi) in the middle. p c2ref will be as Figure 3 Command values ​​for the dual closed-loop control of power and current in the PCS.

[0050] Step 202: PCS power and current dual closed-loop control.

[0051] PCS active power control reference values ​​(PCS active power reference values) p c2ref Active power absorbed by PCS p c2 After subtraction, the current command of the PCS converter d-axis is obtained through the power controller; Current loop: PCS converter d-axis current command and measured current i d2 0 and measured current i q2 The error is processed by the current controller, feedforward compensation circuit, and K. PWM After the circuit, a three-phase PWM drive signal is generated through the inverse park transformation to control the PCS converter.

[0052] Note that in this embodiment, the signs and meanings of the PCS active power reference value and the given value are different. The given value is represented as... p c2ref .

[0053] This embodiment was built in the MATLAB / Simulink environment. Figure 2 The power system architecture shown is used to verify the effectiveness of the proposed coordinated control strategy. The parameters shown in Table 1 are used for verification. The simulation process lasts for 30 seconds. t =15s, the frequency-independent load increases from 1MW to 1.5MW, and the power system frequency is obtained ( Figure 4 and Figure 5 ), PCC voltage and current ( Figure 6 and Figure 7 ), SVG DC voltage ( Figure 8 and Figure 9 The waveform of active power absorbed by the PCS ( Figure 10 and Figure 11 This includes the dynamic waveform corresponding to coordinated control, as well as the dynamic waveform corresponding to the transfer function (vi) without considering the transfer function, that is, there is no coordinated control relationship between the network-type SVG and the PCS.

[0054] Table 1. Power System Verification Parameters

[0055] Among them, V g Indicates the effective value of the VSG phase voltage; f ref Indicates the frequency reference value; P gref K represents the setpoint of the active power of the power grid. gf and T gf These represent the proportional coefficient and the inertial time constant of the transitivity (viii), respectively; p LgK represents the active frequency absorbed by the resistive load. vp and D vp L represents the proportional coefficient and differential coefficient of the transitive relation (vi), respectively; line Indicates line inductance; L f1 / L f2 These represent the filter inductors of SVG and PCS, respectively; C SVG V is the DC capacitor of the SVG. dc1 K represents the DC voltage of the SVG in steady state. cf Indicates proportional controller (iv); P c2ref This represents the setpoint of the PCS active power.

[0056] Depend on Figure 4 and Figure 5 It can be seen that under the coordinated control strategy, the power system frequency oscillation is well suppressed during load changes. When the coordinated control strategy of SVG and PCS is not adopted, the power system frequency lacks damping due to the presence of two integral elements in the SVG frequency control loop gain, resulting in obvious oscillations during dynamic processes.

[0057] Depend on Figure 6 and Figure 7 It can be seen that regardless of whether a coordinated control strategy is adopted, the power factor between the PCC voltage and current is close to 1, indicating that the grid-type SVG can support voltage and frequency while also taking into account reactive power compensation function.

[0058] Figure 8 and Figure 9 Further evidence shows that when a coordinated control strategy is adopted, the damping level of the power system is high, thus effectively suppressing both frequency oscillations and voltage oscillations.

[0059] Figure 10 and Figure 11 The results show that when a coordinated control strategy is adopted, the active power absorbed by the PCS changes with the frequency, thus the SVG+PCS system has frequency regulation capability.

[0060] Example 2 This embodiment provides a coordinated control system for a grid-type SVG and an energy storage converter, including: The SVG grid-type control module is configured to: acquire the reactive power of the PCC grid side, subtract it from the reactive power setpoint, and then pass it through the reactive power controller to obtain the AC voltage setpoint; acquire the DC voltage of the SVG, subtract it from the DC voltage reference value of the SVG, and then pass it through the proportional controller to obtain the SVG frequency, and output the phase angle through the integral stage; for the AC voltage setpoint, obtain the modulation voltage through voltage-current dual-loop control, and together with the phase angle, generate a three-phase PWM drive signal through coordinate transformation to control the SVG converter; The PCS and grid-type control module are configured to: acquire the DC side voltage of the SVG, subtract it from the DC voltage reference value of the SVG, and then obtain the active power reference value of the PCS through a proportional-derivative controller; generate a three-phase PWM drive signal through the PCS power current dual closed-loop control to control the PCS converter.

[0061] Furthermore, it also includes: obtaining the active power generated by the VSG, subtracting it from the given value of the active power of the VSG, and then obtaining the actual power system frequency through the inertial controller.

[0062] Furthermore, the value of the VSG active power setpoint is set to achieve a PCC network-side power factor of 1.

[0063] Furthermore, the SVG frequency control forward channel gain is: ;in, V c This indicates the effective value of the PCC phase voltage. V g This indicates the effective value of the VSG phase voltage. δ This indicates the power angle at which the PCC voltage lags behind the VSG voltage. X line Indicates the inductive reactance of the transmission line. C SVG The DC capacitor of the SVG is [capacitor name], and the DC voltage of the SVG is [voltage values]. v dc1 , K vp and D vp These represent the proportional coefficient and the differential coefficient, respectively. G ( s ) represents the transfer function.

[0064] It should be noted that each module in this embodiment corresponds one-to-one with each step in Embodiment 1, and their specific implementation processes are the same, so they will not be repeated here.

[0065] Example 3 This embodiment provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps in the coordinated control method for a grid-type SVG and energy storage converter as described in Embodiment 1 above.

[0066] Example 4 This embodiment provides a computer device, such as... Figure 12As shown, the system includes a computer-readable storage medium 1003, a processor 1001, a communication interface 1002, and a computer program stored on the computer-readable storage medium 1003 and executable on the processor 1001. The processor 1001, communication interface 1002, and computer-readable storage medium 1003 can be connected via a bus or other means. The communication interface 1002 is used to receive and transmit data. When the processor 1001 executes the program, it implements the steps in the coordinated control method for a grid-type SVG and energy storage converter as described in Embodiment 1 above.

[0067] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for coordinated control of a grid-type SVG and an energy storage converter, characterized in that, include: The reactive power on the PCC grid side is obtained, and the difference between the reactive power setpoint and the setpoint is used to obtain the AC voltage setpoint through the reactive power controller. The DC side voltage of the SVG is obtained, and the difference between it and the DC voltage reference value of the SVG is used to obtain the SVG frequency through a proportional controller. The phase angle is output through an integral stage. For the AC voltage setpoint, the modulation voltage is obtained through voltage-current dual-loop control. Together with the phase angle, a three-phase PWM drive signal is generated through coordinate transformation to control the SVG converter. The DC side voltage of the SVG is obtained, and the difference between it and the DC voltage reference value of the SVG is used to obtain the active power reference value of the PCS through a proportional-derivative controller. The PCS power current dual closed-loop control is used to generate a three-phase PWM drive signal to control the PCS converter.

2. The coordinated control method for a grid-type SVG and energy storage converter as described in claim 1, characterized in that, Also includes: The active power generated by the VSG is obtained, and the difference between the active power of the VSG and the given value is used to obtain the actual power system frequency through the inertial controller.

3. The coordinated control method for a grid-type SVG and energy storage converter as described in claim 2, characterized in that, The value of the VSG active power setpoint is set so that the power factor on the PCC network side is 1.

4. The coordinated control method for a grid-type SVG and energy storage converter as described in claim 1, characterized in that, The SVG frequency control forward channel gain is: ;in, V c This indicates the effective value of the PCC phase voltage. V g This indicates the effective value of the VSG phase voltage. δ This indicates the power angle at which the PCC voltage lags behind the VSG voltage. X line Indicates the inductive reactance of the transmission line. C SVG The DC capacitor of the SVG is given, and the DC voltage of the SVG is given as follows: v dc1 , K vp and D vp These represent the proportional coefficient and the differential coefficient, respectively. G ( s ) represents the transfer function.

5. A coordinated control system for a grid-type SVG and energy storage converter, characterized in that, include: The SVG grid-type control module is configured to: acquire the reactive power of the PCC grid side, subtract it from the reactive power setpoint, and then pass it through the reactive power controller to obtain the AC voltage setpoint; acquire the DC voltage of the SVG, subtract it from the DC voltage reference value of the SVG, and then pass it through the proportional controller to obtain the SVG frequency, and output the phase angle through the integral stage; for the AC voltage setpoint, obtain the modulation voltage through voltage-current dual-loop control, and together with the phase angle, generate a three-phase PWM drive signal through coordinate transformation to control the SVG converter; The PCS and grid-type control module is configured to: acquire the DC side voltage of the SVG, subtract it from the DC voltage reference value of the SVG, and then obtain the active power reference value of the PCS through a proportional-derivative controller; generate a three-phase PWM drive signal through the PCS power current dual closed-loop control to control the PCS converter.

6. The coordinated control system for a grid-type SVG and energy storage converter as described in claim 5, characterized in that, Also includes: The active power generated by the VSG is obtained, and the difference between the active power of the VSG and the given value is used to obtain the actual power system frequency through the inertial controller.

7. The coordinated control system for a grid-type SVG and energy storage converter as described in claim 6, characterized in that, The value of the VSG active power setpoint is set so that the power factor on the PCC network side is 1.

8. The coordinated control system for a grid-type SVG and energy storage converter as described in claim 5, characterized in that, The SVG frequency control forward channel gain is: ;in, V c This indicates the effective value of the PCC phase voltage. V g This indicates the effective value of the VSG phase voltage. δ This indicates the power angle at which the PCC voltage lags behind the VSG voltage. X line Indicates the inductive reactance of the transmission line. C SVG The DC capacitor of the SVG is given, and the DC voltage of the SVG is given as follows: v dc1 , K vp and D vp These represent the proportional coefficient and the differential coefficient, respectively. G ( s ) represents the transfer function.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps in the coordinated control method of the grid-type SVG and energy storage converter as described in any one of claims 1-4.

10. A computer device comprising a computer-readable storage medium, a processor, and a computer program stored on the computer-readable storage medium and executable on the processor, characterized in that, When the processor executes the program, it implements the steps in the coordinated control method of a grid-type SVG and energy storage converter as described in any one of claims 1-4.

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