CN111585309A - Ship shore power bidirectional grid-connected control system - Google Patents

Abstract

The invention discloses a ship shore power bidirectional grid-connected control system, and relates to the technical field of port power supply. The shore power variable-voltage variable-frequency power supply is connected with an electric connection box through a ship shore connection switch and a transformer, and the electric connection box is connected with a first closing switch on the ship side; the ship power generation equipment, the ship power distribution unit and the ship load are connected through a ship power bus, and the ship power generation equipment is connected with the ship power distribution unit through a second closing switch; the intelligent control device is respectively connected with the shore power voltage and frequency conversion power supply and the ship power generation equipment, and comprises a data acquisition module, a control module, a display module and a human-computer interaction module. The invention has the advantages that: the intelligent control device can realize a bidirectional grid-connected function, can meet various different working environments, improves the technical effect of the utilization rate of the shore power, increases the stability of a shore power system, is more convenient and safer, and can reduce the cost.

Description

A two-way grid-connected control system for ship shore power

technical field

The invention relates to the technical field of port power supply, in particular to a two-way grid-connected control system for ship shore power.

Background technique

At the port of call, the power system of the ship is powered by diesel generators, which causes serious environmental pollution. In response to the national policy of energy conservation and emission reduction, the power supply of the ship's generator is cut off during the ship's call at the port, and the power supply is changed to shore power. In special environments such as islands and reefs, offshore work platforms, and the lack of equipment conditions, it is necessary to adjust the output voltage of the ship's generator to synchronize it with the shore power supply. If it is complete, the output voltage of the shore power supply should be adjusted to synchronize with the ship generator to meet the grid-connected operation specifications. In the prior art, the ship's automatic grid-connecting device is usually installed on the ship. When the ship-side generator automatic grid-connecting system fails, the shore power cannot be automatically connected to the grid.

In the prior art, an application number 201820001278.4 is disclosed for a two-way grid-connected system of variable-frequency shore power supply. The frequency converter of the grid-connected system itself has the function of automatic grid-connection, and there is no need to add additional automatic grid-connected devices. After the failure, the automatic grid-connection function of the variable frequency power supply can be used to improve the reliability of the grid-connected system, but it needs to install an automatic grid-connected system for both the ship-side generator and the variable-frequency power supply, which cannot perform unified automatic grid-connection control and cannot meet the various practical applications. Therefore, it is necessary to design a two-way grid-connected control system for shore power system to solve the above problems.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a two-way grid connection control system for ship shore power, which can be applied to various working environments, can perform unified automatic grid connection control, and can avoid the problem that the ship generator fails to be connected to the grid. .

In order to solve the above-mentioned technical problems, the technical scheme of the present invention is: including

A shore power device, the shore power device includes mains, an emergency switch, a shore power variable voltage and variable frequency power supply, a switch at the ship-shore connection, a transformer, and a power connection box, wherein the shore power variable voltage variable frequency power supply includes rectification, filter , the inverter part is connected to the mains through the emergency switch, the output of the shore power variable voltage variable frequency power supply is connected to the connection box after the switch at the ship-shore connection and the transformer, and the connection box is connected to the first closing switch on the ship side ;

A ship power device, the ship power device includes a ship power generation equipment, a ship power distribution unit, a ship load and a second closing switch, the ship power generation equipment, the ship power distribution unit, and the ship load are connected through the ship power bus, and the ship generates power. The equipment is connected to the ship's power distribution unit through the second closing switch;

An intelligent control device respectively connected with the shore power variable frequency variable frequency power supply and the ship's power generation equipment, the intelligent control device includes the shore power variable frequency variable voltage power supply and the ship's power generation equipment, and is used for collecting the shore power variable frequency variable voltage power supply and the ship's voltage , frequency, phase data acquisition module, connected to the data acquisition module and used for the reception and output of data signals to control the shore power variable frequency variable voltage power supply and the control module of the ship power generation equipment, connected with the shore power variable frequency variable voltage power supply and ship power generation equipment And a display module used to display voltage and frequency data, and a human-computer interaction module connected to shore power variable frequency variable voltage power supply and ship power generation equipment and used to send instructions to shore power and ships;

The control module is respectively connected with the shore power variable frequency variable frequency power supply and the ship power generation equipment, and the control module has a speed regulation and excitation control module for the ship power generation equipment and a control algorithm module for the shore power variable frequency variable voltage power supply inverter.

Further, the shore power variable frequency variable voltage power supply is provided with a voltage regulating device and a frequency regulating device.

Further, the marine power generation equipment is a diesel generator set.

Further, the marine power generation equipment is a generator with reverse power protection.

The advantages of the invention are: a two-way grid-connected control system for ship shore power, the intelligent control device is arranged at the shore side wharf to achieve the characteristics of easy maintenance and convenient operation, and at the same time, the intelligent control device can adjust the parameters of the small-capacity system to follow the large-scale capacity system parameters, realize the function of two-way grid connection, conform to the grid-connected operation specifications of the power grid, and can meet a variety of different working environments, which is more reasonable and safer than the existing technology; the above technical means can also achieve mutual redundancy, The technical effect of improving the utilization rate of shore power, increasing the stability of the shore power system, making it more convenient and safe, and reducing costs.

Description of drawings

Fig. 1 is the grid-connected control structure diagram of the ship shore power bidirectional grid-connected control system of the present invention;

Fig. 2 is the speed regulation and virtual speed regulation control diagram of the present invention;

Fig. 3 is the excitation and virtual excitation control diagram of the present invention;

Fig. 4 is the virtual synchronous generator control algorithm diagram of the present invention;

FIG. 5 is a process diagram of the control algorithm switching of the bidirectional grid-connected control system of the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings.

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The following embodiments can make those skilled in the art understand the present invention more comprehensively, but do not limit the present invention to the scope of the described embodiments.

As shown in FIG. 1 , this specific embodiment adopts the following technical solutions: it includes a shore power device, a ship power device, and an intelligent control device 3 . The switch SE2, the transformer 4, and the connection box 6 at the shore connection, wherein the shore power variable voltage variable frequency power supply 2 includes rectification, filtering, and inverter parts and is connected to the mains 1 through the emergency switch SE1, and the shore power variable voltage variable frequency power supply 2 is connected. The output is connected to the connection box 6 after passing through the SE2 switch at the ship-shore connection and the transformer 4, and the connection box 6 is connected to the first closing switch S1 on the ship side;

Ship power device, ship power device includes ship power generation equipment 5, ship power distribution unit 7, ship load and second closing switch S2, ship power generation equipment 5, ship power distribution unit 7, ship load is connected through ship power bus, ship power generation The equipment 5 is connected to the ship power distribution unit 7 through the second closing switch S2;

The intelligent control device 3 is respectively connected with the shore power variable voltage variable frequency power supply 2 and the ship power generation equipment 5, and is used to receive the shore power voltage, frequency and phase from the shore power variable voltage variable frequency power supply 2, and receive the ship voltage, frequency, and phase from the ship power generation equipment 5. phase, and adjust the output of the shore power variable voltage variable frequency power supply 2 or the output of the ship's power generation equipment 5.

The intelligent control device 3 includes a data acquisition module, a control module, a display module, and a human-computer interaction module. The data acquisition module is connected to the shore power variable frequency variable voltage power supply 2 and the ship power generation equipment 5, and is used to collect the converted voltage and the ship voltage, including the voltage of the ship. Phase sequence, amplitude, frequency, and phase difference.

The control module is connected to the data acquisition module, and is used for receiving from the data acquisition module the phase sequence of the converted voltage and the phase sequence of the ship's voltage, the amplitude of the converted voltage and the amplitude of the ship's voltage, the frequency of the converted voltage and the frequency of the ship's voltage, and the phase angle of the converted voltage Compare and judge with the voltage phase angle of the ship to determine whether the grid-connected closing conditions are met, and the control module calculates the control signal according to the grid-connected closing conditions, and sends the adjustment signal to the output of the shore power variable voltage variable frequency power supply 2 or the output of the ship power generation equipment 5 , and realize the start-stop control command to the ship power generation equipment 5. The control module adopts the virtual synchronous generator control method, as shown in Figure 4, to realize the two-way control of the shore power variable frequency variable voltage power supply 2 and the ship power generation equipment 5. Before, it will go through the synchronization module first, and it can be connected to the grid only when the grid connection conditions are met.

The display module is connected to the shore power variable frequency power supply 2 and the ship power generation equipment 5 respectively, and is used to display the real-time voltage of the converted voltage and the ship voltage, and to display whether the shore power variable frequency power supply 2 and the ship power generation equipment 5 are successfully switched.

The human-computer interaction module is connected to the shore power transformation and frequency conversion device 2 and the ship power generation equipment 5, and is used to select the command to connect the shore power or the ship to the grid, so as to complete the one-button grid connection operation control.

When the ship is in port, the data acquisition module can collect the data parameters and equipment conditions of the shore side and the ship side, and determine which side to adjust. If the docking is a normal port and the terminal equipment conditions are sufficient, it can detect the presence of inverters and grid capacity. When the power consumption of the ship is satisfied, the shore side is adjusted; when docking on some islands and reefs, due to the relative lack of shore-side equipment on the islands and reefs, and the inverter cannot be detected, the ship side is adjusted. At the same time, the human-computer interaction module can also be judged manually. , manually set to adjust shore side or ship side.

Mains 1 provides power for the shore power grid-connected system, which is 10kV a.c for the conventional power grid; the right side of the power supply is the emergency switch SE1: emergency disconnection when a fault occurs, to ensure the safety of shore power components and ship power components and equipment; shore power frequency conversion Voltage source 2: Regulate the voltage and frequency of the grid power supply, stabilize the voltage and frequency of the shore power system; Intelligent control device 3: Control the shore power based on the data acquisition module, virtual synchronous generator control module, display module, and human-computer interaction module Two-way grid-connected system regulation control; switch SE2 at the ship-shore connection: when the variable-frequency power supply meets the requirements of grid-connected conditions, the variable-frequency power supply control switch is closed and connected to the grid; Circuit isolation, protecting personal safety and isolating dangerous voltage; the first closing switch S1: the closing switch for shore power supply, connecting the shore power supply and the ship's load; the second closing switch S2: for the power supply of the ship's generator The closing switch is connected to the ship's power supply and the ship's load; the ship's power generation equipment 5: It is a diesel generator set with reverse power protection function.

As shown in Fig. 2-Fig. 5, the control module adopts virtual synchronous generator control. Fig. 2 is the structure diagram of speed regulation and virtual speed regulation control; Fig. 3 is the structure diagram of excitation and virtual excitation control; Fig. 4 is the control algorithm diagram of virtual synchronous generator. According to the different control objects selected, input corresponding parameters to adjust and control.

When the ship is docked on islands and reefs or offshore floating platforms and other special environments, and there is no variable frequency variable voltage power supply equipment on the shore side, adjust the parameters of the ship's generator to synchronize with the power supply of the islands and reefs or offshore working platforms. At this time, the acquisition module collects the ship's power generation Equipment parameter information, the active power P _m of the speed regulation control module adjusts the ship generator, where ω is the output voltage frequency of the ship generator, ω ₀ is the angular frequency of the ship's power system, and P _ref is the ship generator's angular frequency. Output active power given value, P _m is the output active power of the ship generator, K _p is the droop coefficient. The excitation controller adjusts the output voltage of the marine generator, where Q _ref is the reactive power given value of the generator, Q is the reactive power value of the generator, U _ref is the voltage given value, and U is the output of the generator voltage, E is the output voltage value, D _q is the reactive power adjustment coefficient, and _Ku is the voltage adjustment coefficient.

When the ship docks at the coastal wharf, inland wharf, etc., the shore side is equipped with variable frequency variable voltage power supply equipment, which can adjust the output voltage of the shore power supply to synchronize it with the ship's generator. At this time, the acquisition module collects the parameter information of the shore power supply, and the virtual speed regulation control module outputs the active power P _m to adjust the virtual synchronous generator, where ω is the voltage frequency of the output terminal of the shore power supply, and ω ₀ is the three-phase mains power The angular frequency of the power grid, P _ref is the given value of the output active power of the shore power supply, P _m is the virtual output active power, and K _p is the droop coefficient. The virtual excitation controller adjusts the output voltage of the shore power supply, where Q _ref is the given value of the output reactive power of the shore power supply, Q is the reactive power value of the variable frequency power supply, U _ref is the given value of the voltage, and U is the given value of the power supply. Output voltage, E is the output voltage value, D _q is the reactive power adjustment coefficient, and _Ku is the voltage adjustment coefficient. Bring the above P _m into the virtual rotor shaft part of the virtual synchronous generator algorithm to obtain the phase angle θ, as shown in Figure 4; the above E and θ input voltage synthesis module synthesizes the reference value voltage U ₁ . The obtained voltage U ₁ is used as the input value generated by SPWM to complete the control of the variable frequency power supply, where P _e is the electromagnetic power, J is the moment of inertia, and D is the constant damping coefficient.

Through the human-computer interaction module, the command of grid connection is sent to the shore power or the ship, and each switch is closed to complete the one-button grid connection operation control and complete the grid connection.

In this specific embodiment, the intelligent control device is arranged on the shore-side wharf to achieve the characteristics of easy maintenance and convenient operation. At the same time, the intelligent control device can not only realize the function of two-way grid connection, but also meet a variety of different working environments and increase the shore power system. Stability, more convenience and safety, and can reduce costs.

The foregoing has shown and described the basic principles and main features of the present invention, as well as the advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above-mentioned embodiments, and the descriptions in the above-mentioned embodiments and the description are only to illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have Various changes and modifications fall within the scope of the claimed invention. The claimed scope of the present invention is defined by the appended claims and their equivalents.

Claims (4)

1. a ship shore power two-way grid-connected control system is characterized in that: comprising: A shore power device, the shore power device includes mains, an emergency switch, a shore power variable voltage and variable frequency power supply, a switch at the ship-shore connection, a transformer, and a power connection box, wherein the shore power variable voltage variable frequency power supply includes rectification, filter , the inverter part is connected to the mains through the emergency switch, the output of the shore power variable voltage variable frequency power supply is connected to the connection box after the switch at the ship-shore connection and the transformer, and the connection box is connected to the first closing switch on the ship side ; A ship power device, the ship power device includes a ship power generation equipment, a ship power distribution unit, a ship load and a second closing switch, the ship power generation equipment, the ship power distribution unit, and the ship load are connected through the ship power bus, and the ship generates power. The equipment is connected to the ship's power distribution unit through the second closing switch; An intelligent control device respectively connected with the shore power variable frequency variable frequency power supply and the ship's power generation equipment, the intelligent control device includes the shore power variable frequency variable voltage power supply and the ship's power generation equipment, and is used for collecting the shore power variable frequency variable voltage power supply and the ship's voltage , frequency, phase data acquisition module, connected to the data acquisition module and used for the reception and output of data signals to control the shore power variable frequency variable voltage power supply and the control module of the ship power generation equipment, connected with the shore power variable frequency variable voltage power supply and ship power generation equipment And a display module used to display voltage and frequency data, and a human-computer interaction module connected to shore power variable frequency variable voltage power supply and ship power generation equipment and used to send instructions to shore power and ships; The control module is respectively connected with the shore power variable frequency variable frequency power supply and the ship power generation equipment, and the control module has a speed regulation and excitation control module for the ship power generation equipment and a control algorithm module for the shore power variable frequency variable voltage power supply inverter. 2 . The two-way grid-connected control system for ship shore power according to claim 1 , wherein the shore power variable frequency variable voltage power supply is provided with a voltage regulating device and a frequency regulating device. 3 . 3 . The two-way grid-connected control system for ship shore power according to claim 1 , wherein the ship power generation equipment is a diesel generator set. 4 . 4 . The two-way grid-connected control system for ship shore power according to claim 1 , wherein the ship power generation equipment is a generator with reverse power protection. 5 .

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