阅读说明：本技术 一种电能转换系统 (Electric energy conversion system ) 是由 魏西平 刘天武 郑艳文 周祖平 魏民 于 2019-10-12 设计创作，主要内容包括：本申请公开了一种电能转换系统,所述电能转换系统通过飞轮储能作为能量媒介,在冲击性负荷发生时(即所述目标电网接入的负荷超过预设阈值时),利用飞轮转盘存储的电能为目标电网供电。在冲击性负荷停止后(即在所述目标电网接入的负荷小于预设阈值时),利用目标电网给飞轮转盘储能充电,由此使得微电网间接地给冲击性负荷供给能量,冲击性负荷与微电网完全隔离没有电气连接,从而实现了保证微电网在冲击性负荷的情况下依然可以可靠供电,同时又可避免冲击性负荷对于微电网的冲击的目的,解决了冲击性负荷导致的微电网谐波污染严重、电压波动和闪变、三相不平衡以及系统频率震荡的问题。(The application discloses electric energy conversion system, electric energy conversion system passes through the flywheel energy storage as energy medium, when the impact load takes place (promptly when the load that the target electric wire netting inserts exceeds and predetermines the threshold value), utilizes the electric energy of flywheel carousel storage to supply power for the target electric wire netting. After the impact load stops (namely when the load accessed by the target power grid is smaller than a preset threshold value), the target power grid is utilized to store energy and charge the flywheel turntable, so that the micro power grid indirectly supplies energy to the impact load, and the impact load is completely isolated from the micro power grid without electrical connection, thereby realizing the purpose of ensuring that the micro power grid can still reliably supply power under the condition of the impact load, avoiding the impact of the impact load on the micro power grid, and solving the problems of serious harmonic pollution, voltage fluctuation and flicker, three-phase imbalance and system frequency oscillation of the micro power grid caused by the impact load.)

1. an electrical energy conversion system, comprising: the device comprises a power grid access device, a current transformation device, a flywheel motor and a flywheel turntable; wherein the content of the first and second substances,

One end of the power grid access device is used for connecting a target power grid, and the other end of the power grid access device is used for connecting a converter device;

One end of the converter device, which is far away from the power grid access device, is connected with the flywheel motor;

One end of the flywheel motor, which is far away from the converter device, is connected with the flywheel turntable;

The flywheel motor is used for dragging the flywheel turntable to reduce the speed when the load connected to the target power grid exceeds a preset threshold value, so that the flywheel turntable works in a power generation mode, and the converter device supplies power to the target power grid by using the electric energy stored in the flywheel turntable; and the flywheel turntable is driven to accelerate by the electric energy of the target power grid converted by the converter device when the load accessed by the target power grid is smaller than a preset threshold value, so that the electric energy of the target power grid is stored in the flywheel turntable.

2. an electric energy conversion system according to claim 1, characterized in that the flow altering devices comprise: a first converter and a second converter; wherein the content of the first and second substances,

one end of the first converter is connected with one end of the power grid access device, and the other end of the first converter is connected with the second converter;

One end of the second converter, which is far away from the first converter, is connected with the flywheel electrode;

the second converter is used for converting the three-phase alternating-current electric energy stored in the flywheel turntable into direct-current electric energy when the load connected to the target power grid exceeds a preset threshold value, so that the first converter converts the direct-current electric energy into the three-phase alternating-current electric energy and supplies power to the target power grid;

the first converter is used for converting the three-phase alternating-current electric energy provided by the target power grid into the direct-current electric energy when the load connected to the target power grid is smaller than a preset threshold value, so that the second converter converts the direct-current electric energy into the three-phase alternating-current electric energy to drive the flywheel motor, and the flywheel motor drives the flywheel turntable to increase the speed, so that the electric energy of the target power grid is stored in the flywheel turntable.

3. The electrical energy conversion system of claim 2 wherein the first and second current transformers are each a three-phase full bridge configuration.

4. the electrical energy conversion system of claim 3, wherein the three-phase full bridge configuration comprises:

the converter comprises a first converter unit, a second converter unit and a third converter unit which are connected in parallel.

5. The electric energy conversion system of claim 4, wherein the first converter unit, the second converter unit and the third converter unit are each formed by two converter devices connected in series;

the current transformer comprises: a first transistor and a first diode;

the emitter of the first transistor is connected with the anode of the first diode, and the collector of the first transistor is connected with the cathode of the first diode.

6. An electric energy conversion system according to claim 2, characterized in that the flow altering devices further comprise:

and the first capacitor is connected between the first current transformer and the second current transformer.

7. an electric energy conversion system according to claim 1, characterized in that the grid access device comprises three reactors.

8. The electrical energy conversion system of claim 1, wherein the flywheel motor is an asynchronous motor.

9. The electrical energy conversion system of claim 8, wherein the flywheel motor is coaxially coupled to the flywheel rotor.

Technical Field

the application relates to the technical field of power grids, in particular to an electric energy conversion system.

Background

a Micro-Grid (Micro-Grid), also called a microgrid, refers to a small power generation and distribution system composed of a distributed power supply, an energy storage device, an energy conversion device, a load, a monitoring and protection device, and the like.

The load of little electric wire netting is mostly impact load, when the load is great, can lead to the little electric wire netting to appear the quality poor and harmonic headlight problem. The micro-grid is used as a small grid, the power generation and the load of the micro-grid have large fluctuation and uncertainty, and particularly in the military field, the load fluctuation can not be effectively predicted. The impact load has many hazards to the power grid due to the short time and large amplitude. The impact load can cause the following accidents to occur on the power grid: serious harmonic pollution, voltage fluctuation and flicker, three-phase unbalance and system frequency oscillation.

In the prior art, in order to control an impact load, a majority of documents deal with filtering and using an SVC (Static Var Compensator) device. However, the micro-grid has small self inertia coefficient and insufficient damping, and does not have the anti-disturbance capacity of a large grid, so that an electric energy conversion system is more needed to adjust under the impact load.

Disclosure of Invention

In order to solve the technical problem, the application provides an electric energy conversion system to guarantee that the micro-grid still can reliably supply power under the condition of impact load, can avoid the impact of impact load to the micro-grid simultaneously, solve the problem that the micro-grid harmonic that impact load leads to pollutes seriously, voltage fluctuation and flicker, unbalanced three-phase and system frequency vibrates.

In order to achieve the technical purpose, the embodiment of the application provides the following technical scheme:

An electrical energy conversion system comprising: the device comprises a power grid access device, a current transformation device, a flywheel motor and a flywheel turntable; wherein the content of the first and second substances,

One end of the power grid access device is used for connecting a target power grid, and the other end of the power grid access device is used for connecting a converter device;

One end of the converter device, which is far away from the power grid access device, is connected with the flywheel motor;

one end of the flywheel motor, which is far away from the converter device, is connected with the flywheel turntable;

The flywheel motor is used for dragging the flywheel turntable to reduce the speed when the load connected to the target power grid exceeds a preset threshold value, so that the flywheel turntable works in a power generation mode, and the converter device supplies power to the target power grid by using the electric energy stored in the flywheel turntable; and the flywheel turntable is driven to accelerate by the electric energy of the target power grid converted by the converter device when the load accessed by the target power grid is smaller than a preset threshold value, so that the electric energy of the target power grid is stored in the flywheel turntable.

optionally, the deflector includes: a first converter and a second converter; wherein the content of the first and second substances,

One end of the first converter is connected with one end of the power grid access device, and the other end of the first converter is connected with the second converter;

one end of the second converter, which is far away from the first converter, is connected with the flywheel electrode;

The second converter is used for converting the three-phase alternating-current electric energy stored in the flywheel turntable into direct-current electric energy when the load connected to the target power grid exceeds a preset threshold value, so that the first converter converts the direct-current electric energy into the three-phase alternating-current electric energy and supplies power to the target power grid;

the first converter is used for converting the three-phase alternating-current electric energy provided by the target power grid into the direct-current electric energy when the load connected to the target power grid is smaller than a preset threshold value, so that the second converter converts the direct-current electric energy into the three-phase alternating-current electric energy to drive the flywheel motor, and the flywheel motor drives the flywheel turntable to increase the speed, so that the electric energy of the target power grid is stored in the flywheel turntable.

Optionally, the first converter and the second converter are both in a three-phase full-bridge structure.

Optionally, the three-phase full-bridge structure includes:

The converter comprises a first converter unit, a second converter unit and a third converter unit which are connected in parallel.

Optionally, the first converter unit, the second converter unit and the third converter unit are all formed by two converter devices connected in series;

The current transformer comprises: a first transistor and a first diode;

the emitter of the first transistor is connected with the anode of the first diode, and the collector of the first transistor is connected with the cathode of the first diode.

optionally, the variable flow device further includes:

And the first capacitor is connected between the first current transformer and the second current transformer.

Optionally, the grid access device includes three reactors.

optionally, the flywheel motor is an asynchronous motor.

optionally, the flywheel motor is coaxially connected with the flywheel turntable.

according to the technical scheme, the electric energy conversion system uses flywheel energy storage as an energy medium, and when an impact load occurs (namely the load connected to the target power grid exceeds a preset threshold), the electric energy stored by the flywheel turntable is used for supplying power to the target power grid. After the impact load stops (namely when the load accessed by the target power grid is smaller than a preset threshold value), the target power grid is utilized to store energy and charge the flywheel turntable, so that the micro power grid indirectly supplies energy to the impact load, and the impact load is completely isolated from the micro power grid without electrical connection, thereby realizing the purpose of ensuring that the micro power grid can still reliably supply power under the condition of the impact load, avoiding the impact of the impact load on the micro power grid, and solving the problems of serious harmonic pollution, voltage fluctuation and flicker, three-phase imbalance and system frequency oscillation of the micro power grid caused by the impact load.

drawings

in order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, it is obvious that the drawings in the following description are only embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

Fig. 1 is a schematic structural diagram of an electric energy conversion system according to an embodiment of the present application;

fig. 2 is a schematic structural diagram of an electric energy conversion system according to another embodiment of the present application;

fig. 3 is a schematic structural diagram of an electric energy conversion system according to another embodiment of the present application;

FIG. 4 is a schematic diagram of an electrical energy conversion system according to an alternative embodiment of the present application;

FIG. 5 is a schematic diagram of an electrical energy conversion system according to another alternative embodiment of the present application;

fig. 6 is a schematic structural diagram of an electric energy conversion system according to yet another alternative embodiment of the present application.

Detailed Description

as mentioned in the background, most of the prior art literature deals with filtering and using SVC (Static Var Compensator) devices. However, the micro-grid has small self inertia coefficient and insufficient damping, and does not have the anti-disturbance capacity of a large grid, so that an electric energy conversion system is more needed to adjust under the impact load.

In view of this, an embodiment of the present application provides an electric energy conversion system, including: the device comprises a power grid access device, a current transformation device, a flywheel motor and a flywheel turntable; wherein the content of the first and second substances,

One end of the power grid access device is used for connecting a target power grid, and the other end of the power grid access device is used for connecting a converter device;

One end of the converter device, which is far away from the power grid access device, is connected with the flywheel motor;

one end of the flywheel motor, which is far away from the converter device, is connected with the flywheel turntable;

the flywheel motor is used for dragging the flywheel turntable to reduce the speed when the load connected to the target power grid exceeds a preset threshold value, so that the flywheel turntable works in a power generation mode, and the converter device supplies power to the target power grid by using the electric energy stored in the flywheel turntable; and the flywheel turntable is driven to accelerate by the electric energy of the target power grid converted by the converter device when the load accessed by the target power grid is smaller than a preset threshold value, so that the electric energy of the target power grid is stored in the flywheel turntable.

The electric energy conversion system takes flywheel energy storage as an energy medium, and when an impact load occurs (namely the load connected to the target power grid exceeds a preset threshold), the electric energy stored by the flywheel turntable is used for supplying power to the target power grid. After the impact load stops (namely when the load accessed by the target power grid is smaller than a preset threshold value), the target power grid is utilized to store energy and charge the flywheel turntable, so that the micro power grid indirectly supplies energy to the impact load, and the impact load is completely isolated from the micro power grid without electrical connection, thereby realizing the purpose of ensuring that the micro power grid can still reliably supply power under the condition of the impact load, avoiding the impact of the impact load on the micro power grid, and solving the problems of serious harmonic pollution, voltage fluctuation and flicker, three-phase imbalance and system frequency oscillation of the micro power grid caused by the impact load.

the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Reference throughout this specification to "one embodiment" or similar language means that a feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases "in one embodiment," "in an embodiment," and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

furthermore, the described features, structures, or characteristics of the invention may be combined in any suitable manner in one or more embodiments. One skilled in the relevant art will recognize, however, that the invention may be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown in detail to avoid obscuring the invention.

An embodiment of the present application provides an electric energy conversion system, as shown in fig. 1, including: the system comprises a power grid access device 10, a converter device 20, a flywheel motor 30 and a flywheel turntable 40; wherein the content of the first and second substances,

one end of the power grid access device 10 is used for connecting a target power grid, and the other end of the power grid access device is used for connecting a converter device 20;

one end of the converter device 20 far away from the power grid access device 10 is connected with a flywheel motor 30;

one end of the flywheel motor 30, which is far away from the deflector 20, is connected with the flywheel turntable 40;

the flywheel motor 30 is configured to, when a load connected to the target power grid exceeds a preset threshold, drag the flywheel turntable 40 to reduce the speed, so that the flywheel turntable 40 operates in a power generation mode, and the converter device 20 supplies power to the target power grid by using the electric energy stored in the flywheel turntable 40; and the flywheel turntable 40 is dragged to increase the speed under the driving of the electric energy of the target power grid converted by the converter device 20 when the load connected to the target power grid is smaller than a preset threshold value, so as to store the electric energy of the target power grid in the flywheel turntable 40.

In this embodiment, the electric energy conversion system uses flywheel energy storage as an energy medium, and when an impact load occurs (that is, when a load connected to the target power grid exceeds a preset threshold), the electric energy stored in the flywheel turntable 40 is used to supply power to the target power grid. After the impact load stops (namely when the load accessed by the target power grid is smaller than a preset threshold value), the target power grid is used for storing and charging energy for the flywheel turntable 40, so that the micro power grid indirectly supplies energy for the impact load, and the impact load is completely isolated from the micro power grid without electrical connection, so that the micro power grid can still reliably supply power under the condition of the impact load, meanwhile, the impact of the impact load on the micro power grid can be avoided, and the problems of serious harmonic pollution, voltage fluctuation and flicker, three-phase imbalance and system frequency oscillation of the micro power grid caused by the impact load are solved.

as described below for each component of the electric energy conversion system, optionally, as shown in fig. 2, the converter device 20 includes: a first converter 21 and a second converter 22; wherein the content of the first and second substances,

One end of the first converter 21 is connected with one end of the grid access device 10, and the other end is connected with the second converter 22;

one end of the second converter 22 far away from the first converter 21 is connected with the flywheel electrode;

The second converter 22 is configured to convert the electric energy in the three-phase alternating current form stored in the flywheel turntable 40 into the electric energy in the direct current form when the load connected to the target power grid exceeds a preset threshold, so that the first converter 21 converts the electric energy in the direct current form into the electric energy in the three-phase alternating current form and supplies power to the target power grid;

the first converter 21 is configured to, when a load connected to the target power grid is smaller than a preset threshold, convert the three-phase ac power provided by the target power grid into a dc power, so that the second converter 22 converts the dc power into the three-phase ac power to drive the flywheel motor 30, and the flywheel motor 30 drives the flywheel turntable 40 to increase the speed, so as to store the electric power of the target power grid in the flywheel turntable 40.

Referring to fig. 3, the first current transformer 21 and the second current transformer 22 are both a three-phase full-bridge structure.

the three-phase full-bridge structure includes:

The converter comprises a first converter unit, a second converter unit and a third converter unit which are connected in parallel.

The first converter unit, the second converter unit and the third converter unit are all formed by two converter devices connected in series;

the current transformer comprises: a first transistor Q1 and a first diode D1;

The emitter of the first transistor Q1 is connected to the anode of the first diode D1, and the collector of the first transistor Q1 is connected to the cathode of the first diode D1.

On the basis of the above embodiment, in an embodiment of the present application, as shown in fig. 4, the deflector 20 further includes:

and a first capacitor C connected between the first current transformer 21 and the second current transformer 22.

The first capacitor C is used for filtering stray electric energy signals.

alternatively, referring to fig. 5, the grid access device 10 includes three reactors L.

Each of the reactors L is configured to provide a phase power path.

Optionally, the flywheel motor 30 is an asynchronous motor.

Optionally, the flywheel motor 30 is coaxially connected to the flywheel turntable 40.

Referring to fig. 6, fig. 6 is a schematic diagram of an application scenario of the electric energy conversion system, where after the target power grid is connected to the electromagnetic gun, the electromagnetic gun is an impact load with a short time and a large amplitude.

when the electromagnetic gun is not started, the target power grid converts the three-phase alternating-current electric energy of the target power grid into the direct-current electric energy through the reactor L and the first converter 21, the second converter 22 converts the direct-current electric energy into the three-phase alternating-current electric energy to drive the flywheel motor 30 to increase the speed, the flywheel motor 30 drives the flywheel turntable 40 to increase the speed, and the electric energy is stored in the flywheel turntable 40 in the form of kinetic energy.

when the electromagnetic gun is started, the second converter 22 outputs electric energy in a three-phase alternating current form to drag the flywheel motor 30 to decelerate, the flywheel motor 30 drags the flywheel turntable 40 to decelerate, the flywheel motor 30 works in a power generation state, the electric energy stored in the flywheel turntable 40 in a kinetic energy form is converted into electric energy in a three-phase alternating current form, the second converter 22 converts the electric energy in the three-phase alternating current form into electric energy in a direct current form, the first converter 21 converts the electric energy in the direct current form into the electric energy in the three-phase alternating current form, the electric energy is fed back to a target power grid through the reactor L, and power is supplied.

correspondingly, the embodiment of the application also provides a microgrid which comprises a load and the electric energy conversion system as described in any one of the above embodiments.

referring to fig. 1, the electric energy conversion system includes: the system comprises a power grid access device 10, a converter device 20, a flywheel motor 30 and a flywheel turntable 40; wherein the content of the first and second substances,

One end of the power grid access device 10 is used for connecting a target power grid, and the other end of the power grid access device is used for connecting a converter device 20;

One end of the converter device 20 far away from the power grid access device 10 is connected with a flywheel motor 30;

One end of the flywheel motor 30, which is far away from the deflector 20, is connected with the flywheel turntable 40;

The flywheel motor 30 is configured to, when a load connected to the target power grid exceeds a preset threshold, drag the flywheel turntable 40 to reduce the speed, so that the flywheel turntable 40 operates in a power generation mode, and the converter device 20 supplies power to the target power grid by using the electric energy stored in the flywheel turntable 40; and the flywheel turntable 40 is dragged to increase the speed under the driving of the electric energy of the target power grid converted by the converter device 20 when the load connected to the target power grid is smaller than a preset threshold value, so as to store the electric energy of the target power grid in the flywheel turntable 40.

Optionally, referring to fig. 6, the load may be an electromagnetic gun 50, and after the microgrid is connected to the electromagnetic gun 50, the electromagnetic gun 50 is an impact load with a short time and a large amplitude.

When the electromagnetic gun 50 is not started, the microgrid converts the three-phase alternating-current electric energy of the microgrid into the direct-current electric energy through the reactor L and the first converter 21, the second converter 22 converts the direct-current electric energy into the three-phase alternating-current electric energy to drive the flywheel motor 30 to increase the speed, the flywheel motor 30 drives the flywheel turntable 40 to increase the speed, and the electric energy is stored in the flywheel turntable 40 in the form of kinetic energy.

When the electromagnetic gun 50 is started, the second converter 22 outputs electric energy in a three-phase alternating current form to drag the flywheel motor 30 to decelerate, the flywheel motor 30 drags the flywheel turntable 40 to decelerate, so that the flywheel motor 30 works in a power generation state, the electric energy stored in the flywheel turntable 40 in a kinetic energy form is converted into the electric energy in the three-phase alternating current form, the second converter 22 converts the electric energy in the three-phase alternating current form into the electric energy in a direct current form, the first converter 21 converts the electric energy in the direct current form into the electric energy in the three-phase alternating current form, the electric energy is fed back to the micro-grid through the reactor L, and.

To sum up, the embodiment of the present application provides an electric energy conversion system, the electric energy conversion system uses flywheel energy storage as an energy medium, and when an impact load occurs (that is, when a load accessed by a target power grid exceeds a preset threshold), the electric energy stored by the flywheel turntable 40 is used for supplying power to the target power grid. After the impact load stops (namely when the load accessed by the target power grid is smaller than a preset threshold value), the target power grid is used for storing and charging energy for the flywheel turntable 40, so that the micro power grid indirectly supplies energy for the impact load, and the impact load is completely isolated from the micro power grid without electrical connection, so that the micro power grid can still reliably supply power under the condition of the impact load, meanwhile, the impact of the impact load on the micro power grid can be avoided, and the problems of serious harmonic pollution, voltage fluctuation and flicker, three-phase imbalance and system frequency oscillation of the micro power grid caused by the impact load are solved.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

the previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.