CN-122026541-A - Simulation circuit and capacity check method for full working condition of network-structured energy storage adaptive micro-grid

CN122026541ACN 122026541 ACN122026541 ACN 122026541ACN-122026541-A

Abstract

The invention relates to the technical field of power system simulation and operation control, in particular to a simulation circuit and a capacity checking method of a grid-structured energy storage adaptive micro-grid, which comprise a data processing unit, a grid framework model and a grid-structured energy storage module, the power grid framework model comprises an I section bus, an II section bus, a transformer and a power transmission line, and also comprises a load unit model and a power supply model, wherein the energy storage unit model, the load unit model and the power supply model are connected with the I section bus and the II section bus in a high-voltage direct hanging mode. The invention aims at the design of the network-structured energy storage module, defines the capacity allocation and control strategy and the adaptation logic of the existing micro-grid assembly, solves the problem of insufficient attention of the existing simulation circuit to the energy storage module, and determines the lowest energy storage capacity by combining the existing load characteristics of the micro-grid through the standardized checking flow of the split bus and the split working condition, thereby avoiding the surplus or insufficient capacity allocation and improving the engineering economy and reliability.

Inventors

LI HONGDE
YE XIJUN
SU CHUNYANG
Mei Haihua
JI CHENYANG
CHEN NAN
YANG LUKAI

Assignees

新力时代能源科技有限公司
靖江特殊钢有限公司

Dates

Publication Date: 20260512
Application Date: 20251231

Claims (10)

1. Full operating mode's of net formula energy storage adaptation little electric wire netting analog circuit, its characterized in that includes: the power grid framework model (100) comprises an I-section bus (101) and a II-section bus (102) which are connected through a bus bar, and a power transmission line which is respectively connected with the I-section bus (101) and the II-section bus (102) through a transformer (103); the grid-structured energy storage module (200) is respectively connected to the I section bus (101) and the II section bus (102) in a high-voltage direct-hanging mode and is used for providing voltage and frequency support for the power grid framework model (100); the loads in the range of the section I bus (101) and the section II bus (102) are unequal.
2. The network-structured energy storage adaptive micro-grid full-condition simulation circuit according to claim 1, wherein the network-structured energy storage module (200) comprises a plurality of groups of energy storage units (201), and the section I bus (101) and the section II bus (102) are configured with at least one group of energy storage units (201).
3. The network-structured energy storage adaptive micro-grid all-condition simulation circuit according to claim 2, wherein the energy storage unit (201) is internally integrated with a control module, and the control module comprises: The frequency adjusting unit (201 a) is positioned at the top layer of the control module, and the frequency adjusting unit (201 a) realizes frequency quick response through virtual inertia simulation and maintains the system frequency within a preset stability range; the voltage supporting unit (201 b) is parallel to the frequency adjusting unit (201 a), and the voltage supporting unit (201 b) is used for detecting the bus voltage in real time and dynamically outputting reactive power to maintain the bus voltage within a preset stability range; The overcurrent protection unit (201 c) is used as a bottom protection module and is connected in series with an output loop of the energy storage unit (201), the overcurrent protection unit (201 c) is provided with a short-time overcurrent threshold, and when the output current of the energy storage unit (201) exceeds the threshold, the current limiting control is automatically started.
4. The network-structured energy storage adaptive micro-grid all-condition simulation circuit according to claim 1 or 3, further comprising a load unit model (300) and a power supply model (400); The load unit model (300) and the power supply model (400) are connected into the I-section bus (101) and the II-section bus (102) through grid-connected access points.
5. The network-structured energy storage adaptive micro-grid full-condition simulation circuit according to claim 4, wherein the load unit model (300) comprises an impact load model (301) and a sensitive load model (302) which are respectively arranged in the range of the section I bus (101) and the section II bus (102); the impact load model (301) is used for simulating constant current and constant power composite characteristics; The sensitive load model (302) is used to simulate motor and inverter load characteristics.
6. The network-structured energy storage adaptive micro-grid full-condition simulation circuit according to claim 1, 3 or 5, wherein the power model (400) comprises: The wind power generation model (401) comprises a newly built wind power generation model (401 a) which is connected in the range of the I section bus (101), and an established wind power generation model (401 b) which is connected in the range of the II section bus (102), wherein the wind power generation model (401) adopts an induction generator model and is configured with phase-locked loop constant power control; The photovoltaic power generation model (402) comprises a newly built photovoltaic sub-model (402 a) which is connected in the range of the I-section bus (101), a built photovoltaic sub-model (402 b) which is connected in the range of the II-section bus (102), and the photovoltaic power generation model (402) adopts an MPPT control mode to reasonably distribute reactive power through voltage outer ring and current inner ring closed-loop control.
7. The capacity checking method for the full working condition of the grid-structured energy storage adaptive micro-grid is characterized by comprising the following steps of: s1, defining a plurality of basic operation modes, wherein the basic operation modes comprise a grid-connected mode and a grid-disconnected mode, and the different modes comprise two working conditions of large new energy sources and small new energy sources; S2, setting a set of standardized disturbance test sets aiming at each basic operation mode; S3, sequentially applying the disturbance test set to a simulation circuit of the full working condition of the grid-built energy storage adaptive micro-grid to perform dynamic simulation; And S4, analyzing simulation result data, checking capacity rationality based on a preset stability criterion, and determining the lowest energy storage capacity by a sub-bus.
8. The method for checking capacity under all conditions of a grid-structured energy storage adaptive micro-grid according to claim 7, wherein the standardized disturbance test set in the step S4 includes at least three of the following disturbance types: the source side power disturbance is used for simulating the illumination intensity or the step change of the wind speed; The load side power disturbance is used for simulating sudden input or exit of a high-capacity impact load; the short circuit fault is used for simulating transient or permanent short circuit faults occurring at different positions in the power grid; And the off-grid switching disturbance is used for simulating a dynamic process that the micro-grid is forced to be switched into off-grid operation due to serious faults on the main grid side.
9. The method for checking the capacity of the network-structured energy storage adaptive micro-grid under all conditions as set forth in claim 7, wherein the stability criteria in step S4 include: the bus voltage is maintained within a range of 0.9-1.1 per unit; the system frequency is maintained within the range of 49.5 Hz-50.5 Hz; the output current of the energy storage unit does not exceed 1.5 times of short-time overcurrent threshold.
10. The method for checking the capacity of the network-structured energy storage adaptive micro-grid under all working conditions as set forth in claim 7, wherein the method further comprises the step of S5: generating a networking type energy storage overcurrent capacity selection proposal and/or a stable control load shedding strategy proposal based on the checking result of the step S4.

Description

Simulation circuit and capacity check method for full working condition of network-structured energy storage adaptive micro-grid Technical Field The invention relates to the technical field of power system simulation and operation control, in particular to a simulation circuit and a capacity checking method of a grid-structured energy storage adaptive micro-grid. Background The micro-grid is used as a small power generation and distribution system integrating distributed new energy, load and energy storage, and needs to stably operate in a grid-connected mode and an off-grid mode, and the core challenge is the system stability problem caused by random fluctuation of new energy output and sudden change of impact load power. The network-structured energy storage can provide voltage and frequency support by virtue of a Virtual Synchronous Generator (VSG) control technology, and becomes a key device for solving the stability problem of the micro-grid. In the prior art, micro-grid simulation focuses on the verification of the working condition of the whole system, a special simulation framework is not designed aiming at the core characteristics of the grid-structured energy storage, so that the parameter suitability and the capacity rationality of an energy storage module cannot be accurately verified, and meanwhile, a capacity checking method lacks a standardized flow, is difficult to match with the differentiated requirements of different bus load characteristics (impact load and sensitive load), and is easy to cause the problem of surplus or insufficient energy storage capacity configuration. In addition, the existing simulation circuit does not highlight the cooperative adaptation relation between the grid-structured energy storage and the existing power supply and load module of the micro-grid, and the improvement effect of the energy storage module on the system stability cannot be accurately reflected. Disclosure of Invention Some simplifications or omissions may be made in this section as well as in the description of the application and in the title of the application, which may not be used to limit the scope of the application. In order to solve the defects in the prior art, the invention aims to provide a simulation circuit for constructing a net type energy storage adaptive micro-grid full-working condition, which is used for determining core design parameters of an energy storage module and adaptive logic of the existing system, determining optimal capacity configuration through a standardized checking flow and ensuring that the net type energy storage plays an optimal stable supporting role under the micro-grid full-working condition. In order to achieve the purpose, the invention adopts the following technical scheme that the simulation circuit for constructing the full working condition of the energy storage adaptive micro-grid comprises: The power grid framework model comprises an I section bus and a II section bus which are connected through a bus connection, and a power transmission line which is respectively connected with the I section bus and the II section bus through a transformer, wherein the power grid framework model is stored in a data processing unit, and the data processing unit is used for executing simulation calculation and disturbance injector data acquisition analysis; the grid-structured energy storage module is respectively connected with the I section bus and the II section bus in a high-voltage direct hanging mode and is used for providing voltage and frequency support for the power grid framework model; And the loads in the range of the section I bus and the section II bus are unequal. As an optimal scheme of the network-structured energy storage adaptive micro-grid full-working-condition simulation circuit, the network-structured energy storage module comprises a plurality of groups of energy storage units, and at least one group of energy storage units is configured by the I-section bus and the II-section bus. As an optimal scheme of the network-structured energy storage adaptive micro-grid full-working-condition simulation circuit, the invention comprises an energy storage unit internal integrated control module, wherein the control module comprises: The frequency adjusting unit is positioned at the top layer of the control module, realizes frequency quick response through virtual inertia simulation, and maintains the system frequency within the range of 49.5 Hz-50.5 Hz; The voltage support unit is used for detecting bus voltage in real time, dynamically outputting reactive power through the U-Q sagging characteristic and maintaining the bus voltage within a 0.9-1.1 per unit value range; The overcurrent protection unit is used as a bottom protection module and is connected in series with an output loop of the energy storage unit, the overcurrent protection unit is provided with a short-time overcurrent threshold (10 s tolerance time) which is 1.5 times, and when the out