Current leakage detector of construction machine

Abstract

The invention relates to a current leakage detector of a construction machine. An inverter is forcibly operated to supply electric power to a motor, thereby performing detection of a current leakage, on condition that a power-on operation is performed, that the motor is stopped, and that determination as to occurrence or non-occurrence of the current leakage has not yet been made even once after the power-on.

Description

technical field [0001] The present invention relates to a leakage detection device for detecting a leakage of a motor drive circuit in a construction machine such as a hybrid excavator or a battery-powered excavator whose electric motor is driven by a battery. Background technique [0002] Conventionally, as a technique for detecting electric leakage of a battery-equipped vehicle such as a hybrid vehicle, it is known to apply a sine wave between a DC bus and the main body (ground) of the machine as shown in Patent Document WO2007 / 007749 , pulse wave, etc. test voltage, and its peak value measurement technology. [0003] In this technique, when a leakage due to poor insulation or the like occurs, the peak value of the test voltage due to the leakage resistance becomes lower than a reference value, and when this low peak value is detected, it is determined as a leakage. [0004] However, when this technique is applied to a construction machine (for example, an excavator. Here...

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Problems solved by technology

Therefore, at this time, there is a high possibility of erroneous detection, such as determining that there is a leakage state even though there is no leakage.

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