JP5448781B2 - Marine power supply for ship - Google Patents

Description

  The present invention relates to a marine power supply apparatus for a ship for supplying electric power from a land to a ship while the ship is anchored, for example.

  Conventionally, electric power supplied to various electrical devices mounted on a ship has been supplied from a generator mounted on the ship, regardless of whether the ship is sailing or anchored. However, in recent years, in consideration of the global environment, in order to reduce exhaust gas emissions, when a ship enters a port, the ship's generator is stopped and power is supplied to the ship from a power supply device placed on land. Has come to supply.

  When switching the power supply system from the ship's generator to the onshore power supply, the power supply to the load is stopped for a short time unless there is an uninterrupted switching, which may cause problems for information devices in the ship. For this reason, after adjusting the output of the ship's generator to the onshore power supply, turning on the onshore power supply and performing the parallel operation of the ship generator and the onshore power supply for a short time, (See, for example, Patent Document 1).

Japanese Patent Laying-Open No. 2005-237151 (page 6-8, FIG. 1)

  The method described in Patent Document 1 is effective only when the output frequency of the ship generator and the frequency of the onshore power source are the same (usually 60 Hz), and the frequency and voltage of the onshore power source are stable. Otherwise, the above-mentioned synchronization adjustment at the time of switching the system takes time and is difficult.

  However, if the output frequency of the ship's generator and the frequency of the onshore power supply are not the same, it is necessary to match the output frequency of the ship's generator and the frequency of the onshore power supply.

  The present invention has been made to solve the above-described problems. It is possible to match the output frequency of the ship's generator with the frequency of the onshore power source, and to perform system switching relatively easily. An object of the present invention is to provide a marine onshore power supply device.

In order to achieve the above object, a marine power supply apparatus for a ship according to the present invention is a ship power supply apparatus that supplies power from land to a ship via an output switch, and the voltage of the AC power supply is set to a different voltage / frequency. A power converter for converting the power converter, an AC filter provided between the output of the power converter and the switch, a control means for controlling an output frequency and an output voltage of the power converter, and the switch A first voltage detector provided on the input side, a second voltage detector provided on the output side of the switch, and a third voltage detector for directly detecting the output voltage of the generator; And the control means outputs the output of the switch when the generator in the ship is supplying power to the load equipment in the ship and the output switch is open. In the state connected to the output frequency of the power converter Phase control is performed such that the frequency of the detection voltage of the second voltage detector is the same frequency and the phase deviation is minimized, and the detection voltage of the first voltage detector and the frequency of the second voltage detector are Voltage control is performed so that the voltage deviation from the detection voltage is minimized, and when the phase deviation is smaller than a predetermined value and the voltage deviation is smaller than a predetermined threshold, the output switch is turned on, and then the ship In the state where the power generator is disconnected and the power converter is operated without load while the power converter is supplying power to the load equipment in the ship, the output frequency of the power converter and the third The phase of the voltage detector is controlled so that the frequency of the detected voltage is the same frequency and the phase deviation is minimized, and the detected voltage of the first voltage detector and the detected voltage of the third voltage detector are Minimum voltage deviation And voltage control so that the phase deviation is smaller than a predetermined value, and when the voltage difference is smaller than a predetermined threshold value, that is the incorporation of the generator, and adapted to subsequently open the output switch It is characterized by.

  According to the present invention, it is possible to provide a marine power supply device for a ship that can match the output frequency of a ship's generator and the frequency of an onshore power supply and that can perform system switching relatively easily. Become.

1 is a circuit configuration diagram of a marine power supply device for a ship according to Embodiment 1 of the present invention. The flowchart (the 1) of the system | strain switching operation | movement of the onshore power supply apparatus for ships which concerns on Example 1 of this invention. The flowchart (the 2) of the system | strain switching operation | movement of the land power supply device for ships which concerns on Example 1 of this invention. The circuit block diagram of the marine power supply apparatus for ships which concerns on Example 2 of this invention. The circuit block diagram of the marine power supply apparatus for ships which concerns on Example 3 of this invention. The flowchart of the system | strain switching operation | movement of the onshore power supply device for ships which concerns on Example 3 of this invention. The circuit block diagram of the power converter of the land power unit for ships which concerns on Example 4 of this invention. The circuit block diagram of the unit inverter of the power converter of Example 4. FIG.

  Embodiments of the present invention will be described below with reference to the drawings.

  Hereinafter, a marine onshore power supply apparatus according to Embodiment 1 of the present invention will be described with reference to FIGS. 1 to 3.

  1 is a circuit configuration diagram of a marine onshore power supply apparatus according to Embodiment 1 of the present invention.

  The three-phase AC voltage supplied from the AC power source 1 is converted into an appropriate voltage by the input transformer 2 and supplied to the power converter 3. Depending on the specifications of the power converter 3, the input transformer 2 can be omitted. For example, if the frequency of the AC power supply 1 is 50 Hz, the power converter 3 converts this to 60 Hz, which is the frequency of the marine power supply, and enables the rated voltage of the marine power supply to be output. For this reason, the power converter 3 is controlled by the control unit 4. The output of the power converter 3 is connected to the connection point P with the ship side through the AC filter 5 and the output switch 6. A current detector 7 is provided on the input side of the AC filter 5, and a voltage detector 8A is provided on the output side. A voltage detector 8B is provided on the output side of the output switch 6. These detection signals are given to the control unit 4.

  The output of the generator 10 in the ship is connected to the load device 12 via the switch 11, and the normal generator 10 supplies power to the load device 12 via the switch 11. In addition, the load device 12 is connected to the connection point P via the switch 13 so that power can be supplied to the load device 12 from the land.

  Hereinafter, the internal configuration of the control unit 4 will be described. The phase synchronization circuit 41 is basically given the same frequency as the output frequency of the onboard generator 10 as the f command. Then, the frequency is detected by the frequency detector 46 from the voltage detected by the voltage detector 8B, and is supplied to the phase synchronization circuit 41. The phase synchronization circuit 41 operates as a so-called PLL (Phase Locked Loop) circuit, and outputs a frequency having the same phase as the frequency detected by the frequency detector 46 to the V generation circuit 42.

  In the V generation circuit 42, a voltage command corresponding to the given frequency is output and given to the PWM circuit 43. The PWM circuit 43 performs on / off control of switching elements inside the power converter 3 (not shown) so that the output of the power converter 3 becomes a three-phase voltage having a given frequency. In this way, the output voltage of the power converter 3 is controlled to a desired value, but the voltage applied to the connection point P or the load device 12 is the output current of the power converter 3 due to the impedance drop of the filter 5 or the line. Decreases almost proportionally. Therefore, the output of the current detector 7 is given to the voltage correction circuit 44, and the voltage correction circuit 44 outputs an appropriate correction voltage reference according to the output current of the power converter 3, and the output voltage command of the V generation circuit 42 is output. To be added to.

  In order to switch the power supply of the load device 12 from the generator 10 to the power converter 3, it is necessary to match both voltages. Therefore, the voltage detected by the voltage detector 8A and the voltage detector 8B is supplied to the voltage controller 45. The voltage controller 45 outputs an appropriate voltage control command to the V generation circuit 42 according to the deviation between the two voltages. In the V generation circuit 42, the above-described voltage command is corrected, and as a result, the deviation between the two voltages is minimized.

  The voltage detected by the voltage detector 8A and the voltage detector 8B is also input to the voltage coincidence detection circuit 47. When the voltage difference between the two becomes equal to or less than a predetermined threshold, the voltage coincides with the voltage coincidence detection circuit 47. Is supplied to the AND circuit 49. Similarly, the output of the frequency detector 46 and the output of the phase synchronization circuit 41 are given to the phase coincidence detector 48, and when the phase difference between the two becomes a predetermined value or less, the phase coincidence detector 48 outputs 1. This is given to the AND circuit 49.

  The synchronous switching operation of the above-described marine onshore power supply apparatus according to the first embodiment of the present invention will be described with reference to FIGS. FIG. 2 is a flowchart (part 1) of the system switching operation of the marine onshore power supply apparatus according to the first embodiment of the present invention.

  In FIG. 2, first, after the ship is anchored at the port, the main circuit is connected by a cable at point P in FIG. 1 (step S10). At this time, the switch 6 and the switch 13 are open, and the generator 10 supplies power to the load device 12 via the switch 11.

  Next, the power converter 3 is operated in a no-load state (step S11), and the switch 13 is turned on (step S12). As a result, the output voltage of the generator 10 is obtained via the voltage detector 8B, and the output frequency of the power converter 3 including the phase is generated by the operations of the phase synchronization circuit 41 and the voltage control circuit 45 described above. The detection frequency of the voltage detector 8A coincides with the detection voltage of the voltage detector 8B. Therefore, the output of the AND circuit 49, which is a synchronization detection circuit, becomes 1 (step S13).

  Then, the switch 6 is turned on by the synchronization detection signal of the AND circuit 49, and the generator 10 and the power converter 3 are operated in parallel (step S14). Since this parallel operation can be performed in a short time, for example, the switch 11 is opened using the make signal of the auxiliary contact of the switch 6 as a trigger (step S15), and the switching operation is completed. In this case, it is necessary to exchange signals between the land side and the ship, but the illustration is omitted in FIG.

  FIG. 3 is a flowchart (part 2) of the system switching operation of the onshore power supply device for a ship according to the first embodiment of the present invention. 3 is different from FIG. 2 in that the step of fixing the voltage / phase in this state (step S13A) is added after the synchronization detection is performed in step S13.

  In the flowchart of FIG. 2, after the synchronous detection in step S13, if the switch 6 is turned on by moving to step 14 while taking advantage of the closed loop control of the frequency and the closed loop control of the voltage, the control system may be disturbed in some cases. , Current and the like may exceed the allowable fluctuation amount. On the other hand, as shown in the flowchart of FIG. 3, after detecting the synchronization in step S13, the outputs of the phase synchronization circuit 41 and the voltage control circuit 45 are fixed to the phase and voltage in that state in step 13A, respectively, and open loop. When the control state is shifted to step 14 and the switch 6 is turned on, it is possible to avoid the disturbance of the control system due to the closed loop control. It should be noted that the transition to the open loop control may be performed only in either phase or voltage.

  As described above, according to the present embodiment, the uninterrupted system switching from the generator 10 to the power converter 3 can be performed relatively easily. This is because the frequency converter and the voltage control can be performed with desired response characteristics because the power converter 3 is a static converter. In addition, the above advantages are also utilized in other embodiments described below.

  FIG. 4 is a block diagram of a marine onshore power supply apparatus according to Embodiment 2 of the present invention. Regarding the respective parts of the second embodiment, the same parts as those of the marine onshore power supply apparatus according to the first embodiment of the present invention shown in FIG. The difference between the second embodiment and the first embodiment is that when the output of the current detector 7 exceeds a predetermined value, a current controller 50 having a function of adding a negative correction to the voltage command according to the output is provided. Is a point.

  The current controller 50 operates to reduce the output voltage of the power converter 3 when the current becomes excessive due to factors such as additional activation of the load device 12 during operation of the power converter 3. Therefore, it is possible to prevent a trip or the like from occurring due to the protection function of the power converter 3 due to a load variation of the load device 12 or the like.

  Hereinafter, a marine power supply apparatus according to a third embodiment of the present invention will be described with reference to FIGS. 5 and 6.

  FIG. 5 is a block diagram of a marine onshore power supply apparatus according to Embodiment 3 of the present invention. About each part of this Example 3, the same part as each part of the land power unit for ships which concerns on Example 1 of this invention of FIG. 1 is shown with the same code | symbol, and the description is abbreviate | omitted. The third embodiment is different from the first embodiment in that a voltage detector 14 for directly detecting the output voltage of the generator 10 is provided, and the output of the voltage detector 8B is connected to the voltage controller via the switch 51. 45 and the voltage coincidence detector 47, and the input of the switch 51 can be switched between the output of the voltage detector 8B or the output of the voltage detector 14.

  The reason why such a configuration is adopted in the present embodiment is to enable switching from the state where power is supplied to the load device 12 by the power converter 3 to power supply from the generator 10 without interruption. . Hereinafter, the above switching operation will be described according to the flow chart of the system switching operation of the marine onshore power supply apparatus according to the third embodiment of the present invention shown in FIG.

  First, the signal line at point Q in FIG. 5 is connected (step S20). This signal line connection is usually already made when the main circuit is connected in the first embodiment. Next, the generator 10 is operated (step S21). Next, the switch 51 is switched from the land side to the inside of the ship (step S22). As in step S13 of the first embodiment, the operation of the phase synchronization circuit 41 and the voltage control circuit 45 causes the output frequency of the power converter 3 to match the output frequency of the generator 10 including its phase. The detection voltage of the voltage detector 8A matches the detection voltage of the voltage detector 14. Therefore, the output of the AND circuit 49, which is a synchronization detection circuit, becomes 1 (step S23). Further, the switch 11 is turned on in a synchronized state (step S24), and a short time parallel operation is performed. Finally, the switch 6 is opened by a make signal of the switch 11 (step S25), and the power source switching from the power converter 3 to the generator 10 is completed.

  In the above, like the method of step 13A shown in FIG. 3 in the first embodiment, after the synchronization detection in step S23, the phase and voltage of the state are fixed to avoid disturbance of the control system due to the closed loop control. Also good. Further, in the first embodiment, when the power supply from the land by the power converter 3 is performed in an open loop using the method of step 13A of FIG. 3, the control is returned to the closed loop control before step S23 of FIG. It is necessary to keep.

  In the case of this embodiment, although not shown in FIG. 5, since the switch 11 is turned on by the output of the AND circuit 49, it is necessary to exchange the signal between the land side and the inside of the ship. The same applies to the parallel operation confirmation signal.

  Hereinafter, a marine onshore power supply apparatus according to Embodiment 4 of the present invention will be described with reference to FIGS.

  FIG. 7 is a circuit configuration diagram showing a power converter of a marine onshore power supply apparatus according to Embodiment 4 of the present invention. FIG. 7 also shows an input transformer dedicated to the power converter of this embodiment.

  The primary side of the input transformer 2 is connected to the AC power source 1, and the secondary side has a plurality of secondary windings that are multiples of three. A unit inverter 3T (3U1, 3U2, 3U3, 3V1, 3V2, 3V3, 3W1, 3W2, 3W3) is connected to each of these secondary windings. As shown in FIG. 8, these unit inverters 3T are composed of a rectifier 31 that converts a three-phase AC input into DC, a capacitor 32 that smoothes the DC voltage, and an inverter 33 that converts DC into single-phase AC. Has been.

  The outputs of the unit inverters 3U1, 3U2 and 3U3 are connected in series. Similarly, the outputs of the unit inverters 3V1, 3V2 and 3V3 and the unit inverters 3W1, 3W2 and 3W3 are connected in series. And one end of these series connection bodies is mutually connected as a neutral point, and the other end is used as the AC output of the power converter 3.

  Here, the output frequencies of the unit inverters 3T are all the same, the outputs of the unit inverters 3T constituting the series connection body have the same phase, and the phase difference from the unit inverters T belonging to other series connection bodies Are 120 degrees to each other. In FIG. 7, the number of unit inverters 3T connected in series is 3, but may be an arbitrary value.

  The merit of applying the serial multiple inverter shown in FIG. 7 described above to the power converter 3 is that the power supply voltage required by the ship, that is, the voltage that matches the output voltage of the generator 10 can be supplied relatively easily. Because of that. For this purpose, the rated output voltage of the unit inverter and the series number thereof may be appropriately selected. For example, when there is a request of 6 kV, the phase voltage becomes 1/3 of this √3. Therefore, the unit inverter may be set to a rated output voltage of 580 V and the number of series may be set to 6. If such a serial multiple inverter is applied, the output harmonics are reduced, so that the capacity of the AC filter 5 can be reduced.

DESCRIPTION OF SYMBOLS 1 AC power supply 2 Input transformer 3 Power converter 4 Control apparatus 5 AC filter 6, 11, 13 Switch 7 Current detector 8A, 8B, 14 Voltage detector 10 Generator 12 Load apparatus 3T, 3U1, ..., 3W3 Unit inverter 31 Rectifier 32 Capacitor 33 Inverter 41 Phase synchronization circuit 42 V generation circuit 43 PWM circuit 44 V correction circuit 45 Voltage controller 46 Frequency detector 47 Voltage coincidence detection circuit 48 Phase coincidence detection circuit 49 AND circuit 50 Current controller 51 Switch

Claims (5)

An onshore power supply device for a ship that supplies electric power from land to a ship via an output switch,
A power converter for converting the voltage of the AC power source into a different voltage / frequency;
An AC filter provided between the output of the power converter and the switch;
Control means for controlling the output frequency and output voltage of the power converter;
A first voltage detector provided on the input side of the switch;
A second voltage detector provided on the output side of the switch ;
A third voltage detector for directly detecting the output voltage of the generator ;
The control means includes
In the state where the generator in the ship is supplying power to the load equipment in the ship and the output switch is open and the output of the switch is connected to the output side of the generator, the power conversion Phase control so that the output frequency of the detector and the frequency of the detection voltage of the second voltage detector are the same frequency and the phase deviation is minimized, and the detection voltage of the first voltage detector and the second voltage detector The voltage is controlled so that the voltage deviation from the detected voltage of the voltage detector is minimized,
When the phase deviation is smaller than a predetermined value and the voltage deviation is smaller than a predetermined threshold, the output switch is turned on, and then the generator in the ship is disconnected ; and
In the state where the power converter is operating the load generator in the load without supplying power to the load equipment in the ship, the output frequency of the power converter and the frequency of the detection voltage of the third voltage detector are the same. The phase is controlled so that the phase deviation is minimized at the frequency, and the voltage is controlled so that the voltage deviation between the detection voltage of the first voltage detector and the detection voltage of the third voltage detector is minimized. ,
When the phase deviation is smaller than a predetermined value and the voltage deviation is smaller than a predetermined threshold, the generator is inserted, and then the output switch is opened. Power supply. An onshore power supply device for a ship that supplies electric power from land to a ship via an output switch,
A power converter for converting the voltage of the AC power source into a different voltage / frequency;
An AC filter provided between the output of the power converter and the switch;
Control means for controlling the output frequency and output voltage of the power converter;
A first voltage detector provided on the input side of the switch;
A second voltage detector provided on the output side of the switch,
The control means includes
In the state where the generator in the ship is supplying power to the load equipment in the ship and the output switch is open and the output of the switch is connected to the output side of the generator, the power conversion Phase control so that the output frequency of the detector and the frequency of the detection voltage of the second voltage detector are the same frequency and the phase deviation is minimized, and the detection voltage of the first voltage detector and the second voltage detector The voltage is controlled so that the voltage deviation from the detected voltage of the voltage detector is minimized,
When the phase deviation is smaller than a predetermined value and the voltage deviation is smaller than a predetermined threshold, the output switch is turned on, and then the generator in the ship is disconnected ,
A marine power supply device for a ship comprising voltage correction means for correcting an output voltage of the power converter in accordance with an output current of the power converter . The control means includes
When the phase deviation is smaller than a predetermined value and the voltage deviation is smaller than a predetermined threshold, at least one of the phase in the phase control and the voltage in the voltage control is fixed, and then the output switch is turned on The land power supply device for a ship according to claim 1 or 2 , wherein A current detector for detecting an output current of the power converter;
The land for ships according to claim 1 or 2, wherein when the output current detected by the current detector exceeds a predetermined threshold , the output voltage of the power converter is reduced. Power supply. An input transformer having a plurality of secondary windings is provided on the input side of the power converter,
The power converter is
Each input is connected to the secondary winding, and consists of a plurality of unit inverters that output a single-phase AC voltage having a desired voltage and frequency.
The plurality of unit inverters are divided into three groups, the outputs of each group are connected in series, and one end thereof is connected as a neutral point to obtain a three-phase AC output from the other end. The on-shore power supply device for a ship according to any one of claims 1 to 4 , wherein

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