CN101710712B - Automatic recovery method for power loss of shipping grid - Google Patents

Abstract

The invention discloses a method for automatically recovering from power failure of a ship power grid. The process is that when the power grid loses power, a plurality of generating sets compete to start, and any generating set issues a switch-on command and sends an interlocking signal to other generating sets after starting, wherein , when any unit sends a closing command, it determines whether to execute the closing command according to whether it receives the interlock signal sent by other units, and executes the combined brake command of the unit when it does not receive the interlock signal sent by other units. When the interlock signal from other units is received, cancel the combination switch command of this equipment and reissue the switch-on command according to the priority order of the unit and the unit that sent the interlock signal. The ship power grid power failure automatic recovery method ensures the rapidity of ship power grid power loss processing, and solves the problem of simultaneous switching on of multiple generating units, ensuring the uniqueness and on-demand of the switching on power generating units.

Description

Automatic recovery method for ship power grid failure

technical field

The invention belongs to the technical field of ship power systems, and in particular relates to a power failure recovery method for a ship power grid.

Background technique

The ship power system can be divided into four parts: power generation, transmission, distribution and load. The power generation part is mainly to provide electric energy for the ship. It is usually composed of the main power station, emergency power station (used on civilian ships), battery (optional) and shore power ( used when docking) composition. When the ship is sailing normally, the main power station supplies power to each electrical equipment. When the main power station fails and the main busbar loses power, the main switchboard sends a power failure signal to the emergency switchboard, starts the emergency power station, and supplies power to the emergency load. powered by. When the ship is docked, the shore power supplies power to the ship's load.

When the main power station is supplying power to the grid, when the on-grid unit has a serious failure and stops in an emergency, the grid voltage will drop rapidly and tend to lose power. The device is functioning normally.

At present, some mature ship power management system products have the function of automatic recovery after power failure, and there are three main methods of automatic recovery after power failure:

The first type, when the grid loses power, the standby unit with high priority starts to close and supplies power to the grid;

The second type, when the grid loses power, start multiple standby units, and the standby units with high priority combine to supply power to the grid;

The third type, when the power grid loses power, start multiple standby units, and the one that starts successfully first closes the switch, and the other units are blocked by software.

The disadvantage of the first method is that the rapidity of power supply recovery of the ship power grid cannot be guaranteed. The second and third methods have improved the reliability of the rapid recovery of power grid failure to a certain extent, but still cannot guarantee the power supply recovery in the shortest time. In addition, The third method does not consider how to adjust the closing sequence when multiple units send interlock signals at the same time. At the same time, this method may not be able to achieve reliable locking when multiple standby units send interlock signals at the same time.

Contents of the invention

The technical problem to be solved by the present invention is to provide an automatic recovery method for ship power grid failure. The uniqueness and on-demand of the network group.

In order to solve the problems of the technologies described above, the present invention adopts the following technical solutions:

A method for automatically recovering from power failure of a ship power grid. The process is that when the power grid loses power, multiple units compete to start, and after any unit starts, it will issue a closing command and an interlock signal to other units. It is characterized in that: When a unit sends out a closing command, it determines whether to execute the closing command according to whether it receives the interlock signal sent by other units. When the interlock signal sent by other units is received, the combination switch command of the unit is canceled and the closing command is reissued according to the priority order of the unit and the unit that issued the interlock signal.

By adopting the above-mentioned technical scheme, the method for automatically recovering from power failure of the ship power grid of the present invention first causes all units to compete to start when the power grid loses power. The interlock signal sent by the unit is used to determine whether to execute the closing command to ensure the uniqueness and responsiveness of the closing switch unit.

Description of drawings

The present invention is described in detail below in conjunction with accompanying drawing and specific embodiment:

Figure 1 is a structural diagram of the ship power station system.

Fig. 2 is a flow chart of a method for automatically recovering from a power failure in a transmission grid.

Fig. 3 is the chain logic circuit adopted by the controller of the present invention.

Detailed ways

As shown in Figure 1, this is the circuit structure diagram of the ship power station system. In this embodiment, 4 generating units (units No. 1, No. 2, No. 3 and No. 4 respectively) are used. Each unit is composed of a controller 101, a main switch 102 and a generator 103. One end of the main switch 102 is connected to the grid bus bar 200, and the other end is connected to the generator 103; the controller 101 has a grid voltage input terminal, a closing instruction output terminal, One interlock signal output terminal and three interlock signal input terminals, the closing command output terminal is connected to the main switch 102, and the interlock signal output terminal is connected to the interlock signal input terminals of other units.

As shown in Figure 2, once the controller 101 in each unit detects that the power grid is out of power, it sends a start command to the generator 103 in the unit. After the generator 103 starts successfully, the controller 101 reads the voltage U of the unit, Grid voltage Um, rated voltage Ue, rated frequency fe, frequency f of the unit. When U>85%Ue, f=fe, the startup is successful; otherwise, the startup is unsuccessful, and the startup command is sent again. If the startup is not successful after sending 3 times, then the fault alarm is processed.

After the unit starts successfully, read the grid voltage again. If the grid is not in a state of power failure (that is, other units have successfully supplied power to the grid), the process ends; if the power grid is still in a state of The other units send out interlock signals, and then read the interlock status (that is, the unit sends the closing command and receives the interlock signals from other units). If there is no interlock state, the closing signal is output, the closing command is executed, the main switch is closed, and then the status of the main switch is read. If the main switch is closed successfully, the process ends. If the main switch is not closed successfully, Then perform troubleshooting (alarm, rewrite unit status).

If there is an interlocking state, the unit cancels the closing command, then reads the interlocking signals output by other units, determines the sequence number of other units that issued the closing command according to the input port number, and then re-issues the closing command according to the priority order of each closing unit. If the unit is at the highest level, it will re-judge the power failure state of the power grid and issue a closing command, while other units will be delayed.

Among them, the serial number of each unit that issues the closing command at the same time is determined by the following steps:

1. Determine the unit number corresponding to each controller;

2. Connect the interlock signal lines of other unit controllers according to the order of unit numbers from small to large;

3. Determine the unit number corresponding to each interlock signal input terminal according to the set serial number of the unit. For example, the serial number of the unit is 2, and the program defaults that the corresponding sequence of the interlock signal input port is 1, 3, 4;

4. Read the value of each interlock input signal to determine the unit number corresponding to the effective interlock.

As shown in Fig. 3, this is the logic circuit adopted by the unit controller of the present invention. In this interlock logic circuit, the power grid power failure signal input terminal D1 is connected to an input terminal of the AND gate B2 and is connected to an input terminal of the AND gate B1 through the NOT gate A1, and the closing instruction input terminal D2 is respectively connected to the other input terminal of the AND gate B1. One input terminal is connected to the other input terminal of the AND gate B2, and the output terminal of the AND gate B1 is connected to an input terminal of the OR gate E1; the output terminal of the AND gate B2 is connected to the input terminal of the NOT gate A2, and the output terminal of the NOT gate A2 is all the way Connect the interlock signal output terminal D3, and the other channel through the NOT gate A3 is respectively connected to an input terminal of the AND gate B3 and an input terminal of the XOR gate C1, and the other input terminal of the AND gate B3 is connected to the first interlock signal input terminal D4 , the two input terminals of the AND gate B4 are respectively connected to the second interlock signal input terminal D5 and the third interlock signal input terminal D6; the output terminals of the AND gate B3 and the AND gate B4 are respectively connected to the two input terminals of the AND gate B5, The output end of the AND gate B5 is respectively connected to the other input end of the OR gate E1 and the other input end of the exclusive OR gate C1; the output end of the exclusive OR gate C1 is connected to the interlock status flag D7; the output end of the OR gate E1 is connected to Closing relay J.

Among them, the three interlock signal input terminals D4, D5 and D6 are the interlock input of the interlock signal sent by other unit controllers to the local machine; the interlock signal output terminal D3 of the local machine interlock signal is sent to other unit controllers. Interlock output; one XOR output to the interlock status flag of this controller, which is used to judge the control process. The XOR logic input status is described as follows:

00——The machine has not issued a closing command

11——Local closing

10——Multiple machines issue a closing command

01 - invalid state

The XOR logic output state is described as follows:

0—consistent with the closing command

1——closing command conflict

As shown in Figure 1, taking the controller of No. 1 unit as an example, when the grid has power, the closing command of the controller is directly output through the upper circuit to drive the main switch to close; when the grid fails, the controller The closing command issued can only be output after the judgment of the interlock circuit. When No. 1 controller issues a closing command, the closing signal is combined with the interlocking signals of other units. If no other controller issues a closing command, the logic output is "1", and the closing signal is output to drive the main switch to close. If there are other controllers that issue a closing command, the logic output will be "0", and the closing signal will not be output temporarily, and the information will be transmitted to the control program by the interlock status flag, and the closing command will be redistributed according to the starting sequence of each unit .

This circuit has a simple structure, high real-time performance, one-to-one correspondence between the output and the physical state, and will not cause differences in logic judgment.

However, those skilled in the art should recognize that the above-mentioned specific implementation is only exemplary, for better understanding of the patent for those skilled in the art, and should not be understood as limiting the scope of the patent, as long as it is based on this Any equivalent change or modification of the spirit disclosed in the patent falls within the scope of this patent.

Claims (2)

1. A method for automatic restoration of ship power grid failure, the process of which is that when the power grid loses power, multiple units compete to start, and after any unit starts, it sends a closing command and sends an interlock signal to other units. When the closing command is issued, it is determined whether to execute the closing command according to whether it receives the interlocking signal sent by other units, and when the interlocking signal sent by other units is not received, the combined switching command of the machine is executed, which is characterized in that: When the interlock signal from other units is received, the combination switch command of the unit is canceled and the closing command is reissued according to the priority order of the unit and the unit that issued the interlock signal. 2. The method for automatically recovering from power failure of the ship power grid according to claim 1, characterized in that: the unit that should first issue the closing command according to the priority order needs to judge whether the power grid is out of power again before sending the closing command, such as If there is a power failure, a switch-on command will be issued, otherwise the recovery process will end.

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