With the deepening implementation of the green and low-carbon development strategy

electrification transformation has been widely promoted in major ports across China.However

after that large-scale logistics handling equipment

such as quay cranes and yard cranes

are connected to the port distribution network

their short-term high-power characteristics can cause severe fluctuations in load power

and then significantly increases the current total harmonic distortion at the primary node of the distribution network.With the rise in total harmonic distortion

transformers will endure greater harmonic-induced additional losses

which

under long-term operation

accelerate aging and ultimately shorten their service lifespan.Based on the mapping relationship between harmonic distortion rate and transformer lifespan

this paper proposes a multioperatingcondition-coupled dynamic evaluation model for the harmonic impact of quay cranes

quantifying the contribution of access location

equipment quantity

and operating state to the harmonic distortion rate at the primary node of the distribution network.First

based on the actual operating motion patterns of quay crane devices

a simulation model of quay cranes and yard cranes is constructed in Simulink using the asynchronous motor module to analyze the harmonic characteristics of port logistics handling equipment in practical engineering.Second

the impact of different operating conditions of the quay cranes on the harmonic current distortion rate at the primary common node of the distribution network and the lifespan of port transformers is quantified.Finally

simulation results based on the IEEE-14 bus distribution network system demonstrate that the proposed method accurately quantifies harmonic distortion rate under various operating conditions

providing theoretical support for maintenance personnel in formulating transformer harmonic suppression strategies and extending equipment lifespan.