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KR-102963020-B1 - POWER SUPPLYING APPARATUS FOR SHIP AND OVER HEAT PROTECTION METHOD OF POWER SUPPLYING APPARATUS FOR SHIP

KR102963020B1KR 102963020 B1KR102963020 B1KR 102963020B1KR-102963020-B1

Abstract

The present invention aims to provide a ship power supply device and a method for protecting against overheating of a magnetizing transformer without a separate additional device. A ship power supply device according to one embodiment of the present invention may include a main transformer that converts power from a ship generator into a preset power; a magnetizing transformer that receives power from the ship generator and pressurizes the main transformer before the power conversion operation of the main transformer; a switch unit that opens and closes a power transmission path transmitted from the ship generator to the main transformer and the magnetizing transformer, and a pressurization path between the magnetizing transformer and the main transformer; and a protection relay that prevents overheating of the magnetizing transformer by controlling the opening and closing operation of the path of the switch unit according to the temperature of the magnetizing transformer calculated according to the inrush current period of the power supplied from the ship generator. An overheating protection method for a ship power supply device according to one embodiment of the present invention may include the step of the magnetizing transformer receiving power from the ship generator and pressurizing the main transformer; the step of the protection relay calculating the temperature of the magnetizing transformer according to the inrush current period of the power supplied from the ship generator; and the result of the temperature calculation pre- If the set input temperature limit is exceeded, the protective relay may include a step of opening the power transmission path from the ship generator to the ship magnetization transformer.

Inventors

  • 김성일
  • 성병철

Assignees

  • 에이치디현대일렉트릭 주식회사

Dates

Publication Date
20260511
Application Date
20231017

Claims (7)

  1. A main transformer that converts power from a ship generator into preset power; A ship magnetization transformer that receives power from the ship generator and pressurizes the main transformer before the power conversion operation of the main transformer; A switch unit for opening and closing a power transmission path transmitted from the above-mentioned ship generator to the above-mentioned main transformer and the above-mentioned magnetizing transformer, and a pressurization path between the above-mentioned magnetizing transformer and the above-mentioned main transformer; and A protective relay that prevents overheating of the magnetizing transformer by controlling the path opening and closing operation of the switch unit according to the temperature of the magnetizing transformer calculated according to the inrush current period of the power supplied from the ship generator; The above protection relay A temperature calculation unit that calculates the temperature of the line magnetization transformer according to the preset specifications of the line magnetization transformer and the inrush current period; and A judgment unit that determines whether to execute a pressurization operation of the line magnetization transformer according to the calculation result of the temperature calculation unit; Ship power supply unit.
  2. delete
  3. In paragraph 1, The above temperature calculation unit A first RS latch for detecting whether there is an inrush current in the power from the above-mentioned ship generator; A first temperature calculation logic circuit for calculating the temperature of the line magnetization transformer during the period in which the above inrush current occurs; Inrush period calculation logic circuit for calculating the period during which the above inrush current occurs; A second RS latch for detecting the pressurization operation of the above-mentioned magnetizing transformer; A second temperature calculation logic circuit for calculating the temperature of the line magnetization transformer during the pressurization operation of the line magnetization transformer; A third RS latch that detects the interruption of the pressurization operation of the above-mentioned magnetizing transformer; A third temperature calculation logic circuit during the suspension of pressurization operation of the above-mentioned magnetization transformer; and Summing logic circuit that sums the temperature calculation values of the first to third temperature calculation logic circuits above A ship power supply device including
  4. In paragraph 3, The above judgment unit is a ship power supply device that opens the power transmission path from the ship generator to the ship magnetization transformer if the sum result of the sum logic circuit is greater than or equal to a preset input temperature limit.
  5. In paragraph 1, The above-mentioned ship magnetizing transformer is a ship power supply device that pressurizes the secondary side among the primary side receiving power from the ship generator of the above-mentioned main transformer and the secondary side that is magnetically coupled with the primary side and outputs the above-mentioned preset power.
  6. In paragraph 1, The above switch part A first switch that opens and closes the power transfer path between the ship generator and the ship magnetization transformer according to the control of the above protection relay; A second switch that opens and closes the power transfer path between the ship generator and the main transformer according to the control of the above protection relay; and A third switch that opens and closes the pressurization path between the line magnetization transformer and the main transformer according to the control of the above protection relay. A ship power supply device including
  7. A step in which the magnetizing transformer receives power from the ship generator and pressurizes the main transformer; A step in which a protective relay calculates the temperature of the ship magnetization transformer according to the inrush current period of the power supplied from the ship generator; and If the temperature calculation result is greater than or equal to a preset input temperature limit, the protective relay opens the power transmission path from the ship generator to the ship magnetization transformer. Overheating protection method for a ship power supply device including

Description

Power Supplying Apparatus for Ship and Overheat Protection Method for Power Supplying Apparatus for Ship The present invention relates to a ship power supply device and a method for protecting against overheating of a ship power supply device. Generally, ship power supply units use large-capacity transformers, and when these large-capacity transformers are pressurized, an inrush current of several to tens of times the rated current is generated. In the case of ship power supply units, the voltage drop caused by the inrush current is very large due to the low system short-circuit capacity compared to the power grid, resulting in cases where the transient voltage standard is exceeded. As an alternative to this, a method can be adopted in which a low-capacity pre-magnetizing transformer is energized first, and then the main transformer is energized. The aforementioned magnetized transformer is connected to the system for only a short period of time, and since its transformer capacity is very low—at the level of 0.1% to 1% of the main transformer capacity—it is classified as a device of low importance and only protection against overcurrent is provided. When the main transformer is pressurized through the line magnetization transformer, a high current of up to tens of times the rated current of the line magnetization transformer flows through the line magnetization transformer, and this current is greatest at the beginning of the main transformer pressurization and decreases as the pressurization stabilizes. However, if a current significantly exceeding the rated value passes through the line magnetization transformer, the temperature of the transformer windings rises. If the main transformer is re-energized before this temperature has sufficiently cooled, the temperature of the line magnetization transformer windings rises further from the initial high temperature, posing a problem that may lead to thermal damage. FIG. 1 is a schematic diagram of a ship power supply device according to one embodiment of the present invention. FIG. 2 is a schematic diagram of a protective relay of a ship power supply device according to one embodiment of the present invention. FIG. 3 is a flowchart illustrating an overheat protection method for a ship power supply device according to one embodiment of the present invention. FIG. 4 is a diagram showing the overheat protection operation of a ship power supply device according to one embodiment of the present invention. Hereinafter, preferred embodiments are described in detail with reference to the attached drawings so that a person skilled in the art can easily implement the present invention. FIG. 1 is a schematic diagram of a ship power supply device according to one embodiment of the present invention. Referring to FIG. 1, a ship power supply device (100) according to one embodiment of the present invention may include a protection relay (110), a ship magnetization transformer (120), a switch unit (130), and a main transformer (140). The protection relay (110) can control the opening and closing of the power transmission path of the switch unit (130) according to the detection result of the current detector (CT) that detects the state of power supplied from the ship generator (SM) through the main busbar. The protection relay (110) can perform protection operations on the magnetizing transformer (120) and can protect the magnetizing transformer (120) from overcurrent by controlling the opening and closing of the power transmission path of the switch unit (130) according to the detection result of the current detector (CT). In particular, the protection relay (110) can protect the magnetizing transformer (120) from overheating by calculating the temperature of the magnetizing transformer (120) according to the inrush current period of the power from the ship generator (SM) and controlling the opening and closing of the power transmission path of the switch unit (130). The magnetizing transformer (120) can pressurize the main transformer (140) before the main transformer (140) operates. The main transformer (140) may have a primary side that receives power supplied from the ship generator (SM) through the main busbar, and a secondary side that is magnetically coupled with the primary side and outputs power that is pre-set according to the winding ratio with the primary side, and the magnetizing transformer (120) can pressurize the secondary side of the main transformer (140) before the main transformer (140) operates. The magnetizing transformer (120) may be connected to the main busbar for only a short period of time, and the capacity of the magnetizing transformer (120) may be at the level of 0.1% to 1% of the capacity of the main transformer (140). The switch unit (130) can open and close the power transmission path transmitted from the ship generator (SM) to the main transformer (140) and the magnetizing transformer (120), and the pressurization path between the magnetizing