Crane apparatus, container yard, and feeding method

1. A crane apparatus comprising:

a first three-phase full-wave rectifier configured to perform full-wave rectification of first three-phase AC power supplied from ground power supply equipment, and to supply obtained DC power to a common bus;

a three-phase transformer configured to output second three-phase AC power of a voltage phase shifted by π/6 from the first three-phase AC power;

a second three-phase full-wave rectifier configured to perform full-wave rectification of the second three-phase AC power output from said three-phase transformer, and to supply obtained DC power to the common bus; and

a motor configured to be driven to hoist and lower a container based on the DC powers supplied from said first and second three-phase full-wave rectifiers to the common bus.

2. The crane apparatus according to claim 1 , wherein said three-phase transformer is constituted by a three-phase transformer of one of a Δ-Y connection type and a Y-Δ connection type.

3. A container yard comprising:

feeder lines extending in a mounting place of a container and configured to feed operating power to a crane apparatus which performs handling of the container; and

a plurality of three-phase transformers provided for said respective feeder lines, and configured to transform a voltage of power-supply power supplied from host power supply equipment, and to supply obtained operating power to said feeder lines,

wherein one of two paired three-phase transformers among said three-phase transformers is constituted by a first three-phase transformer configured to output, as the operating power, first three-phase AC power of the same voltage phase as a voltage phase of the power-supply power, and the other three-phase transformer of said two paired three-phase transformers is constituted by a second three-phase transformer configured to output, as the operating power, second three-phase AC power of a voltage phase shifted by π/6 from the voltage phase of the power-supply power.

4. The container yard according to claim 3 , wherein said first three-phase transformer is constituted by a three-phase transformer of one of a Δ-Δ connection type and a Y-Y connection type, and said second three-phase transformer is constituted by a three-phase transformer of one of a Δ-Y connection type and a Y-Δ connection type.

5. A feeding method used in a crane apparatus that drives a motor to hoist and lower a container based on DC power supplied to a common bus, comprising the steps of:

causing a first three-phase full-wave rectifier to perform full-wave rectification of first three-phase AC power supplied from ground power supply equipment, and to supply obtained DC power to the common bus;

causing a three-phase transformer to output second three-phase AC power of a voltage phase shifted by π/6 from the first three-phase AC power; and

causing a second three-phase full-wave rectifier to perform full-wave rectification of the second three-phase AC power output from the three-phase transformer, and to supply obtained DC power to the common bus.

6. The feeding method according to claim 5 , wherein the three-phase transformer is constituted by a three-phase transformer of one of a Δ-Y connection type and a Y-Δ connection type.

7. A feeding method used in a container yard including feeder lines extending in a mounting place of a container and configured to feed operating power to a crane apparatus which performs handling of the container, and a plurality of three-phase transformers provided for the respective feeder lines, and configured to transform a voltage of power-supply power supplied from host power supply equipment, and to supply obtained operating power to the feeder lines, comprising the steps of:

causing a first three-phase transformer that is one of two paired three-phase transformers among the three-phase transformers to output, as the operating power, first three-phase AC power of the same voltage phase as a voltage phase of the power-supply power; and

causing a second three-phase transformer that is the other three-phase transformer of the two paired three-phase transformers to output, as the operating power, second three-phase AC power of a voltage phase shifted by π/6 from the voltage phase of the power-supply power.

8. The feeding method according to claim 7 , wherein the first three-phase transformer is constituted by a three-phase transformer of one of a Δ-Δ connection type and a Y-Y connection type, and the second three-phase transformer is constituted by a three-phase transformer of one of a Δ-Y connection type and a Y-Δ connection type.