JP2020043688A - Voltage control type virtual synchronous machine control device and voltage control type virtual synchronous machine - Google Patents

Abstract

To provide a voltage control type virtual synchronous machine control device and a voltage control type virtual synchronous machine which can suppress overcurrent as maintaining voltage control type virtual synchronous machine control in a converter equipped with the voltage control type virtual synchronous machine control.SOLUTION: A voltage control type virtual synchronous machine control device performs voltage control type virtual synchronous machine control to a converter, and is equipped with a control part which performs the voltage control type virtual synchronous machine control, in which the control part is equipped with compensation means for compensating an output voltage command value to be input in the control part, the compensation means converts the output voltage command value and a measured system voltage value into a rotary coordinate system consisting of a D axis and a Q axis, uses a control circle with a radius r centering on the system voltage value as a limiter, and considers the compensated output voltage command value existing on the control circle or its inside as the output voltage command value on condition that the output voltage command value is outside the control circle.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a voltage controlled virtual synchronous machine control device and a voltage controlled virtual synchronous machine.

  In recent years, due to environmental issues, the introduction of distributed power sources using natural energy such as solar power generation systems into the grid has been progressing, and it is expected that the number will increase further in the future. When renewable energy is systemized, it is often connected via a converter. For this reason, when the renewable energy increases, the number of synchronous machines connected to the grid decreases, and as an alternative, the number of converters increases.

FIG. 11 shows a block diagram of current control based on general vector control as such a converter. The illustrated power control is a method in which a three-phase AC state quantity is converted into a two-phase (αβ conversion) and further converted into a rotating coordinate system (DQ conversion). Since the D axis (effective part) and the Q axis (ineffective part) are controlled separately and independently, both can be made non-interfering. Regarding power control, different control is used for each application of the device, but the illustrated one shows a block of constant power control that outputs constant power of _Port .

FIG. 12 is a block diagram of a PLL (phase locked loop). Thus, calculates the difference Δθ between the phase theta _S and PLL phase theta _PLL and the system voltage (primary voltage transducers transformer), control is performed so that the difference to zero.

  The converter controlled in this way has a current control system, and can suppress overcurrent even at the time of system disturbance.

  However, if many converters controlled in this way are connected to the system, problems such as an increase in system voltage fluctuation, a decrease in the amount of inertial energy in the system, a frequency change width during system disturbance, and an increase in speed will occur. Can occur. Therefore, virtual synchronous machine control has been proposed in which a converter behaves in the same manner as a conventional synchronous machine to stabilize the system (for example, see Non-Patent Document 1).

  As a converter having such a virtual synchronous machine control (hereinafter, sometimes referred to as a virtual synchronous machine), there is a converter having a voltage-controlled virtual synchronous machine control. FIG. 13 is a schematic diagram in which a virtual synchronous machine having the voltage-controlled virtual synchronous machine control is connected to a system. As shown in the figure, a virtual synchronous machine (VSG) 01 is controlled so as to simulate a behavior when a synchronous generator to be simulated is connected to a system. Note that the inductance 02 in FIG. 13 is obtained by replacing the reactor component of the generator to be simulated with the interconnection reactor of the converter.

Here, the behavior of the synchronous generator to be simulated is realized by solving the following equation.

Where P _order is the power command value, P _mes is the converter output power, J is the moment of inertia of the simulated generator, ω _m is the rotor angular velocity of the simulated generator, δ is the slip of the simulated generator, and D is the simulated power generation. Indicates the braking coefficient of the machine.

  FIG. 14 shows an example of control based on the solution of the above equation.

  Since such a voltage-controlled virtual synchronous machine operates as a voltage source by controlling a voltage, the current cannot be controlled. For this reason, an overcurrent may be generated at the time of system disturbance or the like, and the converter may be stopped. For example, when a system failure occurs near the virtual synchronous machine 01 having an inductance 02 of 0.2 pu in FIG. 13, an overcurrent of 5.0 pu or more is expected to occur. The virtual synchronous machine 01 whose concept is itself a converter cannot withstand such a large current.

Kenichi Sakimoto et al., "Stabilization Control of Grid Including Inverter-Linked Distributed Power Supply Using Virtual Synchronous Generator", IEEJ Transactions on Electronics, B, Vol.

  In a converter equipped with the conventional virtual synchronous machine control, when there is a risk of occurrence of overcurrent such as at the time of system disturbance, it is necessary to stop the voltage control type virtual synchronous machine control and perform current control. Since the control of the virtual synchronous machine is stopped, the stability of the system is adversely affected.

  In view of such circumstances, the present invention provides a voltage-controlled virtual synchronous machine capable of performing overcurrent suppression while maintaining the voltage-controlled virtual synchronous machine control in a converter including the voltage-controlled virtual synchronous machine control. An object of the present invention is to provide a control device and a voltage controlled virtual synchronizer.

  A first aspect of the present invention that achieves the above object is a voltage-controlled virtual synchronous machine control device that performs voltage-controlled virtual synchronous machine control on a converter, wherein the control performs voltage-controlled virtual synchronous machine control. A control unit, wherein the control unit includes compensation means for compensating an output voltage command value input to the control unit, wherein the compensation means converts the output voltage command value and the measured system voltage value into D. Converted to a rotating coordinate system consisting of an axis and a Q axis, using a control circle having a radius r centered on the system voltage value as a limiter, on condition that the output voltage command value goes out of the control circle, A voltage-controlled virtual synchronous machine control device is characterized in that a compensated output voltage command value existing on or inside the control circle is used as the output voltage command value.

  A second aspect of the present invention is the voltage-controlled virtual synchronous machine control device according to the first aspect, wherein the compensated output command value is a point on the control circle and close to the system voltage. It is in.

  According to a third aspect of the present invention, the radius r is a value obtained from a reactor component value of a simulation generator simulated by the voltage-controlled virtual synchronous machine control, According to a second aspect, there is provided the voltage-controlled virtual synchronous machine control device.

In a fourth aspect of the present invention, when the voltage difference V _diff between the vector vV _order of the output voltage command value and the vector vV _sys of the system voltage value is larger than r, the compensating means is configured to output the command value of the output voltage command value. V _order and the determining the compensation output voltage vector _{vV conv-rev} to and a voltage value _{V conv} entering the control circle or inside thereof lying between the system voltage value _{V sys,} the compensation output voltage vector _{vV Conv-} The voltage-controlled virtual synchronous machine control device according to any one of the first to third aspects, wherein _rev is the corrected output voltage command value.

A fifth aspect of the present invention, the compensation output voltage vector _{vV conv-rev} is, the control and vector _{vV order} of the output voltage command value _{V order,} the straight line connecting the vector _{vV sys} of the system voltage value _{V sys} A voltage-controlled virtual synchronous machine control device according to a fourth aspect, wherein the vector is a vector to an intersection with a circle.

A sixth aspect of the present invention, the compensation output voltage vector _{vV conv-rev} is, the output of the two intersection points of the straight line and the control circle extended vector _{vV sys} or the vector of the system voltage value _{V sys} A voltage-controlled virtual synchronous machine control device according to a fourth aspect, wherein the vector is a vector indicating a voltage value close to the voltage command value V _order .

  According to a seventh aspect of the present invention, there is provided a voltage-controlled virtual synchronous machine comprising a converter including the voltage-controlled virtual synchronous machine control device according to any one of the first to sixth aspects. .

  ADVANTAGE OF THE INVENTION According to this invention, in the converter provided with the voltage control type virtual synchronous machine control, the voltage control type virtual synchronous machine control apparatus and the voltage control which can perform overcurrent suppression, maintaining the voltage control type virtual synchronous machine control Type virtual synchronous machine can be realized.

FIG. 2 is a block diagram of a voltage-controlled virtual synchronous machine control device of the voltage-controlled virtual synchronous machine according to the first embodiment. FIG. 4 is an explanatory diagram conceptually showing control of a compensation control unit according to the first embodiment. FIG. 2 is a control block diagram of the voltage-controlled virtual synchronous machine control device according to the first embodiment. FIG. 9 is an explanatory diagram conceptually showing control of a compensation control unit according to the second embodiment. The schematic diagram of the analysis target system of the analysis object used for the simulation of the test example. FIG. 9 is an explanatory diagram for explaining an averaging model for a converter used for simulation for simplification. The figure which shows the waveform display location of an instantaneous value simulation result. The figure which shows the 3LG sequence and 1LG sequence used in the simulation. The figure which shows the simulation result of a 3LG sequence. The figure which shows the simulation result of 1LG sequence. FIG. 2 is a block diagram of current control based on general vector control. FIG. 2 is a block diagram of a PLL. The schematic diagram which connected the virtual synchronous machine provided with the voltage control type virtual synchronous machine control to the system. FIG. 3 is a block diagram showing an example of virtual synchronous machine control based on the solution of the equation.

  Hereinafter, the present invention will be described in detail based on embodiments.

(Embodiment 1)
FIG. 1 is a block diagram of a voltage-controlled virtual synchronous machine control device for a voltage-controlled virtual synchronous machine according to Embodiment 1 of the present invention. The voltage-controlled virtual synchronous machine control device is incorporated in a general converter to function as a converter having a voltage-controlled virtual synchronous machine control for suppressing an overcurrent. Since the converter itself is the same as the conventional one, the description here is omitted.

  As shown in FIG. 1, the voltage-controlled virtual synchronous machine control device 1 includes a voltage-controlled virtual synchronous machine control unit 10 and a compensation control unit 20.

The voltage-controlled virtual synchronous machine control unit 10 has the same configuration as a control unit that performs general voltage-controlled virtual synchronous machine control, and includes a virtual synchronous machine voltage command value vector vV _order and a rotor phase of the virtual synchronous machine. It has a coordinate conversion unit 11 that receives a corner and converts the coordinates, and a PWM control unit 12 that determines the duty ratio of the pulse width control based on the coordinate-converted data. In the present embodiment, an adder 13 is provided before the coordinate transformation unit 11.

The compensation control unit 20 receives the measured system voltage vector vV _sys and the virtual synchronous machine voltage command value vector vV _order , obtains a voltage difference V _diff between the two, and also obtains the system voltage vector vV _sys and the virtual synchronous machine voltage command value. An intersection of a straight line connecting the vector vV _order and a control circle S having a radius r centered on the system voltage vector vV _sys is defined as a corrected output voltage vector vV _conv-rev , and a virtual synchronous machine voltage command value vector vV _order is defined as a starting point. It comprises a compensation voltage calculation unit 21 for obtaining a compensation voltage vector vV _occ having the compensation output voltage vector vV _conv-rev as an end point and outputting the compensation voltage vector vV _occ , and a switch element 22. The switch element 22 is turned off when the voltage difference V _diff obtained by the compensation voltage calculation unit 21 is equal to or smaller than the radius r of the control circle, does not output anything to the adder 13, and the voltage difference V _diff is is controlled to output a compensation voltage vector vV _occ is output from the compensation voltage calculation unit 21 is turned on to the adder 13 is greater than the radius r of the control circle.

Accordingly, when the voltage difference V _diff is equal to or smaller than the radius r of the control circle, nothing is output from the compensation control unit 20 to the adder 13, and the virtual synchronous machine voltage command value vector vV _order is used as it is as the coordinates. Input to the converter 11, the virtual synchronous machine voltage command value vector vV _order becomes the output voltage V _{conv of} the voltage-controlled virtual synchronous machine as it is, while if the voltage difference V _diff is larger than the radius r of the control circle, compensation is performed. since the compensation voltage vector _{vV occ} is output from the voltage calculating portion 21 is output to the adder 13, compensation virtual synchronous machine voltage command value vector _{vV order} voltage vector _{vV occ} is summed compensated output voltage vector _{vV Conv- rev} is output to the coordinate conversion unit 11 as a compensated output command value. As a result, the compensated output voltage vector vV _conv-rev is the output voltage V _{conv of the} voltage controlled virtual synchronous machine.

  The above control is schematically shown in FIG.

FIG. 2 shows a system voltage vector vV _sys and a virtual synchronous machine voltage command value vector vV _order obtained by converting the output voltage command value and the measured system voltage value into a rotating coordinate system including the D axis and the Q axis on the rotating coordinate axis. And shows a control circle S having a radius r and centered on the system voltage value which is the end point of the system voltage vector vV _sys . The radius r is a preset value. The DQ conversion is performed on the basis of the rotor phase of the virtual synchronous machine, and the virtual synchronous machine voltage command value vector vV _order always exists on the D axis.

FIG. 2A shows that the system is relatively normal, the voltage difference V _diff between the system voltage vector vV _sys and the virtual synchronous machine voltage command value vector vV _order is small, and the virtual synchronous machine voltage command value vector vV _order is output as it is. This shows a state where the voltage becomes _Vconv .

In FIG. 2B, the system is disturbed, the voltage difference V _diff between the system voltage vector vV _sys and the virtual synchronous machine voltage command value vector vV _order becomes large, and the virtual synchronous machine voltage command value vector vV _order becomes the control circle. In this case, the _corrected output voltage vector vV _conv-rev obtained by adding the _corrected voltage vector vV _oc to the virtual synchronous machine voltage command value vector vV _order is output to the coordinate conversion unit 11, and as a result, the correction is performed. It shows a state in which the output voltage vector vV _conv-rev is controlled to be the output voltage V _{conv of the} voltage-controlled virtual synchronous machine.

Here, the control in the compensation control unit 20 will be described more specifically.
First, a difference V _diff between the virtual synchronous machine voltage command value V _order and the absolute value of the system voltage V _sys is calculated.

V _diff = | V _order −V _sys |

Next, when the absolute value difference V _diff exceeds r, the compensation voltages V _dcor and V _qcor are added to the virtual synchronous machine voltage command value V _order . The compensation voltages V _dcor and V _qcor correspond to the compensation voltage vector _vVocc-rev .

The compensation voltages V _dcor and V _qcor added at this time are _{determined based} on the virtual synchronous machine voltage command value V _order so that the final output voltage V _{conv of the} voltage controlled virtual synchronous machine falls within the control circle S. _The correction is performed in the _sys direction. As specific values, the following compensation voltages V _dcor and V _qcor are _added to the D-axis and Q-axis voltages, respectively.

Equation (1) for _calculating the compensation voltages V _dcor and V _qcor (the D-axis voltage and the Q-axis voltage of the virtual synchronous machine voltage command value V _order , respectively) is as follows.

V _dcor = (V _dsys -V _order ) × (V _diff -r) / V _{diff
V qcor = V qsys × (V} diff -r) / V diff ··· (1)

  FIG. 3 shows an example of a control block diagram of the voltage-controlled virtual synchronous machine control device including the compensation control unit 20 according to the first embodiment.

FIG. 3 is obtained by adding control via the compensation control unit 20 instead of the virtual synchronous machine voltage command value V _order in the control block diagram of FIG. As shown in the figure, the compensation voltage calculation unit 21 receives the system voltage values V _dsys and V _qsys , the radius r of the control circle S and the virtual synchronous machine voltage command value V _order, and calculates the compensation voltage from the above equation (1). V _docc and V _qoc are obtained and output. The switch element 22 is controlled by the voltage compensation flag F _diff and outputs compensation voltages V _docc and V _qoc in the on state, and outputs 0 in the off state. Here, if V _diff > r, it turns on at 1; if V _diff ≤r, it turns off at 0. The adder 13, the switch element 22 is turned on, the virtual synchronous machine voltage command value _{V order} the compensation voltage _{V DocC, V Qocc} and an addition to _{V Dconv,} outputs _{V QCONV,} the switch element 22 is OFF state , _And outputs the virtual synchronous machine voltage command value V _order as V _dconv and V _qconv as they are.

In the example of FIG. 3, the radius r of the control circle S is variable, and is changed by the overcurrent flag F _{oc so} that the converter current becomes r ₁ if the converter current is equal to or less than the threshold, and r ₂ if the converter current exceeds the threshold.

In the compensation control unit 20 described above, the compensation voltage calculation unit 21 always calculates the compensation voltage vector vV _occ and outputs the compensation voltage vector vV _occ. Only when the voltage difference V _diff is larger than the radius r, the voltage control type virtual synchronous machine is used. was designed to output a compensation voltage vector _{vV occ} to the adder 13 of the control unit 10, correction control is not limited to this, the voltage difference _{V diff} seek compensation voltage vector _{vV occ} only if larger radius r, This may be output.

Further, when the virtual synchronous machine voltage command value vector vV _order is compensated by the voltage-controlled virtual synchronous machine control unit 10, the compensated voltage vector _vVocc is added by the adder 13 to the virtual synchronous machine voltage command value vector vV _order. However, the present invention is not limited to this. If compensation is required, the compensation output voltage vector vV _conv-rev is output from the compensation control unit 20 and replaced with the virtual synchronous machine voltage command value vector vV _order . Thus, the _corrected output voltage vector vVconv _-rev may be input to the coordinate conversion unit 11.

  Further, the configuration of the voltage-controlled virtual synchronous machine control unit 10 is not particularly limited, and may be any as long as it performs conventionally known voltage-controlled virtual synchronous machine control.

  Further, the radius r of the control circle S is determined depending on how much overcurrent is to be suppressed. However, the radius r is determined by referring to the reactor component value of the simulated generator simulated by the voltage-controlled virtual synchronous machine control. Is preferred.

  For example, when the reactor value is R (pu), it is preferable that r = R ± 20%.

  Further, the radius r may not be a fixed value and may be changed according to the state of the system.

(Embodiment 2)
In the above-described embodiment, the compensated output voltage vector vV _conv-rev is the intersection of the control circle S with the straight line connecting the system voltage vector vV _sys and the virtual synchronous machine voltage command value vector vV _order , but is not limited to this. It is not something to be done. This embodiment shows another example of the compensated output voltage vector vV _conv-rev .

FIG. 4 shows the compensated output voltage vector vVconv _-rev of the present embodiment. As shown, the adjusting an output voltage vector _{vV conv-rev} of the present embodiment, the output voltage command value of the two intersection points of the straight line and the control circle S was extended vector _{vV sys} or the vector of the system voltage value _{V sys} This is a vector indicating a voltage value close to V _order .

This embodiment is basically the same as the first embodiment except that the compensated output voltage vector vV _conv-rev is changed, and the virtual synchronous machine voltage command value vector vV _order goes out of the control circle S. In this case, the corrected output voltage vector vV _conv-rev is output, and a duplicate description will be omitted.

The specific calculation of the compensated output voltage vector vVconv _{-rev in} the present embodiment is as follows.

In the case of FIG. 4, the virtual synchronous machine voltage command value V _order is extended in the direction of the system voltage value V _sys from the zero point so that the virtual synchronous machine voltage command value V _order falls within the control circle S. As specific values, the following compensation voltages V _dcor and V _qcor are _added to the D-axis and Q-axis voltages, respectively.

V _dconv = V _dsys × (| V _sys | + | r |) / | V _sys |
_{V qconv = V qsys × (|} V sys | + | r |) / | V sys |

The method of determining the compensated output voltage vector vV _conv-rev is not limited to this, and may be a compensated output voltage vector vV _conv-rev that falls within the control circle S. It is preferable that the voltage value within the control circle S be as close as possible to the virtual synchronous machine voltage command value V _order from the viewpoint of compensation while the control circle S is used. Further, for the purpose of compensation, it is preferable that the voltage value is close to the virtual synchronous machine voltage command value V _order within the control circle S between the virtual synchronous machine voltage command value V _order and the system voltage value V _sys .

(Test example)
In order to verify the effect of the present invention, operation verification by instantaneous value simulation was performed. The simulation was performed using an instantaneous value analysis program, XTAP (eXpandable Transient Analysis Program).

  FIG. 5 shows a schematic diagram of an analysis target system used in the simulation. As the converter equipment provided with the virtual synchronous machine control, one having an ideal voltage source connected to the converter DC side is used. Originally, various equipment such as a battery, a distributed power source, and other AC systems via a DC power transmission network is assumed on the converter DC side. These facilities were idealized for the purpose of verifying only suppression, and replaced with ideal voltage sources.

  The AC system includes a voltage source simulating an infinite bus, a resistor and a reactor simulating a short-circuit capacity. Here, the short-circuit capacity ratio was set to 6.93 for two lines. The accident point on the AC side was near the converter, and the AC accident was eliminated by opening the accident line with a circuit breaker.

  Note that the converter uses an averaging model to simplify the calculation. The averaging model is a model that does not simulate switching as in the detailed converter model shown in FIG. 6A, but averages ripples using a switching cycle as an averaging section as shown in FIG. 6B. It is. In addition to the reduction in the circuit scale, the calculation time can be extended in increments, and the effect of reducing the amount of calculation is high.

  Table 1 shows various conditions used for the calculation. FIG. 7 shows the waveform display locations of the instantaneous value simulation results. In this simulation, each system disturbance is implemented by controlling three patterns. Note that with overcurrent control is a model of the first embodiment, and the control circle S is that of the first embodiment.

Case a: No overcurrent suppression control
Case b: With overcurrent suppression control (radius r of control circle S is fixed at 0.2pu)
Case c: With overcurrent suppression control (radius r of control circle S in steady state is 0.2 pu, radius r when overcurrent occurs exceeding 1.2 pu is 0.1 pu)

  FIG. 8A shows a sequence of a three-phase ground fault (3LG). The time from the occurrence of 3LG to the opening of the AC circuit breaker is set to 0.1 second (5 cycles). AC accidents are eliminated by opening accident lines.

  FIG. 8B shows a one-phase ground fault (1LG) sequence. The time from the occurrence of 1 LG to the opening of the AC circuit breaker is set to 0.1 second (5 cycles). The AC accident is eliminated by opening the accident line, and at this time, the accident line is opened for all three phases.

  9 and 10 show the results of the simulation performed under the above conditions.

FIG. 9 is an enlarged view of V _sys and I _conv when 3LG occurs, and (a) to (c) correspond to Cases a to c described above. In the absence of the overcurrent suppression control of (a), a maximum of 9.19 pu overcurrent flowed in the converter (converter current rating of 1458 Apeek), whereas the cases (b) and (c) of case b, In the case where the overcurrent suppression control of c was performed, the respective values were 1.58 pu and 1.37 pu, and the overcurrent suppression effect was confirmed.

FIG. 10 is an enlarged view of V _sys and I _conv when one LG occurs, and (a) to (c) correspond to Cases a to c described above. When there is no overcurrent suppression control of (a), an overcurrent of a maximum of 2.94 pu flows through the converter. On the other hand, when overcurrent suppression control of case b and c is performed, 1.64 pu, It was 1.45 pu, and an overcurrent suppressing effect was confirmed.

REFERENCE SIGNS LIST 1 voltage-controlled virtual synchronous machine control device 10 voltage-controlled virtual synchronous machine control unit 11 coordinate conversion unit 12 PWM control unit 13 adder 20 compensation control unit 21 compensation voltage calculation unit 22 switch element

Claims (7)

A voltage-controlled virtual synchronous machine control device that performs voltage-controlled virtual synchronous machine control on a converter,
A control unit that performs voltage control type virtual synchronous machine control is provided,
The control unit includes a compensation unit that compensates an output voltage command value input to the control unit,
The compensation means converts the output voltage command value and the measured system voltage value into a rotating coordinate system including a D axis and a Q axis, and uses a control circle having a radius r centered on the system voltage value as a limiter. Voltage control characterized in that the output voltage command value is out of the control circle, and a compensated output voltage command value existing on or inside the control circle is the output voltage command value. Type virtual synchronous machine controller.   The voltage-controlled virtual synchronous machine control device according to claim 1, wherein the compensation output command value is a point on the control circle and close to the system voltage value.   3. The voltage-controlled virtual synchronous machine according to claim 1, wherein the radius r is a value obtained from a reactor component value of a simulated generator simulated by the voltage-controlled virtual synchronous machine control. Control device. When the voltage difference V _diff between the vector vV _order of the output voltage command value and the vector vV _sys of the system voltage value is larger than r, the compensating means is configured to output the output voltage command value V _order and the system voltage value V _sys and a voltage value _{V conv} and the determined control circle or compensate the output voltage vector _{vV conv-rev} entering inside, the compensation output voltage command value of this compensation output voltage vector _{vV conv-rev} located between the The voltage-controlled virtual synchronous machine control device according to any one of claims 1 to 3, wherein It said compensation output voltage vector _{vV conv-rev} is, is the vector to the intersection of the vector _{vV order} of the output voltage command value _{V order,} and the straight line and the control circle connecting the vector _{vV sys} of the system voltage value _{V sys} 5. The voltage controlled virtual synchronous machine control device according to claim 4, wherein: Said compensation output voltage vector _{vV conv-rev} is, the system voltage value the voltage value close to the output voltage command value _{V order} of the two intersections between the vector _{vV sys} or linear and the control circle extending the vector of _{V sys} The voltage-controlled virtual synchronous machine control device according to claim 4, wherein the vector is a vector indicating the following.   A voltage-controlled virtual synchronous machine, comprising: a converter including the voltage-controlled virtual synchronous machine control device according to claim 1.

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