CN108683212B - Hybrid energy storage type virtual synchronous generator control method based on power decoupling - Google Patents
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- H—ELECTRICITY
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Abstract
The invention relates to a hybrid energy storage type virtual synchronous generator control method based on power decoupling, which comprises the following steps: in a distributed power generation system controlled by adopting a virtual synchronous generator technology, a power type energy storage element and an energy type energy storage element are used for hybrid energy storage, and the energy type energy storage element is connected with a photovoltaic cell in parallel; the power type energy storage element and the energy type energy storage element are respectively and independently controlled, when the system load changes in a step mode, the output power of the power type energy storage element is controlled to show oscillation attenuation characteristics, and the parallel output power of the energy type energy storage element and the photovoltaic cell is controlled to show first-order inertia characteristics. Compared with the prior art, the virtual synchronous generator system introduces hybrid energy storage, simulates the characteristics of a static rotor and a regulating valve of a traditional generator through the hybrid energy storage, is structurally closer to the traditional synchronous generator, and realizes independent control of inertia control and primary frequency modulation control of the virtual synchronous generator.
Description
Technical Field
The invention relates to a virtual synchronous generator control method, in particular to a hybrid energy storage type virtual synchronous generator control method based on power decoupling.
Background
In recent years, with the increasing energy crisis and environmental pollution, a distributed power generation technology using renewable energy for power generation has been rapidly developed. The distributed power generation such as wind power generation, photovoltaic power generation and the like is safe, stable and efficient in grid connection, and has important significance for improving the structural form of energy and improving the operation safety of a large power grid. The traditional synchronous generator rotor has inertia to stabilize the system frequency, but the structure of the inverter system lacks a rotating body with inertia, and the rotating body can only be connected to the grid as a current source. In order to solve the problems of insufficient inertia, poor frequency stability and the like of a power grid, a distributed power supply starts to adopt a virtual synchronous generator control strategy, the power supply form of an inverter is changed by simulating a traditional synchronous generator and adopting a virtual synchronous generator technology of configuring an energy storage unit in an inverter structure, so that the inverter can show the inertia characteristic of the traditional synchronous generator, and the system frequency stability is improved to a certain extent.
However, the current virtual synchronous generator mainly focuses on the research of the inverter control algorithm, and the direct current side energy storage unit is omitted to replace the direct current bus with the direct current power supply. Due to the access of a large number of distributed power sources, the power grid has the characteristics of low inertia, poor frequency stability and the like. The single energy storage form is limited to the operating characteristics of itself, so that the virtual synchronous motor cannot simulate the conventional synchronous motor well. The energy storage units are of various types, the operating characteristics of different energy storage units are different, and aiming at hybrid energy storage, the hybrid energy storage system has the advantages that the energy density and the power density of the energy storage units are complementary, at present, partial research is already carried out on applying the hybrid energy storage system to an alternating current-direct current micro-grid to realize different power responses, and at the present stage, the type of the energy storage unit applied to the virtual synchronous motor is single, the total energy storage capacity is large, and the hybrid energy storage is not introduced aiming at the power response characteristics of the virtual synchronous motor.
Therefore, starting from the structure of the traditional synchronous motor, how to reasonably combine the multi-type energy storage form with the virtual synchronous motor has important effects on the practicability of the virtual synchronous motor and the adaptability of the virtual synchronous motor.
The method aims at the problems of energy storage unit configuration and control strategy of the virtual synchronous motor, and researches are rarely carried out at present. The virtual synchronous motor system structure is composed of new energy power generation equipment such as a photovoltaic panel, an energy storage unit and a grid-connected inverter. The new energy power generation equipment and the energy storage unit are arranged on the direct current side, and the grid-connected inverter is arranged on the alternating current side. When the system load fluctuates, the primary frequency modulation and the inertia control of the virtual synchronous motor are realized through the charge and discharge control of the energy storage unit. Therefore, the reasonable selection and configuration of the energy storage unit and the optimization of the control strategy will influence the realization of the virtual synchronous motor. In the literature, "model of virtual synchronous generator and optimal configuration of energy storage unit" (once, shaoyawa, standing, etc. power system automation, 2015(13):22-31.) analyzes mathematical model and control strategy of virtual synchronous motor in detail, under different inertia and damping parameter conditions, damping, under-damping and critical damping are divided into 3 cases, three index parameters of power, energy and dynamic response time of virtual synchronous motor additional energy storage unit optimal configuration are provided, the minimum power requirement is the amplitude of renewable energy fluctuation power required to be stabilized, and the minimum energy requirement and dynamic response time are expressions related to the inertia and damping parameters of virtual synchronous motor. However, the type of energy storage unit configured in this document is single, and the operation characteristics of the energy storage unit itself are not considered. The document "" control strategy of hybrid energy storage in wind-solar complementary microgrid "" (Zhang Xin, Sun fortune all. electric power system protection and control, 2015,43(21):93-98.) constructs a supercapacitor-battery hybrid energy storage system applied to the wind-solar complementary microgrid, and provides a control strategy based on power outer loop and current inner loop control and a DC/DC control strategy based on a moving average filter. However, the advantages of hybrid energy storage technology have been elucidated in this document, but the proposed microgrid technology is still not mature at present.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide a hybrid energy storage type virtual synchronous generator control method based on power decoupling.
The purpose of the invention can be realized by the following technical scheme:
a hybrid energy storage type virtual synchronous generator control method based on power decoupling comprises the following steps:
in a distributed power generation system controlled by adopting a virtual synchronous generator technology, a power type energy storage element and an energy type energy storage element are used for hybrid energy storage, and the energy type energy storage element is connected with a photovoltaic cell in parallel; the power type energy storage element and the energy type energy storage element are respectively and independently controlled, when the system load changes in a step mode, the output power of the power type energy storage element is controlled to show oscillation attenuation characteristics, and the parallel output power of the energy type energy storage element and the photovoltaic cell is controlled to show first-order inertia characteristics.
Preferably, the power type energy storage element is connected to the dc bus through a first bidirectional dc conversion circuit, and the first bidirectional dc conversion circuit adopts a double-loop control method of a voltage outer loop and a current inner loop.
Preferably, the double-loop control method of the voltage outer loop and the current inner loop specifically includes:
in voltage outer ring control, the difference between a voltage reference value and a measured value of a direct current bus is subjected to a PI regulator to obtain an inner ring current reference value; in the current inner loop control, the difference between the reference value of the inner loop current and the measured value of the output current of the first bidirectional direct current conversion circuit is processed by a proportional controller to obtain the duty ratio of a switching tube in the first bidirectional direct current conversion circuit.
Preferably, the energy storage element is connected to the dc bus through a second bidirectional dc conversion circuit, and the second bidirectional dc conversion circuit adopts a combined control method of a droop controller and inner loop control.
Preferably, the combined control method of the droop controller and the inner loop control specifically includes:
the output power reference value is obtained through the droop controller, the output power of the photovoltaic cell is subtracted from the output power reference value in inner loop control to obtain the output power reference value of the lead-acid cell, the output power reference value of the lead-acid cell is divided by the voltage measured value of the direct-current bus to obtain the output current reference value of the second bidirectional direct-current conversion circuit, and the difference between the output current reference value and the output current measured value of the second bidirectional direct-current conversion circuit is processed through the PI regulator to obtain the switching duty ratio of a switching tube in the second bidirectional direct-current conversion circuit.
Preferably, the power type energy storage element comprises a super capacitor.
Preferably, the energy storage element comprises a lead-acid battery.
Compared with the prior art, the invention has the following advantages:
1. the hybrid energy storage is introduced into the virtual synchronous generator system, the static rotor of the hybrid energy storage virtual traditional generator is structurally closer to the traditional synchronous generator through the characteristics of the regulating valve, corresponding control parameters of each function can be independently set, and the inertia control and the primary frequency modulation control of the virtual synchronous generator can be better controlled.
2. The lead-acid battery and the super capacitor are used for hybrid energy storage, so that the power response characteristics can be better corresponded, the power density complementation and the energy density complementation are realized, the total capacity is effectively reduced on the basis of not influencing the functions, and the investment cost is reduced.
Drawings
FIG. 1 is a schematic diagram of a conventional synchronous generator;
FIG. 2 is a schematic diagram of a conventional synchronous generator control process;
FIG. 3 is a schematic diagram of the output power and the regulator valve power of a conventional synchronous generator;
FIG. 4 is a schematic view of rotor inertial power of a conventional synchronous generator;
FIG. 5 is a comparison of charge and discharge rates of a battery;
FIG. 6 is a comparison of the battery step response;
FIG. 7 is a schematic diagram of a hybrid energy storage type virtual synchronous generator control method according to the present invention;
FIG. 8 is a schematic diagram illustrating a method for controlling an inverter in a hybrid energy storage type virtual synchronous generator according to the present invention;
FIG. 9 is an output electric power of the hybrid energy storage type virtual synchronous motor in the embodiment;
FIG. 10 is a system frequency of the hybrid energy storage type virtual synchronous machine in the embodiment;
fig. 11 shows the output power of the virtual regulating valve obtained by decoupling the power of the hybrid energy storage type virtual synchronous motor;
fig. 12 shows static rotor output power obtained by decoupling power of the hybrid energy storage type virtual synchronous motor.
Detailed Description
The invention is described in detail below with reference to the figures and specific embodiments. The present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the scope of the present invention is not limited to the following embodiments.
Firstly, decoupling analysis of power is carried out aiming at the power response of the traditional synchronous generator, and the power of the regulating valve and the inertia power of the rotor are obtained, and the process is as follows.
The traditional synchronous generator is composed of three structures, namely a regulating valve, a prime mover such as a water turbine or a steam turbine and a generator body, as shown in figure 1. The steam power or the water head power is transmitted to the prime motor through the opening degree of the regulating valve or the guide vane, the prime motor realizes the conversion of the internal energy of the steam or the potential energy of the water to the mechanical energy, the power of the rotor is input into the generator, and the generator realizes the conversion of the mechanical energy to the electric energy. By analyzing the steady-state operation characteristic and the transient state adjustment process of the traditional synchronous motor, the following characteristic equations can be obtained:
regulating valve regulation characteristic equation:
Pm＝Pref+k(ωref-ωs) (1)
equation of motion of the rotor:
electrical-power angle equation of generator:
wherein, PmTo adjust the valve power, PrefAs a reference value of load power, ωrefAt a nominal angular frequency, ωsFor the mechanical angular speed of the rotor, k is the regulating valve regulating factor, PiIs rotor inertia power, E is generator no-load electromotive force, U is generator port voltage, J is rotational inertia, D is rotor damping coefficient, and P iseTo output power, ωgridThe power grid electrical angular frequency is shown, delta is the power angle of the generator, t is time, and X is the synchronous reactance of the generator.
From the above characteristic equations, the control process of the synchronous generator obtained by using the small signal model analysis method of the synchronous generator in the conventional power system is shown in fig. 2. After modeling analysis, a transfer function between the output power and the load power reference value of the traditional synchronous motor can be obtained, and the expression is as follows:
the system transfer function equation (4) shows that the system transfer function changes with the changes of the moment of inertia J and the damping coefficient D. When the system load has step change delta PrefWhen the synchronous generator is used, the step response of the output of the traditional synchronous generator shows second-order oscillation attenuation characteristics. Because the electrical angular frequency of the power grid is determined by the angular speed of the generator rotor, and the electrical angular frequency of the power grid is approximately equal to the angular speed of the generator rotor in the transient state and the steady state, the system angular frequency approximate expression obtained by simultaneous formulas (1), (2) and (3) is as follows:
after the system angular frequency time domain expression is obtained through the arrangement, the electrical angular frequency and the rotor angular velocity show first-order inertia characteristics, the system angular frequency change rate is reduced along with the increase of the rotational inertia, and the frequency stability is improved.
When the load sudden change is responded, the opening degree of a regulating valve of the traditional synchronous generator is changed, meanwhile, the rotor outputs the inertia power of the rotor, and the two changed powers are coupled on the rotor to form mechanical power, so that the coupled mechanical power needs to be decoupled, and a theoretical basis is provided for the virtual synchronous generator hybrid energy storage type equivalent structure configuration. The analysis formula (2) can make omega because the change range of the rotor angular speed is extremely smalls≈ωrefAnd the rotor power conservation equation obtained after the arrangement is as follows:
in a conventional synchronous generator, when the angular speed of a rotor is changed, the amount of change in the angular speed is detected and converted into the opening degree of a regulating valve, thereby controlling the amount of power of the regulating valve input to a prime mover. From the governing valve characteristic equation and the rotor power equation, a governing valve power expression can be obtained as follows:
Pm＝Pref+k(ωref-ωs) (8)
when the traditional synchronous generator is analyzed to deal with sudden load changes of a power grid, the angular frequency of the system is changed due to the fact that the power of the system is unbalanced, but the rotor has large mass and large inertia, so that the angular speed of the rotor is changed slowly, and the rotational kinetic energy can be stored or released in the transient state adjusting process. Defining the inertial power of rotor as PiAnd obtaining an inertia power expression (9) by a power conservation principle and a rotor power equation (7), wherein the output power sign is positive when the rotor decelerates, and the absorption power sign is negative when the rotor accelerates.
From the above analysis, the output power response of the synchronous generator, the power expression of the regulating valve and the inertial power expression of the rotor are obtained respectively, and the power response of the regulating valve and the inertial power response of the rotor are respectively as follows:
from the above, when the conventional synchronous generator deals with the load step change, the output power shows the second-order oscillation characteristic, the regulating valve power shows the first-order inertia characteristic, and the rotor inertia power shows the oscillation attenuation characteristic. As shown in fig. 3 and 4, the dynamic response of each power of the conventional synchronous generator is shown when the load is increased in steps.
In the transient state adjustment process of the traditional synchronous generator, input power consists of regulating valve power and rotor inertia power with different characteristics, and the generator plays a role in power conversion. The power change speed of the regulating valve is low, no overshoot exists, and the requirement on the response speed is not high. The rotor inertial power responds fast while the oscillation amplitude is large, but the capacity released by the short transient time is small, so that the power density needs to be more concerned when the energy storage is configured. A secondary battery, which is one type of energy storage device, is commonly used as a power supply for dc devices or a backup power source for UPS in power systems because of its relatively low manufacturing price and low installation and maintenance costs. The energy type energy storage element, such as a lead-acid battery, has high energy density, is a storage battery with wide application, but has low power density, the charge-discharge multiplying power of the energy type energy storage element is only about 0.2C, and C is the residual capacity of the storage battery. Meanwhile, the lead-acid battery has higher requirement on the environmental temperature and less charge-discharge cycle times. The power type energy storage element, such as a super capacitor, has high power density, the charge-discharge multiplying power of the power type energy storage element can reach more than 1.5C, the power type energy storage element is often used in occasions with high requirements on dynamic response, and meanwhile, the charge-discharge cycle number is also higher.
Fig. 5 and fig. 6 show the charge and discharge rate and the power response of different types of storage batteries, respectively, and it can be seen that the charge and discharge power of the super capacitor is higher than that of the lead-acid battery and the response speed is higher under the same capacity. By the operating characteristics of the storage batteries of different types and the combination of the power response of the traditional synchronous generator, the lead-acid battery with certain capacity and the controller can be equivalent to a regulating valve as a virtual regulating valve, and the super capacitor replaces a generator rotor to serve as a static rotor. After the lead-acid battery and the hybrid energy storage unit of the super capacitor are introduced into the virtual synchronous generator, the virtual synchronous generator is equivalent to a traditional synchronous generator in structural form, and is closer to the traditional synchronous generator in response of power of different structures.
As shown in fig. 7, the present application provides a hybrid energy storage type virtual synchronous generator control method based on power decoupling according to the decoupling analysis, including:
in a distributed power generation system controlled by adopting a virtual synchronous generator technology, a power type energy storage element and an energy type energy storage element are used for hybrid energy storage, and the energy type energy storage element is connected with a photovoltaic cell in parallel; the power type energy storage element and the energy type energy storage element are respectively and independently controlled, when the system load changes in a step mode, the output power of the power type energy storage element is controlled to show the oscillation attenuation characteristic, and the parallel output power of the energy type energy storage element and the photovoltaic cell is controlled to show the first-order inertia characteristic. In fig. 7, the super capacitor and its controller are static rotors of a virtual synchronous generator, and the control process is equivalent to the rotor self-regulation process of a conventional generator, and is used for maintaining the dc bus voltage stable. The lead-acid battery is matched with the photovoltaic battery to serve as a virtual regulating valve of the virtual synchronous generator, and the output power is regulated through the system frequency difference and the droop controller.
The power type energy storage element is connected with the direct current bus through a first bidirectional direct current conversion circuit which is a BUCK/BOOST bidirectional direct current conversion circuit and is used for maintaining the voltage U of the direct current busdcAnd the voltage is kept stable at 700V, so that the power control of the power type energy storage element is automatically realized. The first bidirectional direct current conversion circuit adopts a double-loop control method of a voltage outer loop and a current inner loop, and specifically comprises the following steps:
in the voltage outer ring control, the voltage reference value U of the direct current bus is useddc ＊And the measured value UdcThe difference is processed by PI regulator to obtain reference value I of inner loop currentL ＊(ii) a In the current inner loop control, the inner loop current is referenced to the value IL ＊And the measured value I of the output current of the first bidirectional DC conversion circuitLThe difference is processed by a proportional controller to obtain the duty ratio D of a switching tube in the first bidirectional DC conversion circuit1D is1The control of the part can be realized by directly sending the voltage to the switch of the first bidirectional DC conversion circuit.
The energy type energy storage element is connected with the direct current bus through a second bidirectional direct current conversion circuit, the second bidirectional direct current conversion circuit is a BUCK/BOOST bidirectional direct current conversion circuit and is used for increasing the port voltage of the energy type energy storage element and controlling the output power of the energy type energy storage element. The second bidirectional direct current conversion circuit adopts a combined control method of a droop controller and inner loop control. The droop controller mainly uses for reference the control process of the traditional synchronous generator regulating valve (when the system load is increased, the generator rotor is decelerated, the opening of the regulating valve is linearly increased due to the action of the regulator, so that the steam flow entering the inside of a steam turbine is increased, namely, the input power is increased), and the control process can be expressed by a mathematical formula:
P*＝Pnref+kn(ωnref-ωns)
wherein, ω isnrefIs a grid angular frequency reference value, the value of which is 100 pi; omegansThe actual angular frequency of the power grid; k is a radical ofnIs the sag factor; pnrefFor rated output power of the inverter, P*Is the output power reference value, namely the total reference power of the virtual regulating valve.
Outputting a power reference value P in inner loop control*Subtracting the output power P of the photovoltaic cellpvObtaining the output power reference value P of the lead-acid batteryBAT ＊A 1 is to PBAT ＊Divided by the DC bus voltage measurement UabTo obtain the output current reference value I of the second bidirectional DC conversion circuitI ＊Is shown byI ＊And output current measurement IIThe difference is processed by a PI regulator to obtain a switching duty ratio D for controlling a switching tube in the second bidirectional DC conversion circuit2D is2The control of the part is realized by directly feeding the part into a switch of the second bidirectional direct current conversion circuit.
The port of a photovoltaic cell (PV) is connected with a DC/DC direct current conversion circuit, the DC/DC circuit adopts a boost circuit, and the purpose is to promote the voltage value of the port of the PV cell to the voltage value of a direct current bus and realize MPPT (maximum power point tracking) control of the PV cell. The partial control structure of the photovoltaic cell is shown in fig. 7, and the power reference value P of the photovoltaic cell can be obtained through MPPTpv ＊By comparison with the actual output power P of the photovoltaic cellpvAfter comparison, the boost is obtained through the adjustment of a PI regulatorDuty cycle D of t boost circuit3Will duty ratio D3The control of the part can be realized by directly sending the part to a switching tube of a boost circuit.
The power type energy storage element adopts a Super Capacitor (SC) or other energy storage elements with higher power density and lower energy density. The energy type energy storage element adopts a lead acid Battery (BAT) or other energy storage elements with higher energy density and longer inertia time.
Examples
Simulation parameters are as in table 1:
table 1 simulation parameter settings
| Parameter(s) | Value taking |
| DC bus voltage Udc | 700V |
| Rated photovoltaic output PPV | 50kW |
| Load fluctuation amplitude Δ Pref | 30kW |
| Lead-acid battery rated capacity Sn1 | 150kW·h |
| Rated capacity S of super capacitorn2 | 15kW·h |
| Regulating valve regulating coefficient k | 23874 |
| Moment of inertia | 1kg·m2 |
The virtual synchronous generator system starts to stably operate with 50kW of output electric power, when t is 2s, the load is suddenly increased by 30kW to 80kW, and as can be seen from FIG. 9, the virtual synchronous generator system can effectively follow the change of the load power, and simultaneously the output electric power response shows the second-order oscillation attenuation characteristic. Fig. 10 shows a comparison between the improvement conditions of the virtual synchronous generators with different moments of inertia on the system frequency when the load of the power grid changes, and it can be seen that the virtual synchronous generators can effectively improve the system frequency and improve the stability of the frequency by comparing the droop control strategy without the inertia control link. Meanwhile, as can be seen from fig. 10, as the moment of inertia increases, the system frequency becomes more stable.
The virtual synchronous generator system with the static rotor and the virtual regulating valve, which is proposed by the method, outputs power through structures, as shown in fig. 11 and 12. When the load suddenly increases by 30kW to 80kW at t ═ 2s, the virtual regulator valve output power P 'is as shown in fig. 11'mThe first-order inertia characteristic is shown, and the response speed is slow. The output power value under the steady state is equal to the output power value of the virtual synchronous motor system, and the characteristic is consistent with the characteristic of a regulating valve of a traditional synchronous motor. Fig. 12 shows the static rotor power of a virtual synchronous machine system, which can be seen to exhibit an oscillation damping characteristic with a faster response speed than a virtual governor valve. The steady state output value is 0, and the rotating speed of the rotor is constant similarly to the rotating speed of the rotor when the traditional synchronous motor runs in a steady state. The static and dynamic characteristics of the static rotor are consistent with those of the traditional synchronous motor rotor.
Claims (1)
1. A hybrid energy storage type virtual synchronous generator control method based on power decoupling is characterized by comprising the following steps:
in a distributed power generation system controlled by adopting a virtual synchronous generator technology, a power type energy storage element and an energy type energy storage element are used for hybrid energy storage, and the energy type energy storage element is connected with a photovoltaic cell in parallel; the power type energy storage element, the energy type energy storage element and a controller thereof are respectively and independently controlled, the power type energy storage element is equivalent to a static rotor of a virtual synchronous motor, the energy type energy storage element and the controller thereof are matched with a photovoltaic cell equivalent virtual regulating valve, when the system load is subjected to step change, the output power of the power type energy storage element is controlled to show oscillation attenuation characteristics, and the parallel output power of the energy type energy storage element and the photovoltaic cell is controlled to show first-order inertia characteristics;
the power type energy storage element is connected with a direct current bus through a first bidirectional direct current conversion circuit, and the first bidirectional direct current conversion circuit adopts a double-loop control method of a voltage outer loop and a current inner loop;
the double-loop control method of the voltage outer loop and the current inner loop specifically comprises the following steps: in voltage outer ring control, the difference between a voltage reference value and a measured value of a direct current bus is subjected to a PI regulator to obtain an inner ring current reference value; in the current inner loop control, the difference between an inner loop current reference value and an output current measurement value of the first bidirectional direct current conversion circuit is processed by a proportional controller to obtain the duty ratio of a switching tube in the first bidirectional direct current conversion circuit;
the energy type energy storage element is connected with a direct current bus through a second bidirectional direct current conversion circuit, and the second bidirectional direct current conversion circuit adopts a combined control method of a droop controller and inner ring control;
the combined control method of the droop controller and the inner loop control specifically comprises the following steps: obtaining an output power reference value through a droop controller, subtracting the output power of a photovoltaic cell from the output power reference value in inner loop control to obtain an output power reference value of a lead-acid battery, dividing the output power reference value of the lead-acid battery by a direct current bus voltage measured value to obtain an output current reference value of a second bidirectional direct current conversion circuit, and enabling the difference between the output current reference value and the output current measured value of the second bidirectional direct current conversion circuit to pass through a PI regulator to obtain a switching duty ratio for controlling a switching tube in the second bidirectional direct current conversion circuit;
the power type energy storage element comprises a super capacitor;
the energy storage element comprises a lead-acid battery.
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| CN110880794B (en) * | 2019-12-11 | 2021-02-26 | 华中科技大学 | Power distribution method and device of hybrid energy storage virtual synchronous generator |
| WO2021173136A1 (en) * | 2020-02-27 | 2021-09-02 | General Electric Company | System and method for control of hybrid renewable energy storage system |
| CN112186797A (en) * | 2020-09-10 | 2021-01-05 | 南京国电南自电网自动化有限公司 | Damping control method and device for virtual synchronous machine and storage medium |
| FR3114452B1 (en) * | 2020-09-22 | 2023-06-30 | Electricite De France | METHOD FOR CONTROLLING A GENERATOR SYSTEM AND CONTROLLED GENERATOR SYSTEM ACCORDING TO THIS METHOD |
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