JP6898796B2 - Monitoring system - Google Patents

Description

The present invention relates to a monitoring system that monitors a propulsion system of an electric propulsion vessel.

In recent years, an electric propulsion ship that rotates a propeller for propulsion by an electric motor has been put into practical use. Patent Document 1 discloses an electric propulsion vessel that generates electric power by driving a generator with a prime mover and drives an electric motor connected to a propeller with the generated electric power.

Japanese Unexamined Patent Publication No. 2015-12883

The propulsion system of an electric propulsion vessel is different from a propulsion system in which a propeller is directly rotated by a prime mover, and many devices including electric devices are provided between the prime mover and the propeller. In the past, it was thought that electrical equipment without moving parts would hardly deteriorate, and since it is not always easy to attach sensors to all equipment, the propulsion system of an electric propulsion ship monitors each equipment individually. Nothing has been done.

However, electrical equipment mounted on ships may deteriorate due to the influence of ambient temperature and vibration, and even if sensors cannot be attached to all equipment, it is a major cause of deterioration of the propulsion system. There is also a request to identify the device to be used.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an effective monitoring system for identifying equipment that is a main cause of deterioration in a propulsion system of an electric propulsion vessel. ..

The monitoring system according to one aspect of the present invention is a monitoring system that monitors the propulsion system of an electric propulsion ship, and includes a processing device having a processor and a display, and the processing device is one or more in the propulsion system. The input value and output value of each section divided so as to include a plurality of devices are acquired, the section efficiency in each section is calculated based on the input value and the output value, and the output value and the reference efficiency stored in advance are used. The reference efficiency corresponding to the acquired output value is calculated based on the relationship of the above, and the efficiency deviation obtained by subtracting the reference efficiency from the section efficiency is displayed on the display in chronological order for each section.

According to this configuration, the efficiency deviation of each section is displayed on the display in chronological order, so that the degree of deterioration can be grasped for each section. Therefore, it is possible to obtain useful information for identifying the equipment that is the main cause of deterioration in the propulsion system. Furthermore, since the efficiency deviation is calculated for each section instead of calculating the efficiency deviation for each device, even if sensors cannot be installed in all devices, the device that is the main cause of deterioration can be identified. You can get useful information to do.

In the above monitoring system, the processing apparatus may display a prediction trend line of the efficiency deviation in each section on the display based on the efficiency deviation in each section.

According to this configuration, since the prediction tendency line of the efficiency deviation is displayed on the display, the efficiency deviation of each section after a predetermined period can be estimated, and information useful for the operation plan such as the replacement time of each device can be obtained. ..

In the above monitoring system, the processing apparatus may display a predetermined warning on the display when the efficiency deviation in each section is below a preset lower limit.

According to this configuration, when the equipment included in each section deteriorates or breaks down, a warning is displayed on the display, which is very effective for the operation of the propulsion system.

In the above monitoring system, the processing apparatus compares the efficiency deviations of sections having the same function and arranged in parallel with each other, and issues a predetermined warning when the difference in the compared efficiency deviations is larger than a preset tolerance. It may be displayed on the display.

According to this configuration, deterioration or failure of each section can be grasped by comparing the efficiency deviations of sections having the same function and arranged in parallel with each other.

According to the above-mentioned monitoring system, it is possible to provide useful information for identifying the equipment that is the main cause of deterioration in the propulsion system of the electric propulsion ship.

FIG. 1 is a block diagram of a propulsion system for an electric propulsion vessel. FIG. 2 is a block diagram of the monitoring system. FIG. 3 is a flowchart of the monitoring program. FIG. 4 is a diagram showing an example of a scatter plot and an efficiency curve displayed on a display. FIG. 5 is a diagram showing the efficiency deviation displayed on the display in chronological order and an example of a prediction trend line.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following, the same or corresponding elements will be designated by the same reference numerals throughout the drawings, and duplicate description will be omitted.

<Propulsion system>
First, the propulsion system 101, which is the monitoring target of the monitoring system 100 according to the present embodiment, will be described. FIG. 1 is a block diagram of the propulsion system 101. The propulsion system 101 of the present embodiment is mounted on an electric propulsion ship, and is a two-axis propulsion system in which two propellers 17 are rotated by a plurality of prime movers 10. More specifically, the propulsion system 101 of the present embodiment includes four prime movers 10, four generators 11, one main switchboard 12, four transformers 13, two inverters 14, and two. It includes an electric motor 15, two speed reducers 16, and two propellers 17. The number of each device is not limited to the above. For example, the number of propellers 17 may be one.

The prime mover 10 is a device that generates power by burning fuel inside. The prime mover 10 of the present embodiment is a diesel engine, but may be another engine such as a gas turbine engine. Further, a flow meter 31 is provided in the fuel line for supplying fuel to the prime mover 10. The flow meter 31 can measure the fuel flow rate, that is, the fuel consumption in the prime mover 10. If the fuel consumption is known, the thermal energy [J (joule)] generated when the fuel burns in the prime mover 10 can be calculated, and by extension, the thermal energy per second [J / s = W] supplied to the prime mover 10 can be calculated. (Watts)] can be calculated. That is, the input value [W] to the prime mover 1 can be measured from the measurement result of the flow meter 31.

The generator 11 is a device that is driven by the prime mover 10 to generate electric power. The generator 11 of the present embodiment is an AC generator that generates AC power. Further, the electric power generated by the generator 11 is supplied to the main switchboard 12 via a circuit. A power meter 32 is provided in the circuit connecting the generator 11 and the main switchboard 12, and the power meter 32 measures the electric power (output value of the generator 11) [W] supplied by the generator 11 to the main switchboard 12. be able to.

The main switchboard 12 is a device that once collects the electric power supplied from the four generators 11 and distributes it to the four transformers 13. A power meter 33 is provided in each circuit connecting the main switchboard 12 and the transformer 13, and the power meter 33 measures the power (input value of the transformer 13) [W] supplied to each transformer 13. Can be done.

The transformer 13 is a device that converts the voltage of the electric power supplied from the main switchboard 12.

The inverter 14 is a device that changes the frequency of AC power. The inverter 14 converts the AC power supplied from the transformer 13 into DC power, and further converts the converted DC power into AC power. Further, the electric power whose frequency has been changed by the inverter 14 is supplied to the motor 15 via a circuit. A power meter 34 is provided in the circuit connecting the inverter 14 and the electric motor 15, and the power meter 34 can measure the electric power (output value of the inverter 14) [W] supplied from the inverter 14 to the electric motor 15. The electric power supplied from the inverter 14 to the electric motor 15 is equal to the electric power (input value of the electric motor 15) [W] supplied to the electric motor 15.

The electric motor 15 is a device that rotates the output shaft by the electric power supplied from the inverter 14. The output shaft of the electric motor 15 is provided with a tachometer 35 for measuring the rotation speed of the output shaft and a torque meter 36 for measuring the torque applied to the output shaft. The output (output value) [W] of the electric motor 15 can be calculated based on the measurement results of the tachometer 35 and the torque meter 36. The output value of the motor 15 is equal to the input value [W] of the speed reducer 16.

The speed reducer 16 is a device that reduces the rotational speed and transmits the power of the rotational movement by the output shaft of the electric motor 15 to the propeller 17. The speed reducer 16 and the propeller 17 are connected to each other via a propulsion shaft, and the propulsion shaft is provided with a tachometer 37 for measuring the rotation speed of the propulsion shaft and a torque meter 38 for measuring the torque applied to the propulsion shaft. The output (output value) [W] of the speed reducer 16 can be calculated based on the measurement results of the tachometer 37 and the torque meter 38.

The propeller 17 rotates in water to generate propulsive force for the ship. The propeller 17 is driven by a propulsion shaft connected to the speed reducer 16. The propeller 17 has a plurality of rotor blades, and these rotor blades have a constant angle (pitch). However, the propeller 17 may be a variable pitch propeller in which the angle of the rotary blade can be arbitrarily changed.

<Monitoring system>
Next, the configuration of the monitoring system 100 will be described. FIG. 2 is a block diagram of the monitoring system 100. As shown in FIG. 2, the monitoring system 100 includes a processing device 51 and a display 52. In the present embodiment, the processing device 51 and the display 52 are installed on land, but the processing device 51 and the display 52 may be installed on the ship, and a part of the processing device 51 is installed on the ship and the processing device 51 is installed. The remaining part of the display 52 and the display 52 may be installed on land.

The processing device 51 includes a processor, a volatile memory, a non-volatile memory, an I / O interface, and the like. As shown in FIG. 2, the measurement data of the various sensors 31 to 38 (see FIG. 1) are supplied to and stored in the server 53 installed on land via a satellite. The processing device 51 acquires measurement data of various sensors 31 to 38 from the server 53 via a network. The various sensors 31 to 38 perform measurement every 4 hours, for example, and supply the measurement data to the server 53. Further, the processing device 51 is electrically connected to the display 52, and by transmitting an image signal to the display 52, any display content can be displayed on the display 52.

<Monitoring program>
Next, the monitoring program executed by the processing device 51 will be described. In the processing device 51, a monitoring program and various data (including map data described later) are stored in the non-volatile memory, and the processor performs arithmetic processing using the volatile memory based on the monitoring program.

Here, in the present embodiment, the propulsion system 101 to be monitored is divided into four types of sections. Specifically, as shown in FIG. 1, it includes four first sections 41 including a prime mover 10 and a generator 11, two second sections 42 including two transformers 13 and an inverter 14, and an electric motor 15. The propulsion system 101 is divided into four types, two third sections 43 and two fourth sections 44 including the speed reducer 16. The division of the propulsion system 101 is not limited to the above, and may be divided into sections other than the above.

As mentioned above, each section 41-44 includes one or more devices. In addition, similar sections have the same functionality because they contain the same equipment and are arranged in parallel with each other.

FIG. 3 is a flowchart of the monitoring program. The process shown in FIG. 3 is performed by the processing device 51. First, when the processing is started, the processing device 51 acquires the measurement data measured by the various sensors 31 to 38 from the server 53 (step S1). In this embodiment, all the measurement data including the measurement data accumulated in the server 53 in the past are acquired. Further, the operations of steps S2 to S5, which will be described later, are also performed on the past measurement data. However, the user may specify a period for analysis, acquire measurement data in that period, and perform an operation on the acquired measurement data.

Subsequently, the processing device 51 calculates the input value and the output value of each section based on the measurement data acquired in step S1 (step S2). In the first section 41, the thermal energy per unit time supplied to the prime mover 10 is defined as an “input value”, and the electric power supplied by the generator 11 to the main switchboard 12 is defined as an “output value”. In the second section 42, the electric power supplied to the two transformers 13 is referred to as an “input value”, and the electric power supplied by the inverter 14 to the motor 15 is referred to as an “output value”. In the third section 43, the electric power supplied to the motor 15 is referred to as an “input value”, and the power transmitted from the motor 15 to the speed reducer 16 is referred to as an “output value”. In the fourth section 44, the power transmitted from the motor 15 to the speed reducer 16 is referred to as an “input value”, and the power transmitted from the speed reducer 16 to the propeller 17 is referred to as an “output value”.

Subsequently, the processing device 51 calculates the section efficiency in each section based on the ratio of the output value to the input value in each section (step S3). In the present embodiment, the section efficiency of each section is the value obtained by dividing the output value by the input value in each section. If the units of the input value and the output value are different, convert one and match both units before calculating the section efficiency.

Subsequently, the processing device 51 calculates the reference efficiency (step S4). Specifically, the processing device 51 stores the map data of the reference efficiency curve for each section, and calculates the reference efficiency corresponding to the output value calculated in step S2 based on the map data. The reference efficiency curve is a curve showing the relationship between the output value expected when the equipment included in the section is not deteriorated and the section efficiency (reference efficiency). Further, the reference efficiency curve can be obtained based on, for example, the design value of the equipment included in the section, the test result at the time of manufacture, or the sea trial run result.

Subsequently, the processing device 51 calculates the efficiency deviation for each section (step S5). The efficiency deviation is the section efficiency minus the reference efficiency. That is, the efficiency deviation is a value indicating the degree of decrease in efficiency from the reference efficiency (how much the efficiency has decreased due to deterioration).

Subsequently, as shown in FIG. 4, the processing device 51 displays a scatter diagram plotting the points corresponding to the output value (load) and the section efficiency on the display 52 for each section, and superimposes the scatter diagram on the scatter diagram. In this way, the reference efficiency curve described above is displayed on the display 52 (step S6).

Note that FIG. 4 is an example of a scatter plot and a reference efficiency curve displayed on the display 52. In addition, the scatter plot and the reference efficiency curve are displayed for each section. The unit on the horizontal axis of the scatter plot may be the unit of the output value [W], or may be the maximum output or the ratio [%] to the rated capacity. Further, the unit of the vertical axis of the scatter plot may be the efficiency [%], or may be the value before multiplying the efficiency by 100 (the value obtained by dividing the output value by the input value). In addition, the reference efficiency curve naturally differs depending on the type of section. Furthermore, even if the sections are of the same type, the reference efficiency curve may differ if there are individual differences in the equipment included.

Subsequently, as shown in FIG. 5, the processing device 51 displays a diagram in which the efficiency deviation is plotted in time series for each section on the display 52, and superimposes the diagram on the efficiency deviation prediction trend line. Display on the display (step S7). The prediction tendency line is an approximate curve drawn so that the distance from each point of the efficiency deviation plotted in time series is small, and may be a straight line or a curve. The method for calculating the approximate curve is not particularly limited, and the approximate curve may be calculated using the least squares method or the Kalman filter.

FIG. 5 is an example of a diagram showing the efficiency deviation displayed on the display 52 in chronological order and a prediction trend line. The efficiency deviation of each section is superimposed and displayed in chronological order. As a result, the tendency of efficiency decrease in each section can be grasped, and it is effective in identifying the device that is the main cause of deterioration in the propulsion system 101. In addition, by displaying the prediction trend line, it is possible to predict the degree of decrease in efficiency of each section after a predetermined period. The broken line in the graph of FIG. 5 is a straight line having an efficiency deviation of zero. As the equipment deteriorates, the efficiency deviation of the section containing the equipment decreases, and the negative range of the efficiency deviation increases.

Subsequently, the processing device 51 determines whether or not the efficiency deviation is equal to or greater than a preset lower limit value (step S8). If all the efficiency deviations calculated in step S5 (or the latest efficiency deviations) are equal to or greater than the lower limit (YES in step S8), the process proceeds to step S9.

On the other hand, if any of the efficiency deviations calculated in step S5 is smaller than the lower limit value (below the lower limit value) (or if the latest efficiency deviation is smaller than the lower limit value) (NO in step S8), the display 52 determines. Warning is displayed (step S10). For example, the background color of the display part of the corresponding section may be changed, or each section may be numbered to display the number of the corresponding section. After passing through step S10, the process ends.

Subsequently, in step S9, the latest section efficiencies are compared for the same type of sections having the same function and arranged in parallel with each other, and it is determined whether or not the difference in section efficiencies is within a preset tolerance. If the difference in section efficiency is within the tolerance (YES in step S9), the process ends.

On the other hand, if the difference in section efficiency is larger than the tolerance (NO in step S9), a predetermined warning is displayed on the display 52 (step S10). Since there are four sections 41 in the first section, if the section efficiencies of all the first sections are compared and even one difference in section efficiency is larger than the tolerance, the process proceeds to step S10. However, regarding the first section 41, when even one of the four section efficiencies is larger than the tolerance with respect to the average value, or when the difference between the maximum value and the minimum value of the four section efficiencies is larger than the tolerance. May proceed to step S10. After passing through step S10, the process ends.

In the step of detecting deterioration or abnormality by comparing the section efficiencies of the same type as in step S9, it is easy to grasp the abnormality of deterioration. Therefore, the above step S9 is particularly effective for the second section 42 including the electric equipment (transformer 13 and inverter 14) which is considered to have little deterioration.

As described above, according to the monitoring system 100 according to the present embodiment, the efficiency deviation for each section including one or more devices is displayed on the display 52 in chronological order, so that the degree of deterioration for each section can be grasped. .. Therefore, it is possible to obtain useful information for identifying the device that is the main cause of deterioration in the propulsion system 101. If a section that is the main cause of deterioration in the propulsion system 101 can be identified, the propulsion system 101 can be operated efficiently by reducing the burden ratio of the section.

In the above embodiment, the case where the processing device 51 is connected to the server 53 via a network has been described, but the server 53 may form a part of the processing device 51. For example, the server may execute the above-mentioned monitoring program to display the figures shown in FIGS. 4 and 5 on the display of the user's PC connected via the network.

10 Motor 11 Generator 12 Main switchboard 13 Transformer 14 Inverter 15 Motor 16 Reducer 41 1st section 42 2nd section 43 3rd section 44 4th section 51 Processing device 52 Display 100 Monitoring system 101 Propulsion system

Claims (4)

A monitoring system that monitors the propulsion system of an electric propulsion ship.
A processing device having a processor, a display, and the like.
The processing device acquires the input value and the output value of each section divided so as to include one or more devices in the propulsion system, and calculates the section efficiency in each section based on the input value and the output value. Then, the reference efficiency corresponding to the acquired output value is calculated based on the relationship between the output value stored in advance and the reference efficiency, and the efficiency deviation obtained by subtracting the reference efficiency from the section efficiency is calculated in chronological order for each section. A monitoring system that is displayed on the display. The monitoring system according to claim 1, wherein the processing apparatus displays a prediction trend line of the efficiency deviation in each section on the display based on the efficiency deviation in each section. The monitoring system according to claim 1 or 2, wherein the processing device displays a predetermined warning on the display when the efficiency deviation in each section falls below a preset lower limit. The processing apparatus compares the efficiency deviations of sections having the same function and arranged in parallel with each other, and displays a predetermined warning on the display when the difference in the contrasted efficiency deviations is larger than a preset tolerance. The monitoring system according to any one of claims 1 to 3.

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