CN116316774A - Modular converter and control method for flexible interconnection device in station area - Google Patents

Abstract

The invention provides a modularized converter and a control method for a flexible interconnection device of a platform area, wherein the modularized converter comprises a flexible interconnection controller of the platform area and also comprises a modularized converter formed by a power module controller and at least one power module; the flexible interconnection controller of the platform area is used for controlling the power, voltage and operation mode switching of all the modularized converters in the flexible interconnection device of the platform area; the power module controller generates a synchronous control signal to realize the regulation of the output characteristics of the modularized converter or control the running number of the power modules; the flexible interconnection controller of the station area is connected with the power module controller through a communication link, and the communication mode of the communication link comprises a CAN bus, a network cable and a control cable; the power module controller is communicated with the power module through a CAN bus; the invention can reduce the manufacturing cost, the operation efficiency and the reliability of the transformer of the flexible interconnection device of the transformer area.

Description

Modular converter and control method for flexible interconnection device in station area

technical field

The invention relates to the technical field of low-voltage intelligent power distribution, in particular to a modular converter and a control method for a flexible interconnection device in a station area.

Background technique

Under the background of the national "dual carbon" strategy, distributed photovoltaics and charging piles are connected to the grid on a large scale, which puts forward higher requirements on the power supply capacity and power quality of the Taiwan area.

The flexible interconnection of the station area can realize power mutual aid between stations with different load characteristics, fault transfer, power management, etc., and can effectively improve the power supply capacity and power quality of the station area.

At present, the flexible interconnection devices in the station area have the following problems:

(1) The flexible interconnection device of the station area generally adopts the scheme of AC-DC-AC. Since the capacity of the interconnection station area is different, the flexible interconnection device needs to be customized, and the manufacturing cost is relatively high at this stage.

(2) Since the load in the station area is significantly affected by users and the load fluctuates greatly, the utilization rate of the flexible interconnection device may be insufficient, which will lead to a decrease in operating efficiency.

The present invention proposes a solution to the above problems.

Contents of the invention

The invention proposes a modularized converter and a control method for flexible interconnection devices in the station area, which can reduce the manufacturing cost, operating efficiency and reliability of the converter in the flexible interconnection device in the station area.

The present invention adopts the following technical solutions.

A control method for a modular converter used for a flexible interconnection device in a station area, the control method includes a flexible interconnection controller in a station area, and a module composed of a power module controller and no less than one power module The flexible interconnection controller in the station area is used to switch the power, voltage and operation mode of all modularized converters in the flexible interconnection device in the console area; the power module controller generates synchronous control signals to realize modularization conversion Adjust the output characteristics of the device or control the number of running power modules; the flexible interconnection controller of the platform and the power module controller are connected by a communication link, and the communication link communication mode includes CAN bus, network cable, and control cable; the said The power module controller communicates with the power module through the CAN bus.

The working mode of the power module includes an independent working mode and a cooperative control mode; when the power module works in the cooperative control mode, the power module controller generates a synchronous control signal, and controls the power module through the CAN bus to realize multiple The power modules work together.

The power module controller generates a synchronous control signal and a control mode switching command according to the control command of the station area flexible interconnection controller. The control modes include constant voltage and constant frequency control mode, constant power control mode, and constant DC voltage control mode.

The power module controller adjusts the number of power modules put into operation according to the output power of the current modular converter, and reduces power conversion loss by sharing the total output power of the converter equally among the power modules.

The total rated power of the power modules put into operation is greater than 1.2 times the output power of the modular converter.

When the working state of the power module is abnormal, the power module controller disconnects the power module with abnormal working state, and sends the information of the power module with abnormal working state to the flexible interconnection controller in the station area.

The modularized converter used for the flexible interconnection device of the platform area, the modularized converter includes a power module controller, and also includes a modularized converter composed of a plurality of power modules, the circuit topology of the power module Including two-level converter circuit topology, midpoint clamped three-level converter circuit topology, multiple power modules connected in parallel to form a modular converter, the total power of the parallel connected power modules is not less than the design of the modular converter Rated power; the AC side of the modular converter is connected to the load in the station area through an AC circuit breaker to realize power transmission.

The present invention and its preferred versions have the following advantages or beneficial effects:

The invention is used in a flexible interconnection device in a station area, and a modular converter is formed by a plurality of power modules, which can flexibly configure capacity and reduce manufacturing costs. At the same time, through the coordinated control of the flexible interconnection controller in the station area and the power module controller, the adjustment of the output characteristics of multiple power modules and the flexible control of the number of work can be realized, and the operating efficiency and reliability of the system can be improved.

Description of drawings

Below in conjunction with accompanying drawing and specific embodiment the present invention is described in further detail:

Accompanying drawing 1 is the schematic diagram of the flexible interconnection system of two areas of the embodiment of the present invention;

Figure 2 is a schematic diagram of the relationship between the working quantity of power modules and the total output power of the modularized converter according to the embodiment of the present invention.

Detailed ways

Hereinafter, specific embodiments of the present application will be described in detail with reference to the accompanying drawings. According to these detailed descriptions, those skilled in the art can clearly understand the present application and can implement the present application. Without departing from the principle of the present application, the features in different embodiments can be combined to obtain new implementations, or some features in certain embodiments can be replaced to obtain other preferred implementations.

In order to make the features and advantages of this patent more obvious and easy to understand, the following specific examples are given together with the accompanying drawings and described in detail as follows:

As shown in the figure, the control method of the modular converter used for the flexible interconnection device of the station area, the control method includes the flexible interconnection controller of the station area, and also includes a power module controller and not less than one power module Modular converters composed of groups; the flexible interconnection controller in the station area is used for power, voltage and operation mode switching of all modular converters in the flexible interconnection device in the console area; the power module controller generates synchronous control signals to Realize the adjustment of the output characteristics of the modularized converter or control the operating quantity of the power modules; the flexible interconnection controller of the station area and the power module controller are connected by a communication link, and the communication link communication mode includes CAN bus, network cable, A control cable; the power module controller communicates with the power module through the CAN bus.

The working mode of the power module includes an independent working mode and a cooperative control mode; when the power module works in the cooperative control mode, the power module controller generates a synchronous control signal, and controls the power module through the CAN bus to realize multiple The power modules work together.

The power module controller generates a synchronous control signal and a control mode switching command according to the control command of the station area flexible interconnection controller. The control modes include constant voltage and constant frequency control mode, constant power control mode, and constant DC voltage control mode.

The power module controller adjusts the number of power modules put into operation according to the output power of the current modular converter, and reduces power conversion loss by sharing the total output power of the converter equally among the power modules.

The total rated power of the power modules put into operation is greater than 1.2 times the output power of the modular converter.

When the working state of the power module is abnormal, the power module controller disconnects the power module with abnormal working state, and sends the information of the power module with abnormal working state to the flexible interconnection controller in the station area.

The modularized converter used for the flexible interconnection device of the platform area, the modularized converter includes a power module controller, and also includes a modularized converter composed of a plurality of power modules, the circuit topology of the power module Including two-level converter circuit topology, midpoint clamped three-level converter circuit topology, multiple power modules connected in parallel to form a modular converter, the total power of the parallel connected power modules is not less than the design of the modular converter Rated power; the AC side of the modular converter is connected to the load in the station area through an AC circuit breaker to realize power transmission.

Example:

As shown in Figure 1, the schematic diagram of the two-zone flexible interconnection system in this embodiment includes one zone flexible interconnection controller and two modular converters, each of which is composed of 8 power modules , the power module adopts the neutral point clamped three-level topology. The flexible interconnection controller in the station area is used for the power, voltage and operation mode switching of all modular converters in the flexible interconnection device in the console area. The power module controller generates synchronous control signals to adjust the output characteristics of the modular converter. The communication method between the platform flexible interconnection controller and the power module controller adopts the network cable, and the power module controller and the power module communicate through the CAN bus.

The two power module controllers generate synchronous control signals and control mode switching instructions according to the control instructions of the flexible interconnection controller in the station area. The power module controller generates synchronous control signals and controls the output power of the power module through the CAN bus. The power module has an independent working mode and a coordinated control mode.

The power module controller adjusts the working quantity of the power module according to the output power of the current modular converter to reduce the power conversion loss. The relationship between the working number of power modules and the total output power of the modular converter is shown in Figure 2. In this embodiment, the number of power modules is 8, and the power margin of the modular converter is 1 power module. power. When the working state of the power module is abnormal, the power module controller disconnects the abnormal power module, and sends the information of the abnormal power module to the flexible interconnection controller in the station area.

The above description is a preferred embodiment of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of this patent, some improvements and embellishments can also be made. These improvements and Retouching is also considered within the scope of protection of this patent.

This patent is not limited to the above-mentioned optimal implementation mode, and anyone can obtain other various forms of modularized converters and control methods for flexible interconnection devices in the station area under the inspiration of this patent. The equivalent changes and modifications made in the scope of the patent should all fall within the scope of this patent.

Claims (7)

1. The control method for the modularized converter used for the flexible interconnection device in the station area, characterized in that: the control method includes a flexible interconnection controller in the station area, and also includes a power module controller and no less than one power A modular converter composed of modules; the flexible interconnection controller in the station area is used for power, voltage and operation mode switching of all modular converters in the flexible interconnection device in the console area; the power module controller generates synchronous control signals In order to realize the adjustment of the output characteristics of the modular converter or control the number of power modules running; the flexible interconnection controller of the platform and the power module controller are connected by a communication link, and the communication link communication method includes CAN bus, network cable . A control cable; the power module controller communicates with the power module through a CAN bus. 2. The control method for the modular converter of the flexible interconnection device in the station area according to claim 1, characterized in that: the working mode of the power module includes an independent working mode and a cooperative control mode; when the power module When the group works in the cooperative control mode, the power module controller generates a synchronous control signal, controls the power modules through the CAN bus, and realizes the cooperative work of multiple power modules. 3. The control method for the modularized converter used for the flexible interconnection device in the station area according to claim 2, characterized in that: the power module controller generates synchronous A control signal and a control mode switching command, the control modes include constant voltage and constant frequency control mode, constant power control mode, and constant DC voltage control mode. 4. The control method for the modularized converter used for the flexible interconnection device in the station area according to claim 2, characterized in that: the power module controller adjusts the input power according to the output power of the current modularized converter The number of working power modules reduces the power conversion loss by sharing the total output power of the converter equally among the power modules. 5. The control method for the modular converter of the flexible interconnection device in the station area according to claim 4, characterized in that: the power module put into operation has a modularized power greater than 1.2 times its total rated power Converter output power. 6. The control method for the modularized converter used for the flexible interconnection device in the station area according to claim 2, characterized in that: when the working state of the power module is abnormal, the power module controller is disconnected from the working state abnormal power module, and send the information of the power module with abnormal working status to the flexible interconnection controller in the station area. 7. The modularized converter used for the flexible interconnection device in the station area is characterized in that: the modularized converter includes a power module controller, and also includes a modularized converter composed of a plurality of power modules. The circuit topology of the power module includes two-level converter circuit topology and midpoint clamped three-level converter circuit topology. Multiple power modules are connected in parallel to form a modular converter. The total power of the parallel connected power modules is not less than the module The design rated power of the modular converter; the AC side of the modular converter is connected to the station area load through an AC circuit breaker to realize power transmission.

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