TW202101140A - DC ship micro-grid protection device design system capable of analyzing various short-circuit currents, a magnitude of the short-circuit current flowing through each feeder, and a system voltage of each feeder to determine recommended specifications - Google Patents

Abstract

The invention relates to a DC ship micro-grid protection device design system, which mainly provides planning in advance for a ship owner. Before a ship power distribution network is built, in response to input of a power distribution network design drawing and parameters of each component, a processing unit analyzes occurrences of various short-circuit currents, a magnitude of the short-circuit current flowing through each feeder, and a system voltage of each feeder in view of an entire system. The invention can analyze recommended specifications of protection devices of each feeder as a reference for the ship owner to purchase and build the protection device.

Description

Design system of DC ship micro-grid protection device

The creation of the present invention relates to a specification suggestion system, especially a design system for a DC marine micro-grid protection device.

System failure protection is extremely important to the safe operation and operation of ships, mainly because when the ship is sailing, if there is an abnormality in the power supply network, the entire ship will stop moving, and at worst, it will cause greater disasters due to electric wires. Shorter, the DC fault current will have a higher peak value, and the rate of rise of the fault current is also higher. Its magnitude has a great relationship with the capacitor configuration in the DC system and the power converter and the capacity of the battery energy storage system. Fault current analysis must be able to consider these factors to correctly estimate the short-circuit current related information when a DC fault occurs in the system, including at least the current peak value and time constant, which can be used as a reference for determining the appropriate protection device capacity and protection coordination. The basis of proper fault detection isolation recovery strategy. However, most of the DC protection devices of the general DC ship power supply network choose power fuses or circuit breakers. The advanced DC ship micro-grid system protection devices have gradually changed from traditional fuses and circuit breakers to solid-state protection switch technology. The consideration is that the protection device must act fast enough to disconnect the DC fault current in a very short time and maintain the non-faulty area of the system to continue to supply power. The protection speed of DC marine power system is limited by factors such as fault detection and location speed, communication transmission delay, protection device or circuit breaker operation time. Generally speaking, fast fault disconnection speed requires higher cost protection devices, but if the fault disconnection speed is slow, it will require power electronic equipment to have higher short-circuit thermal tolerance, which may also lead to higher equipment costs. high. In order to realize the design of a DC ship power protection system that takes into account economy and efficiency, it is often necessary to make a compromise between high fault disconnection speed and low fault disconnection current. In terms of system planning and design, the overall consideration and evaluation of different protection system software and hardware equipment schemes and their corresponding fault protection and power recovery strategies can meet the requirements of different levels of protection systems and power supply reliability of shipyards or shipowners. Based on the above-mentioned problems, the author believes that there should be a system that can be proposed before considering the DC power supply system to provide advice on the purchase specifications of the shipowner's protective device. Therefore, the author began to think about its solution.

In view of the shortcomings described in the prior art, the creator of the present invention proposes a DC ship micro-grid protection device design system, including: One input: The input terminal can be used to input a power distribution network design drawing. The power distribution network design drawing includes a DC power supply unit, a main feeder electrically connected to the DC power supply unit, a bus bar connected to the main feeder, and an electrical connection The first and second branch feeders of the bus bar, a first load electrically connected to the first branch feeder, and a second load electrically connected to the second branch feeder, current input terminal of the first branch feeder A first protection device and a first power converter are provided, a second protection device and a second power converter are provided at the current input end of the second branch feeder, and a third protection device and a third power converter are provided on the main feeder Power converter; the input terminal can be used to input the first power data of the first load, the second power data of the second load, the impedance data of the first branch feeder of the first branch feeder, and the second branch feeder The second branch feeder impedance data, the main feeder impedance data of the main feeder, the bus impedance data of the bus, the output power data of the DC power supply unit, the first capacitance of a first power converter, The second capacitance of a second power converter and the third capacitance of a third power converter. One output unit. One processing unit: The processing unit is electrically connected to the input terminal and the output unit. The processing unit writes a protection device suggestion program that can be executed by the processing unit: analyze the generation of multiple short-circuit currents according to the power distribution network design drawing Factors, for each short-circuit current generating factor, the first and second power data, the first and second branch feeder impedance data, the main feeder impedance data, the bus impedance data, the output power data, and the first to The third capacitance analyzes the recommended data of the first protection device specification of the first protection device, the second protection device specification data of the second protection device, and the third protection device specification data of the third protection device. Control the output unit to output the recommended specifications of the first to third protection devices. Therefore, through this creation, we can analyze the possible conditions of the occurrence of various short-circuit currents based on the power distribution network design drawing, and then analyze the recommended data of the first to third protection device specifications with various parameters to analyze the power distribution The value of the fault current that may occur in each feeder, bus, etc. in the network, and then judge the recommended data of the first to third protection device specifications based on the analysis result. Therefore, this creation is based on the precautionary approach. Before the completion of the ship and its distribution and power supply network, it will analyze various possible short-circuit current conditions based on the distribution network design drawing to generate recommended data for the protection device specifications as the ship owner. Reference basis when purchasing protection devices.

With the aid of the drawings, the structure, characteristics and embodiments of the invention are described below, so that your examiners can have a better understanding of the invention. Please refer to the first picture in conjunction with the second and third pictures. This creation is about a DC ship micro-grid protection device design system, including: One input (1): The input terminal (1) can be used to input a power distribution network design drawing (A), the power distribution network design drawing (A) includes: a direct current power supply unit (A1), a direct current power supply unit (A1) electrically connected to the The main feeder (A2), a bus (A7) electrically connected to the main feeder (A2), and the first and second branch feeders (A3, A4) electrically connected to the bus (A7), one electrical A first load (A5) connected to the first branch feeder (A3), a second load (A6) electrically connected to the second branch feeder (A4), and the current input terminal of the first branch feeder (A3) is set A first protection device and a first power converter (A8), the current input end of the second branch feeder (A4) is provided with a second protection device and a second power converter (A9), the main feeder (A2) ) Set up a third protection device and a third power converter. Moreover, the input terminal (1) can be used to input the first power data of the first load (A5), the second power data of the second load (A6), and the main feeder impedance data of the main feeder (A2) , A first branch feeder impedance data of the first branch feeder (A3), a second branch feeder impedance data of the second branch feeder (A4), a bus impedance data of the bus (A7), the DC The output power data of the power supply unit (A1), the first capacitance data of a first power converter (A8), the second capacitance data of a second power converter (A9), and a third power converter The third capacitance information. An output unit (2); The output unit (2) can output the suggested results of the system, so the output unit (2) can be a display, photocopier, handheld device, etc. One processing unit (3): The processing unit (3) is electrically connected to the input terminal (1) and the output unit (2). The processing unit (3) is written with a protection device recommendation program (31), and the protection device recommendation program (31) can For the processing unit (3) to execute: analyze the multiple short-circuit current generating factors according to the distribution network design drawing (A7), and match the first and second power data, the first and second branch feeders to each short-circuit current generating factor Impedance data, the main feeder impedance data, the bus impedance data, the output power data, and the first to third capacitances are analyzed to obtain a first protection device specification recommendation data of the first protection device, and the second protection device The second protection device specification data, the third protection device specification data of the third protection device, and then the output unit (2) is controlled to output the first to third protection device specification data. Among them, the aforementioned factors include: the DC power supply unit (A1), the main feeder (A2), the bus bar (A7), the first and second branch feeders (A3, A4), the first load (A5), the second load (A6) and other parts are short-circuited or damaged. The following is a detailed description of the implementation of the protective device recommended program (31) in conjunction with the second figure. First of all, it must be explained in advance that the protective device recommended program (31) is mainly analyzed from the point of view of the system to obtain the The recommended data of the protection device specifications of the main feeder, the first branch feeder and the second branch feeder are analyzed in advance to provide the shipowner with a reference basis for purchasing each protection device when building the ship and its power distribution network . The following will introduce one of the components damaged to introduce the work flow of this creation. First, the processing unit (3) will first assume that the first load (A5) is faulty, and then cooperate with the first and second power data, the first and second branch feeder impedance data, the main feeder impedance data, and the confluence The row impedance data, the output power data, and the first to third capacitances are analyzed from the perspective of the overall system, and analyzed to obtain the flow through the main feeder (A2), the first branch feeder (A3), and the second Each short-circuit current of two branch feeders (A5). Then, according to the above process, it is assumed that when the second load (A6), the bus bar (A7), the main feeder (A2), the first branch feeder (A3), the second branch feeder (A4), and the When the generator set (A1) and other parts are short-circuited or damaged, the short-circuit current and the short-circuit current rise rate flowing through each main feeder (A2), the first branch feeder (A3), and the second branch feeder (A5) under various conditions ; After all analysis is over, among the analysis results, the lowest value of the short-circuit current flowing through the main feeder (A2) is used as the basis for judgment to estimate the first breaking current recommendation data, and analogously, judge a The second and third recommended breaking current data; and the highest value of the short-circuit current rise rate flowing through the main feeder (A2) is used as the judgment basis to estimate a first response time suggestion data, the same goes for judgment Provide a second and third response time suggestion data, in order to avoid problems such as too fast rise of short-circuit current and too slow response of the protection device. Therefore, the recommended data for the first protection device specification includes the first recommended breaking current data and the first recommended response time; the second recommended protection device specification data includes the second recommended breaking current data and the The second reaction time suggestion data; the third protection device specification suggestion data includes the third start-off current suggestion data and the third reaction time suggestion data. It can be seen from the above that this creation is a precautionary approach. Before the completion of the ship and its distribution and power supply network, the system can be analyzed in advance, and the protection device specifications of each feeder can be obtained, so that the shipowner can build The reference basis for choosing protection devices when installing the ship's power supply network, in order to avoid the occurrence of the protection device being difficult to perform its due function, or the purchase of inappropriate protection devices which may cause waste or regret. In summary, the creation of the present invention is indeed in line with industrial applicability, and has not been seen in publications or publicly used before the application, and has not been known to the public, and it is non-obvious and easy to know, and meets the requirements of patentability. Application. However, the foregoing is a preferred embodiment of the invention creation in the industry. All the equivalent changes made in accordance with the scope of the patent application for the invention creation belong to the scope of the claims of this case.

(A): Distribution network design drawing (A1): DC power supply unit (A2): Main feeder (A3): The first branch feeder (A4): The second branch feeder (A5): First load (A6): Second load (A7): Busbar (A8): The first power converter (A9): Second power converter (1): Input terminal (2): Output unit (3): Processing unit (31): Protective device recommendation program

The first picture is a block diagram of the components of this creation The second picture is the work flow chart of this creation The third figure is a schematic diagram of the distribution network

(1): Input terminal

(2): Output unit

(3): Processing unit

(31): Protective device recommendation program

Claims (3)

A DC ship micro-grid protection device design system, including: One input terminal: for inputting a power distribution network design drawing, the power distribution network design drawing includes a DC power supply unit, a main feeder electrically connected to the DC power supply unit, a bus bar connected to the main feeder, and an electrical The first and second branch feeders connected to the bus bar, a first load electrically connected to the first branch feeder, and a second load electrically connected to the second branch feeder, the current input of the first branch feeder A first protection device and a first power converter are provided at the end, a second protection device and a second power converter are provided at the current input end of the second branch feeder, and a third protection device and a second power converter are provided on the main feeder. Three power converters; the input terminal can be used to input the first power data of the first load, the second power data of the second load, the first branch feeder impedance data of the first branch feeder, and the second branch The second branch feeder impedance data of the feeder, the main feeder impedance data of the main feeder, the bus impedance data of the bus, the output power data of the DC power supply unit, the first capacitance of a first power converter Data, second capacitance data of a second power converter, and third capacitance data of a third power converter; An output unit; A processing unit: respectively electrically connected to the input terminal and the output unit, the processing unit writes a protection device suggestion program, the protection device suggestion program can be executed by the processing unit: analyze the complex short-circuit current according to the distribution network design drawing The generating factors, for each short-circuit current generating factor, match the first and second power data, the first and second branch feeder impedance data, the main feeder impedance data, the bus impedance data, the output power data, and the first To the third capacitance analysis, a first protection device specification data of the first protection device, a second protection device specification data of the second protection device, and a third protection device specification data of the third protection device are obtained. Then control the output unit to output the recommended specifications of the first to third protection devices. For example, the DC marine microgrid protection device design system described in the scope of patent application, wherein the first protection device specification data includes a first breaking current recommendation data, and the second protection device specification data includes a second The recommended data for breaking current, the recommended data for the third protection device specification includes a third recommended data for breaking current; the recommended program for the protection device can be executed by the processing unit: assuming the first load, the second load, and the confluence When a short-circuit condition or a damage condition occurs to the row, the main feeder, the first branch feeder, the second branch feeder, or the DC power supply unit, according to the first power data, the second power data, and the first branch feeder Impedance data, the second branch feeder impedance data, the main feeder impedance data, the bus impedance data, and the output power data, respectively, analyze the plural first short-circuit currents flowing through the main feeder in each condition, and flow through each condition The plural second short-circuit currents of the first branch feeder and the plural third short-circuit currents flowing through the second branch feeder under various conditions, the lowest of each of the first short-circuit currents is used as the basis of judgment to estimate the first breaking current recommendation According to the data, the lowest one of the second short-circuit currents is used as the basis of judgment to estimate the second recommended breaking current data, and the lowest of the third short-circuit currents is used as the basis of judgment to estimate the third recommended breaking current. For example, the DC marine micro-grid protection device design system described in item 2 of the scope of patent application, wherein the first protection device specification data includes a first response time recommendation data, and the second protection device specification recommendation data includes a second response Time suggestion data, the third protection device specification suggestion data includes a third response time suggestion data; the protection device suggestion program can be executed by the processing unit: assuming the first load, the second load, the bus, the When the main feeder, the first branch feeder, the second branch feeder, or the DC power supply unit is short-circuited or damaged, according to the first power data, the second power data, the first branch feeder impedance data, and the Two branch feeder impedance data, the main feeder impedance data, the bus impedance data, and the output power data, respectively analyze the plural first short-circuit current rise rate flowing through the main feeder under each condition, and the first The second short-circuit current rise rate of the branch feeder, and the second short-circuit current rise rate of the second branch feeder under various conditions, the highest of each first short-circuit current is used as the basis of judgment to estimate the first response time suggestion According to the data, the highest second short-circuit current is used as the judgment basis to estimate the second reaction time suggestion data, and the highest each third short-circuit current is used as the judgment basis to estimate the third reaction time suggestion data.

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