CN112769138A - AC-DC mutual aid control device and method for AC-DC hybrid power distribution network junction converter - Google Patents
AC-DC mutual aid control device and method for AC-DC hybrid power distribution network junction converter Download PDFInfo
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/02—Circuit arrangements for ac mains or ac distribution networks using a single network for simultaneous distribution of power at different frequencies; using a single network for simultaneous distribution of ac power and of dc power
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/04—Circuit arrangements for ac mains or ac distribution networks for connecting networks of the same frequency but supplied from different sources
- H02J3/06—Controlling transfer of power between connected networks; Controlling sharing of load between connected networks
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/12—Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
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- H02J3/24—Arrangements for preventing or reducing oscillations of power in networks
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/20—The dispersed energy generation being of renewable origin
- H02J2300/22—The renewable source being solar energy
- H02J2300/24—The renewable source being solar energy of photovoltaic origin
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J2300/00—Systems for supplying or distributing electric power characterised by decentralized, dispersed, or local generation
- H02J2300/20—The dispersed energy generation being of renewable origin
- H02J2300/28—The renewable source being wind energy
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- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
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Abstract
The control device comprises a power control outer ring and a voltage and current double ring, wherein the power control outer ring comprises a direct current voltage ring, an alternating current active ring and an alternating current reactive ring, and the alternating current active ring and the alternating current reactive ring are based on a control mode of a virtual synchronous machine and are used for providing frequency response inertia characteristics for a power grid; the direct current voltage loop obtains a direct current power instruction in a direct current voltage drooping mode, and simultaneously feeds the direct current power instruction to a d axis of the voltage inner loop in a feedforward mode and feeds the direct current power instruction back to the alternating current active loop; and the voltage and current double-ring inner ring control is realized, the voltage ring generates dq axis reference current by adopting a dq decoupling control mode, three-phase current reference values are obtained through dq inverse transformation, and the current ring adopts a dead-beat control mode, so that the three-phase current tracks the current reference values in real time and is used for realizing the tracking of output voltage. The invention improves the control precision and the electric energy quality of the output voltage of the equipment and considers the rapidity and the accuracy of direct current power response.
Description
Technical Field
The invention belongs to the technical field of power grid hubs, and relates to an alternating current and direct current mutual aid control device and method for a hub converter of an alternating current and direct current hybrid power distribution network.
Background
In a traditional power system, the droop characteristic and the large moment of inertia of a synchronous generator set play a key role in maintaining the voltage and frequency stability of the system. The first stage in the process of adjusting the system frequency of the generator set is that the generator set adjusts the rapid power fluctuation of the system by means of the rotational inertia of the generator set; when the frequency fluctuation exceeds a certain limit, the frequency is adjusted by changing the prime mover power input, i.e. primary frequency modulation.
With the permeability of distributed new energy such as photovoltaic energy, wind power and the like being higher and higher, the traditional control mode has greater and greater threat to the power grid, so that the friendly grid connection of the energy becomes a problem to be solved urgently. The frequency regulation of the generator set has good reference significance for distributed power generation. Alternating current and direct current power grids in a direct current distribution network system are mutually supported as power supplies, the droop characteristic and the rotary inertia are provided by utilizing the bidirectional flow of the energy of the alternating current and direct current system to simulate the characteristic of a synchronous generator set, namely, a virtual synchronous generator technology is adopted, so that the virtual synchronous generator participates in the frequency and voltage regulation process like a generator set, the alternating current system is supported by the energy supply of the direct current power grid when the transient fluctuation occurs in the alternating current system, and the alternating current and direct current transient power mutual aid is realized.
The alternating current and direct current power mutual aid control for the alternating current and direct current hybrid distribution network is characterized in that power response control for direct current voltage fluctuation is added on the basis of a virtual synchronous machine control strategy, so that an alternating current and direct current interconnection converter has power response capability for alternating current and direct current ends, and has power response capability for active-frequency modulation and reactive-voltage regulation on an alternating current side; meanwhile, the device has the capacity of supporting active power for the direct-current voltage fluctuation on the direct-current side.
Disclosure of Invention
In order to solve the problems in the prior art, the invention aims to provide an alternating current-direct current mutual aid control device and method for a terminal converter of an alternating current-direct current hybrid power distribution network.
The invention adopts the following technical scheme:
an AC-DC mutual aid control device of a junction converter of an AC-DC hybrid power distribution network comprises a power control outer ring and a voltage-current double ring,
the power control outer ring comprises a direct current voltage ring, an alternating current active ring and an alternating current reactive ring, the alternating current active ring and the alternating current reactive ring provide frequency response inertia characteristics for a power grid under the control of the virtual synchronous machine, the direct current voltage ring obtains a direct current power instruction through the droop of direct current voltage, and the direct current power instruction is fed forward to a voltage inner ring d shaft of the voltage ring and the alternating current active ring;
an alternating current active ring in the power control outer ring generates a phase angle part of reference voltage, an alternating current reactive ring generates an amplitude part of the reference voltage, and the phase angle part and the amplitude part jointly form three-phase reference voltage; the three-phase reference voltage passes through a voltage and current double ring, so that the output voltage of the AC-DC hybrid power distribution network junction converter tracks the reference voltage;
the voltage and current double rings comprise voltage rings and current rings, wherein the voltage rings generate dq-axis reference currents in a dq decoupling control mode, three-phase current reference values are obtained through dq inverse transformation, and the current rings enable the three-phase currents to track the current reference values in real time by adopting deadbeat control so as to realize tracking of output voltages.
The topological structure of the AC-DC hybrid power distribution network junction converter is MMC, and the relation between the output voltage and the output current of the MMC is discretized to obtain the following relation:
wherein n is a discretized variable, uoa、uob、uocFor MMC equivalent output three-phase voltage ua、ub、ucFor the MMC three-phase terminal voltage, L1Is an MMC equivalent reactance, ioaOutputting three-phase current, T, for MMCsIs a control cycle.
The target reference output current reference value is used for replacing the current value at the next moment, and the dead beat coefficient is added to obtain the dead beat relational expression of the current loop as follows:
kc＝kdeadL1/Ts
wherein k iscIs the current loop coefficient, kdeadIs a dead beat coefficient.
K isdeadThe value of (a) is in the range of 0 to 1.
AC-DC mutual aid control system side voltage usd、usqThe relationship after dq transformation is as follows:
wherein u isd、uqIs the MMC terminal voltage u under dq coordinate systemsd、usqIs the system side voltage, i, in dq coordinate systemod、ioqIs an output current, L, in dq coordinate system2ω is the angular frequency of the sampled voltage for the system equivalent reactance.
Carrying out dq decoupling control on a feedforward coupling term existing in a voltage loop, wherein the decoupling target formula is as follows:
wherein f isc(s) is the current loop transfer function, s is the variable operator in the Lass transform, L2Omega is the angular frequency of the sampled voltage, u, for the system equivalent reactanced1、uq1For dq-axis voltage offset control quantity, upid、upiqAnd the pi output value is the deviation of the voltage of the dq axis MMC terminal from the target value voltage.
The virtual synchronous machine control comprises an active control loop, and the expression of the active control loop is as follows:
wherein, ω is the angular frequency of the sampled voltage; omega0Is the rated angular frequency; kP/ωIs the active frequency modulation coefficient; psetIs an active power set value; pDCrefThe value is a direct current active power regulating value; prefIs the total reference power of the active loop; p is system sampling active power; d is a system virtual damping coefficient; js is a virtual moment of inertia; omegavsgIs the virtual angular frequency.
The virtual synchronous machine control comprises a reactive power control loop, and the expression of the reactive power control loop is as follows:
Evsg＝E0+kQ(kQ/E(E0-E)+Qset-Q)
wherein E is the amplitude of the sampling voltage; e0Is a rated voltage amplitude; kQ/EIs a reactive voltage regulation coefficient; qsetIs a reactive set value; q is AC sampling reactive power; kQIs a reactive proportionality coefficient; evsgIs the virtual voltage amplitude.
The expression of the direct current active loop is as follows:
PDCref＝KDCP(UDCSET-UDC)
wherein, PDCrefThe value is a direct current active power regulating value; u shapeDCSampling voltage for a direct current pole; u shapeDCSETSetting a DC voltage; kDCPIs a direct current active coefficient.
Compared with the prior art, the invention has the beneficial effects that:
according to the invention, the control inner ring of the traditional control strategy is optimized, a new voltage and current double ring is added as an inner ring control mode, wherein the voltage ring adopts a special voltage dq decoupling control mode, and the control characteristic has the proportional characteristic of stable and quick response; the current loop adopts a dead beat control loop, and has the control characteristics of simple control and accurate current response. The voltage and current double-loop control inner ring formed by combining the two control modes has the advantages of quick and accurate voltage output and good electric energy quality.
The power control outer ring of the invention combines the traditional virtual synchronous machine control mode and the direct current voltage droop control ring. And an active power reference output obtained by the droop response of the direct-current voltage is fed forward to a d-axis of a voltage inner ring to improve the power response speed and is fed back to a VSG active ring to improve the control precision. Through the combination of the AC/DC power ring, the control mode obtains triple droop characteristics of active-DC voltage, active-AC frequency and reactive-AC amplitude, and the power support capability of the equipment for stabilizing the voltage at the two ends of AC/DC is realized.
The alternating current and direct current mutual aid control method is used in the hybrid power distribution network junction converter, and can effectively improve the voltage stability of the alternating current and direct current ends.
Drawings
FIG. 1 is a schematic diagram of an AC/DC power mutual aid control method;
FIG. 2 is an MMC equivalent circuit diagram;
fig. 3 is a dq decoupling voltage loop control block diagram.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. The embodiments described herein are only some embodiments of the invention, and not all embodiments. All other embodiments obtained by a person skilled in the art without making any inventive step on the basis of the spirit of the present invention are within the scope of protection of the present invention.
AC/DC mutual aid control mode:
the overall control mode of alternating current-direct current mutual-aid control is shown in fig. 1, and the control mode mainly comprises two parts, namely a power control outer ring and voltage-current double-ring inner ring control, wherein the power outer ring generates an alternating current voltage command by adopting a control mode based on a virtual synchronous machine, an active power command comprises a set power value, an alternating current frequency droop part and a direct current voltage droop part, the active ring generates a phase angle part of reference voltage, a reactive ring generates an amplitude part of the reference voltage, and the two parts jointly form three-phase reference voltage. The outer power loop exhibits a triple droop relationship in terms of external characteristics, active-dc voltage, active-ac frequency, and reactive-ac amplitude.
The reference voltage passes through the voltage and current double rings, so that the MMC outputs the voltage to quickly track the reference voltage, and the electric energy quality of the output current is improved. The voltage loop generates dq axis reference current in a dq decoupling control mode, three-phase current reference values are obtained through dq inverse transformation, the current loop enables the three-phase current to track the current reference values in real time in a dead beat control mode, and finally tracking of output voltage is achieved.
Voltage current double loop control mode:
FIG. 2 is an equivalent circuit diagram of the MMC. Wherein u issa、usb、uscIs the three-phase voltage of the system，L2Is a system equivalent reactance, L1Is an MMC equivalent reactance, the numerical value is half of the bridge arm reactance uoa、uob、uocOutputting three-phase voltage i for MMC equivalenceoa、iob、iocFor outputting three-phase currents u for MMCa、ub、ucFor MMC three-phase terminal voltage, UDCFor the DC terminal voltage of MMC, IDCCurrent flows into the MMC dc side. The positive directions of the above quantities are shown in the figure.
The relation between the MMC output voltage and the output current is discretized to obtain a relation formula shown in a formula (1):
wherein n is a discretized variable, uoa、uob、uocFor MMC equivalent output three-phase voltage ua、ub、ucFor the MMC three-phase terminal voltage, L1Is an MMC equivalent reactance, ioaOutputting three-phase current, T, for MMCsIs a control cycle.
And (3) replacing the current value at the next moment with the target reference output current reference value, and adding a dead beat coefficient to obtain a dead beat circuit loop shown in the formula (2).
Let the current loop kcThe coefficients are:
kc＝kdeadL1/Ts(0＜kdead＜1) (3)
wherein k iscIs the current loop coefficient, kdeadIs a dead beat coefficient.
The above results in the current loop portion of the voltage current double loop.
The output voltage u can be derived from fig. 2oa、uob、uocThe relationship between the dq-transformed data and the system parameters is as follows:
wherein u isd、uqIs the MMC terminal voltage u under dq coordinate systemsd、usqIs the system side voltage, i, in dq coordinate systemod、ioqIs an output current, L, in dq coordinate system2ω is the angular frequency of the sampled voltage for the system equivalent reactance.
A voltage loop dq decoupling control block diagram obtained by performing laplace transform on equation (4) is shown in fig. 3. Wherein f isc(s) is the current loop transfer function.
It can be seen from fig. 3 that the voltage loop has a feedforward coupling term, and the dq axes are required to have accurate fast response characteristics and to be subjected to dq decoupling control, and since the coupling phase is generated by feedforward, the setting of the decoupling term cannot be directly obtained as in the conventional current dq decoupling control, and needs to be calculated. Two phases of feed forward are respectively L2sAnd ωL2Considering the effect of obtaining the adjustment without difference and the stability of control, the final result of decoupling control should be a proportional link.
The target formula for decoupling is:
wherein f isc(s) is the current loop transfer function, s is the variable operator in the Lass transform, L2Omega is the angular frequency of the sampled voltage, u, for the system equivalent reactanced1、uq1For dq-axis voltage offset control quantity, upid、upiqAnd the pi output value is the deviation of the voltage of the dq axis MMC terminal from the target value voltage.
Combining fig. 3 and equation (5) with a typical voltage loop cutoff below 100rad/s, and ω is about the fundamental angular frequency 100 π rad/s, we can therefore deduce the feed forward decoupling parameters as:
since the differential term can amplify high frequency quantity in the control, for the stability and the disadvantage of the control, the differential term in the decoupling can be ignored in a mode of an equation (7) by combining the design size of the PI parameter, and the feedforward problem of the decoupling term is solved in a proportional mode.
The voltage-current loop control scheme shown in fig. 1 can be obtained by combining the formula (6), the formula (7) and fig. 3.
Power outer loop control mode:
the power outer ring adopts a control mode based on a virtual synchronous machine, and the control ring is shown as a control block diagram in the power outer ring in fig. 1.
In the alternating current active loop, omega is the angular frequency of the sampling voltage; omega0Is the rated angular frequency; kP/ωIs the active frequency modulation coefficient; psetIs an active power set value; pDCrefThe value is a direct current active power regulating value; prefIs the total reference power of the active loop; p is system sampling active power; d is a system virtual damping coefficient; js is a virtual moment of inertia; omegavsgIs the virtual angular frequency; deltavsgAnd outputting the phase angle for the virtual synchronous machine. The mathematical expression of the active ring of the virtual synchronous machine can be obtained from fig. 1:
in the alternating current reactive power loop, E is the amplitude of the sampling voltage; e0Is a rated voltage amplitude; kQ/EIs a reactive voltage regulation coefficient; qsetIs a reactive set value; q is AC sampling reactive power; kQIs a reactive proportionality coefficient; evsgIs the virtual voltage amplitude.
The mathematical expression of the reactive loop of the virtual synchronous machine can be obtained from fig. 1:
Evsg＝E0+kQ(kQ/E(E0-E)+Qset-Q) (9)
in the DC active ring, PDCrefThe value is a direct current active power regulating value; u shapeDCSampling voltage for a direct current pole; u shapeDCSETSetting a DC voltage; kDCPIs a direct current active coefficient.
The mathematical expression of the dc active loop can be obtained from fig. 1 as follows:
PDCref＝KDCP(UDCSET-UDC) (10)
from equation (8), the ac voltage frequency characteristic of the present control strategy is determined by the ac active outer loop active-frequency control characteristic, wherein there are three control parameters, i.e., J, D and KP/ω. J and D simulate the inertia characteristic which can be provided for a power grid by a synchronous generator, and the stability of alternating current frequency is improved; kP/ωThe AC active power-frequency coefficient is determined by equipment and power grid parameters, the primary frequency modulation characteristic of the synchronous generator is simulated, all the equipment in the power grid are mutually matched, automatic active power distribution is realized through the droop characteristic, and stable operation of multiple machines in parallel connection is realized. Control parameter K of direct current active loopDCPThe droop control of the direct-current voltage is realized, and meanwhile, the response speed of the direct-current voltage deviation is improved by directly introducing a mode of alternating-current output d-axis feedforward and alternating-current active outer ring feedback, so that the stability of the direct-current bus voltage can be effectively improved.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the embodiments of the invention without departing from the spirit and scope of the invention, which is to be covered by the claims.
Claims (9)
1. A device for controlling AC/DC mutual aid of a terminal converter of an AC/DC hybrid power distribution network comprises a power control outer ring and a voltage/current double ring, and is characterized in that,
the power control outer ring comprises a direct current voltage ring, an alternating current active ring and an alternating current reactive ring, the alternating current active ring and the alternating current reactive ring provide frequency response inertia characteristics for a power grid under the control of the virtual synchronous machine, the direct current voltage ring obtains a direct current power instruction through the droop of direct current voltage, and the direct current power instruction is fed forward to a voltage inner ring d shaft of the voltage ring and the alternating current active ring;
an alternating current active ring in the power control outer ring generates a phase angle part of reference voltage, an alternating current reactive ring generates an amplitude part of the reference voltage, and the phase angle part and the amplitude part jointly form three-phase reference voltage; the three-phase reference voltage passes through a voltage and current double ring, so that the output voltage of the AC-DC hybrid power distribution network junction converter tracks the reference voltage;
the voltage and current double rings comprise voltage rings and current rings, wherein the voltage rings generate dq-axis reference currents in a dq decoupling control mode, three-phase current reference values are obtained through dq inverse transformation, and the current rings enable the three-phase currents to track the current reference values in real time by adopting deadbeat control so as to realize tracking of output voltages.
2. The AC-DC mutual aid control method for the terminal converter of the AC-DC hybrid power distribution network according to claim 1,
the topological structure of the AC-DC hybrid power distribution network junction converter is MMC, and the relation between the output voltage and the output current of the MMC is discretized to obtain the following relation:
wherein n is a discretized variable, uoa、uob、uocFor MMC equivalent output three-phase voltage ua、ub、ucFor the MMC three-phase terminal voltage, L1Is an MMC equivalent reactance, ioaOutputting three-phase current, T, for MMCsIs a control cycle.
3. The AC-DC mutual aid control method for the AC-DC hybrid distribution network terminal converter according to claim 2,
the target reference output current reference value is used for replacing the current value at the next moment, and the dead beat coefficient is added to obtain the dead beat relational expression of the current loop as follows:
kc＝kdeadL1/Ts
wherein k iscIs the current loop coefficient, kdeadIs a dead beat coefficient.
4. The AC-DC mutual aid control method for the AC-DC hybrid distribution network terminal converter according to claim 3,
k isdeadThe value of (a) is in the range of 0 to 1.
5. The AC-DC mutual aid control method for the terminal converter of the AC-DC hybrid power distribution network according to claim 1,
AC-DC mutual aid control system side voltage usd、usqThe relationship after dq transformation is as follows:
wherein u isd、uqIs the MMC terminal voltage u under dq coordinate systemsd、usqIs the system side voltage, i, in dq coordinate systemod、ioqIs an output current, L, in dq coordinate system2ω is the angular frequency of the sampled voltage for the system equivalent reactance.
6. The AC-DC mutual aid control method for the terminal converter of the AC-DC hybrid power distribution network according to claim 1,
carrying out dq decoupling control on a feedforward coupling term existing in a voltage loop, wherein the decoupling target formula is as follows:
wherein f isc(s) is the current loop transfer function, s is the variable operator in the Lass transform, L2Omega is the angular frequency of the sampled voltage, u, for the system equivalent reactanced1、uq1For dq-axis voltage offset control quantity, upid、upiqAnd the pi output value is the deviation of the voltage of the dq axis MMC terminal from the target value voltage.
7. The AC-DC mutual aid control method for the terminal converter of the AC-DC hybrid power distribution network according to claim 1,
the virtual synchronous machine control comprises an active control loop, and the expression of the active control loop is as follows:
wherein, ω is the angular frequency of the sampled voltage; omega0Is the rated angular frequency; kP/ωIs the active frequency modulation coefficient; psetIs an active power set value; pDCrefThe value is a direct current active power regulating value; prefIs the total reference power of the active loop; p is system sampling active power; d is a system virtual damping coefficient; js is a virtual moment of inertia; omegavsgIs the virtual angular frequency.
8. The AC-DC mutual aid control method for the terminal converter of the AC-DC hybrid power distribution network according to claim 1,
the virtual synchronous machine control comprises a reactive power control loop, and the expression of the reactive power control loop is as follows:
Evsg＝E0+kQ(kQ/E(E0-E)+Qset-Q)
wherein E is the amplitude of the sampling voltage; e0Is a rated voltage amplitude; kQ/EIs a reactive voltage regulation coefficient; qsetIs a reactive set value; q is AC sampling reactive power; kQIs a reactive proportionality coefficient; evsgIs the virtual voltage amplitude.
9. The AC-DC mutual aid control method for the terminal converter of the AC-DC hybrid power distribution network according to claim 1,
the expression of the direct current active loop is as follows:
PDCref＝KDCP(UDCSET-UDC)
wherein, PDCrefThe value is a direct current active power regulating value; u shapeDCSampling voltage for a direct current pole; u shapeDCSETSetting a DC voltage; kDCPIs a direct current active coefficient.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113394801A (en) * | 2021-06-01 | 2021-09-14 | 广西电网有限责任公司南宁供电局 | Power control method of lead-acid storage battery energy storage system |
| CN115378043A (en) * | 2022-08-09 | 2022-11-22 | 中车株洲电力机车研究所有限公司 | Synchronous power generation system, grid-connected control method and device thereof, and electronic equipment |
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| CN115378043B (en) * | 2022-08-09 | 2023-08-25 | 中车株洲电力机车研究所有限公司 | Synchronous power generation system, grid-connected control method and device thereof and electronic equipment |
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