KR-20260062939-A - Electric construction machinery

Abstract

The present invention aims to provide an electric construction machine capable of miniaturizing a hydrogen tank that stores fuel for a fuel cell and a heat exchanger that dissipates heat from the coolant of the fuel cell. To this end, a hydraulic shovel comprising a vehicle body, an electric motor that is a power source for the vehicle body, a fuel cell that generates power, and a power control device that controls the power supplied to the electric motor, wherein the hydraulic shovel comprises an external receiver that receives power from a commercial power supply unit, and the power control device controls the power supplied to the electric motor from the fuel cell and the external receiver.

Inventors

• 오스기 료타
• 야마시타 마사시

Assignees

• 히다찌 겐끼 가부시키가이샤

Dates

Publication Date

20260507

Application Date

20240826

Priority Date

20230906

Claims (6)

1. The car body and, The electric motor, which is the power source of the above vehicle body, and Fuel cells that generate power, and In an electric construction machine equipped with a power control device for controlling power supplied to the above-mentioned electric motor, Equipped with an external receiver that receives power from a commercial power supply, The power control device controls the power supplied to the motor from the fuel cell and the external receiver. Electric construction machine characterized by
2. In paragraph 1, The vehicle body is equipped with an operating device for directing the operation of the vehicle body, and The power control device determines the amount of power supplied from the fuel cell to the motor and the amount of power supplied from the external receiver to the motor based on the required amount of power calculated based on the amount of operation of the operating device. Electric construction machine characterized by
3. In paragraph 2, A battery capable of supplying power to the above-mentioned electric motor is provided, The power control device supplies power to the motor from the battery, the fuel cell, and the external receiver when the required power amount exceeds a first power threshold set based on the combined maximum output value of the external receiver and the battery, or when the required power amount exceeds a second power threshold set based on the combined maximum output value of the external receiver and the fuel cell. Electric construction machine characterized by
4. In paragraph 3, The power control device, when the remaining amount of the battery is below a predetermined first battery threshold during the operation of the motor, supplies power to the motor and the battery from the fuel cell, and also supplies power to the motor and the battery from the external receiver. Electric construction machine characterized by
5. In paragraph 4, The power control device determines whether the remaining amount of the battery is less than a second battery threshold, which is set to be greater than the first battery threshold, when the required power amount is less than or equal to a third power threshold set based on the maximum output value of the external receiver. If it is determined that the remaining amount of the above battery is less than the second battery threshold, power supply from the fuel cell is stopped, and power is supplied to the motor and the battery from the external receiver. If it is determined that the remaining amount of the above battery is greater than or equal to the second battery threshold, power supply from the above battery and the above fuel cell is stopped, and power is supplied to the above motor from the above external receiver. Electric construction machine characterized by
6. In paragraph 5, The power control device determines whether the remaining capacity of the battery is less than a third battery threshold, which is set to be greater than the first battery threshold and less than the second battery threshold, when the required power amount exceeds the third power threshold, and the required power amount is less than the first power threshold and the required power amount is less than the second power threshold. If it is determined that the remaining amount of the above battery is less than the third battery threshold, power is supplied to the motor and the battery from the fuel cell and the external receiver, and If it is determined that the remaining amount of the above battery is greater than or equal to the third battery threshold, power supply from the fuel cell is stopped, and power is supplied to the motor from the battery and the external receiver. Electric construction machine characterized by

Description

Electric construction machinery The present invention relates to an electric construction machine. Conventionally, construction machinery with low greenhouse gas emissions has been developed, and for example, electric construction machinery equipped with fuel cells is being developed. As a document disclosing prior art for electric construction machinery equipped with fuel cells, there is, for example, Patent Document 1. Patent Document 1 describes an electric construction machine having a main body, a first pivoting unit installed between a driving device that drives the main body and pivots the main body, a working device connected to the main body, and a receiving unit pivotable by a second pivoting unit different from the first pivoting unit, wherein the receiving unit accommodates a hydrogen tank that stores hydrogen and a fuel cell that generates power using the hydrogen supplied from the hydrogen tank, and a hydraulic device that drives the working device is arranged in the main body. FIG. 1 is a schematic diagram of a hydraulic shovel in an embodiment of the present invention. FIG. 2 is a configuration diagram of a power control system in an embodiment of the present invention. FIG. 3 is a flowchart showing the processing of a power control device in an embodiment of the present invention. FIG. 4 is a configuration diagram showing a modified example of a power control system in an embodiment of the present invention. FIG. 5 is a flowchart showing a variation of the processing of a power control device in an embodiment of the present invention. Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this embodiment, a hydraulic shovel is applied as an electric construction machine according to the present invention, but the scope of application of the present invention is not limited to a hydraulic shovel and can be applied to other electric construction machines. FIG. 1 is a schematic diagram of a hydraulic shovel in the present embodiment. The hydraulic shovel (100) comprises a crawler-type lower body (101), an upper body (102) rotatably mounted on the lower body (101), and a front work device (103) rotatably mounted on the upper body (102). The lower body (101), the upper body (102), and the front work device (103) constitute the vehicle body of the hydraulic shovel (100). The lower body (101), the upper body (102), and the front work device (103) are each driven by a hydraulic actuator (not shown). A cab (104) for an operator to ride in is installed on the front side of the upper body (102). Inside the cab (104), an operating device (16) for directing the operation of the vehicle body (101 to 103) is provided. The upper slewing body (102) is equipped with a hydraulic pump (1), an electric motor (2), a fuel cell (3), a battery (4), an external receiver (5), a power control device (6), a hydrogen tank (7), a heat exchanger (8), a vehicle body controller (9), etc. The hydraulic pump (1) is driven by the electric motor (2) and supplies hydraulic fluid to each hydraulic actuator. The external receiver (5) is connected to a commercial power supply unit (11) via a power cable (10) and receives power from the commercial power supply unit (11). FIG. 2 is a configuration diagram of an electric drive system mounted on a hydraulic shovel (100). The power control system (200) is equipped with an electric motor (2), a fuel cell (3), a battery (4), an external receiver (5), a power control device (6), a hydrogen tank (7), a heat exchanger (8), a vehicle body controller (9), an operating device (16), and a battery controller (17). The fuel cell (3) is connected to the hydrogen tank (7) through a hydrogen fuel line (12) and generates power by receiving hydrogen fuel from the hydrogen tank (7). The heat exchanger (8) is connected to the fuel cell (3) through a coolant line (13) that circulates coolant (cooling water) and dissipates heat from the coolant that cools the fuel cell (3). The power control device (6) is connected to the fuel cell (3), battery (4), and external receiver (5) via the power line (14), and is connected to the fuel cell (3), battery controller (17), and vehicle body controller (9) via the signal line (15). A signal notifying the required power amount of the motor (2) is input from the vehicle body controller (9) to the power control device (6). The vehicle body controller (9) calculates the required power amount of the motor (2) based on the signal (operation amount) input from the operating device (16). The battery controller (17) determines the state of the battery (4) (whether power supply is possible and whether charging is possible) by measuring the remaining amount or temperature of the battery (4). A signal indicating the state of the battery (4) (battery status signal) is input from the battery controller (17) to the power control device (6). A signal instructing the power generation or stopping of the fuel cell (3) is input from the powe