JP6047923B2 - Variable pitch propeller control device, ship equipped with variable pitch propeller control device, and variable pitch propeller control method - Google Patents

Description

  The present invention is equipped with a variable pitch propeller control device capable of suppressing problems caused by response delay in CPP blade angle control in a ship equipped with a variable pitch propeller (hereinafter referred to as CPP as appropriate). The present invention relates to a ship and a variable pitch propeller control method.

In Patent Document 1, for the purpose of reducing the amount of smoke generated when the load or output of an engine is increased, (1) the pitch of the propeller is first reduced under a constant output, and the engine and variable Increase the rotation speed of the pitch propeller. (2) Next, increase the engine output and increase the propeller pitch to maintain a substantially constant rotation speed. (3) Propeller efficiency increases the engine output. The variable pitch propeller and the fuel injection control method for the diesel engine are described in which the operation is increased until reaching the optimum value, and (4) the operations of (1) to (3) are repeated according to the necessity of increasing the output.
Patent Document 2 describes a configuration in which the governor control, the propeller pitch control means, and the like are comprehensively controlled in the marine vessel propulsion device so that the fuel consumption efficiency of the main engine can be kept optimal.
Patent Document 3 discloses a propeller inflow speed grasping means and a rotation of the main engine for the purpose of improving the fuel consumption by operating the main engine at a highly efficient rotational speed in accordance with fluctuations in the propeller inflow speed due to the influence of waves and the like A rotation speed control means for controlling the number of rotations, and a correction means for correcting the target rotation speed in accordance with fluctuations in the propeller inflow speed. The correction means is efficient on the efficiency diagram with respect to fluctuations in the propeller inflow speed. There is described a marine engine control system that corrects a target rotational speed by moving a control point along a path that does not decrease.
Patent Document 4 discloses control means for controlling the main engine in a plurality of control modes for the purpose of performing governor control in accordance with sea conditions and suppressing fuel consumption of the main engine, and detecting a control amount in the control of the main engine. And a mode selection means for selecting a control mode on the basis of the detected control amount and the amount of change in the control amount estimated using ship speed and wave information in the voyage area. Main engine control system is described.

JP 7-149287 A JP-A-8-239093 JP 2010-236463 A JP 2011-214471 A

In the CPP blade angle control of a ship equipped with a variable pitch propeller, there is a response delay with respect to a command value although there is a difference in degree depending on the drive system. Therefore, in order to improve the accuracy and make the propulsion system follow the load fluctuation caused by the waves, it is preferable to control the CPP blade angle in consideration of this response delay. However, any of the inventions described in Patent Documents 1 to 4 uses the latest measurement data as an input value, and does not consider any response delay of the CPP blade angle.
Therefore, the present invention is based on the reduction of main engine troubles by suppressing load fluctuations in waves, optimum control theory, etc. by taking into account the response delay to the command value in driving the CPP blade angle in CPP blade angle control. An object of the present invention is to provide a variable pitch propeller control device, a ship equipped with the device, and a variable pitch propeller control method capable of realizing energy consumption suppression and the like.

A variable pitch propeller control device according to a first aspect of the present invention includes a main engine as a prime mover for driving a hull, a variable pitch propeller driven by the main engine via a drive shaft, and operating conditions of the variable pitch propeller. The operation condition setting means to be set, and the predicted destination time set in consideration of the time delay of the drive system of the variable pitch propeller based on the real time inflow speed obtained in real time for the inflow speed of water to the variable pitch propeller A propeller inflow speed predicting means for predicting the predicted inflow speed in the engine, and a control for controlling the variable pitch propeller on the basis of the operating conditions set by the operating condition setting means and the predicted inflow speed predicted by the propeller inflow speed predicting means. Means are provided.
With the above configuration, it is possible to control the variable pitch propeller using the prediction result by the propeller inflow velocity prediction means, and to suppress the influence due to the response delay in the CPP blade angle control of the variable pitch propeller.

The present invention described in claim 2 is the variable-pitch propeller control system as claimed in claim 1, wherein the prediction of the predicted inflow rate by the propeller inflow velocity predicting means, provided for measuring the inflow rate in real time The prediction is based on the measurement result of the real-time measurement means.
With the above configuration, it is possible to perform control in consideration of the response delay of the variable pitch propeller, using the inflow velocity predicted based on the measurement result obtained by the real-time measurement means.

According to a third aspect of the present invention, in the variable pitch propeller control device according to the second aspect, the real-time measuring means is a shaft horsepower meter capable of measuring the torque of the drive shaft.
According to a fourth aspect of the present invention, in the variable pitch propeller control device according to the second aspect, the real-time measuring means is a shaft horsepower meter capable of measuring the thrust of the drive shaft.
With the above configuration, the inflow speed can be predicted based on the measurement result obtained by the torque measurement of the drive shaft and the real time measurement of the thrust (thrust) measurement by the shaft horsepower meter.

According to a fifth aspect of the present invention, in the variable pitch propeller control device according to the third or fourth aspect, in the prediction of the predicted inflow speed, the independent performance curve of the variable pitch propeller and the rotational speed of the main engine The pitch angle of the variable pitch propeller is used.
With the above configuration, the inflow speed of water to the variable pitch propeller can be easily predicted using the single performance curve of the variable pitch propeller, the rotation speed and the pitch angle of the main engine.

According to a sixth aspect of the present invention, in the variable pitch propeller control device according to the second aspect, the hull further includes a relative water level measuring means and / or an incident wave measuring means and a hull motion measuring means, and the predicted inflow velocity. In the prediction, the relative water level measurement means and / or the measurement results of the incident wave measurement means and the hull motion measurement means are used.
With the above configuration, it is possible to obtain information on fluctuations in the propeller inflow speed from the waves measured by the relative water level measuring means and / or the incident wave measuring means and the hull motion measured by the hull motion measuring means.

According to a seventh aspect of the present invention, in the variable pitch propeller control device according to one of the first to sixth aspects, the control means is configured so that the energy consumption of the main engine is minimized. The pitch angle of the variable pitch propeller is controlled.
The present invention according to claim 8 is the variable pitch propeller control device according to claim 7, wherein the speed of the hull is controlled to be constant before and after the control of the pitch angle. .
According to a ninth aspect of the present invention, in the variable pitch propeller control device according to the eighth aspect of the present invention, the speed of the hull takes into account sea conditions.
With the above configuration, it is possible to control the energy consumption to be minimized while taking into account the influence of response delay in CPP blade angle control. If the speed of the hull is reduced, the energy consumption can usually be reduced. However, if it is necessary to keep the speed of the hull constant, the energy consumption of the main engine is taken into account under the influence of the response delay under these conditions. Control can also be performed to minimize the amount. “Keeping the speed of the hull constant” means that the speed is kept strictly constant before or after the control of the CPP blade angle, or is maintained on the average around the target speed.

According to a tenth aspect of the present invention, in the variable pitch propeller control device according to one of the first to sixth aspects, the control means smoothes the fluctuation of the shaft torque of the drive shaft. The variable pitch propeller is controlled.
The present invention according to claim 11 is the variable pitch propeller control device according to claim 10, wherein the target value of the shaft torque is set by the operating condition setting means, and smoothed so as to approach the target value of the shaft torque. It is characterized by having made it.
According to a twelfth aspect of the present invention, in the variable pitch propeller control device according to one of the first to sixth aspects of the present invention, the control means smoothes fluctuations in thrust of the drive shaft. The variable pitch propeller is controlled.
According to a thirteenth aspect of the present invention, in the variable pitch propeller control device according to the twelfth aspect, the target value of the thrust is set by the operating condition setting means, and smoothing is performed so as to approach the target value of the thrust. It is characterized by what has been done.
With the configuration described above, it is possible to suppress fluctuations in the main engine load by performing control so as to suppress fluctuations in shaft torque or thrust.

According to a fourteenth aspect of the present invention, in the variable pitch propeller control device according to one of the first to sixth aspects, the control means is configured to control the variable pitch based on a prediction result of the predicted inflow velocity. The pitch angle of the variable pitch propeller is controlled so as to follow an envelope that maximizes the propeller efficiency of the propeller.
According to a fifteenth aspect of the present invention, there is provided the variable pitch propeller control device according to the fourteenth aspect, wherein the envelope has a propeller efficiency of a propeller single performance curve group of the variable pitch propeller obtained for each pitch angle. It is an envelope that connects the maximum pitch angle with respect to the forward constant.
By controlling the pitch angle as described above, the propeller efficiency of the variable pitch propeller can be maximized.

A ship according to a sixteenth aspect of the present invention includes the variable pitch propeller control device according to one of the first to fifteenth aspects.
With the above configuration, the same effect as the above-described variable pitch propeller control device can be exhibited as a ship.

A variable pitch propeller control method according to a seventeenth aspect of the present invention includes a setting step of setting operating conditions of a variable pitch propeller driven via a drive shaft by a main engine as a prime mover driving a hull, and the variable pitch propeller A prediction step of predicting the inflow speed of water into the predicted inflow speed at a predicted destination time set in consideration of at least the time delay of the drive system of the variable pitch propeller based on the real-time inflow speed obtained in real time; And a control step of controlling the variable pitch propeller based on the operating condition set in the setting step and the predicted inflow velocity predicted in the prediction step.
With the above configuration, the influence of the response delay in the blade angle control can be suppressed by controlling the variable pitch propeller using the prediction result obtained in the prediction step.

The present invention according to claim 18 is the variable pitch propeller control method according to claim 17, wherein the prediction of the predicted inflow rate of water in the prediction step is real-time measurement of the inflow rate of water into the variable pitch propeller. The prediction is based on the result.
The present invention according to claim 19 is the variable pitch propeller control method according to claim 18, wherein the prediction based on the real-time measurement result is performed based on a time series analysis method or a frequency analysis method. .
The present invention according to claim 20 is the variable pitch propeller control method according to claim 19, wherein the time series analysis method is constituted by a time series model and a model identification method of the time series model. And
The present invention described in claim 21 is the variable pitch propeller control method according to claim 20, wherein the model identification method includes a Burg method, a Yule Walker method, and a House Holder method. , PARCO (PARCOR) method, or Kalman filter.
According to a twenty-second aspect of the present invention, in the variable-pitch propeller control method according to the nineteenth aspect, the frequency analysis method includes a fast Fourier transform method and an inverse fast Fourier transform method.
With the above configuration, the water inflow speed in the prediction step can be accurately predicted.

According to a twenty-third aspect of the present invention, in the variable pitch propeller control method according to one of the seventeenth to twenty-second aspects, the control of the variable pitch propeller in the control step is an energy consumption amount of the main engine. Control that minimizes the shaft torque fluctuation of the drive shaft, control that smoothes the thrust fluctuation of the drive shaft, and the variable that follows the envelope that maximizes the propeller efficiency of the variable pitch propeller. It is selected from among the controls for controlling the pitch angle of the pitch propeller.
According to a twenty-fourth aspect of the present invention, in the variable pitch propeller control method according to the twenty-third aspect, in the control that minimizes the energy consumption, the control method for controlling the pitch angle includes: Based on a control solution obtained by an optimal control theory aiming at minimizing the energy consumption while keeping the speed constant.
According to a twenty-fifth aspect of the present invention, in the variable pitch propeller control method according to the twenty-fourth aspect, the control solution includes a hull motion model, a main engine response model, and a propeller torque model taken into account in the derivation process of the control solution. It is characterized by being.
According to a twenty-sixth aspect of the present invention, in the variable pitch propeller control method according to the twenty-fifth aspect, the hull motion model includes hull resistance, hydrodynamic force due to steering motion, propeller thrust, rudder force, and wave external force as external force terms. It is characterized by including.
According to a twenty-seventh aspect of the present invention, in the variable pitch propeller control method according to the twenty-fifth or twenty-sixth aspect, the main machine response model includes a speed control model of the main machine, a torque generation mechanism of the main machine, and the drive shaft. The response model is included.
According to a twenty-eighth aspect of the present invention, in the variable pitch propeller control method according to the twenty-seventh aspect, the energy consumption is a variable that is incorporated in the speed governing model and is evaluated when the control solution is calculated. It is characterized by being.
With the above configuration, it is possible to suppress load fluctuation of the main machine, suppress energy consumption, and minimize energy consumption.

The variable pitch propeller control device according to the present invention suppresses the influence of response delay in the CPP blade angle control by using the prediction result by the propeller inflow speed prediction means, thereby reducing the main engine trouble due to the suppression of the load fluctuation particularly in the waves. It is possible to realize energy consumption suppression based on optimal control theory and the like. In addition, by predicting the inflow speed based on the measurement result in real time obtained by the torque measurement and thrust measurement of the drive shaft, it is possible to perform the control with high accuracy in consideration of the influence of the response delay.
Moreover, if the information on the incident wave to the variable pitch propeller obtained from the measurement results of the relative water level measuring means and / or the incident wave measuring means and the hull motion measuring means is used, the prediction accuracy of the inflow velocity can be further improved. Is possible.
Further, if the pitch angle of the variable pitch propeller is controlled so that the energy consumption of the main engine is minimized based on the optimal control theory or the like, the energy consumption can be suppressed to be minimized.
In addition, by keeping the hull speed constant before and after the pitch angle control, and controlling the hull speed in consideration of sea conditions, the energy consumption of the main engine is minimized based on the actual operation of the hull. Control can be performed. Further, if the control means smoothes the fluctuation of the shaft torque or the thrust and suppresses the main engine load fluctuation, the main engine load fluctuation can be suppressed and the main engine trouble can be reduced.
Further, if the pitch angle of the variable pitch propeller is controlled so as to follow the envelope that maximizes the propeller efficiency, for example, the energy consumption can be further reduced even if the propeller forward constant changes.
Since the ship of the present invention is equipped with the variable pitch propeller control device of the present invention, it is possible to achieve the same effect as the variable pitch propeller control device described above as a ship.
The variable pitch propeller control method of the present invention suppresses the influence of response delay in CPP blade angle control, and can achieve the same effects as the above-described variable pitch propeller control device of the present invention.

1 is a functional block diagram showing a schematic configuration of a variable pitch propeller control device according to a first embodiment of the present invention. An example of a single performance curve as a characteristic obtained by the propeller open test (a) a graph of a dimensionless value of a propeller thrust called a thrust constant, and (b) a graph of a dimensionless value of a propeller torque called a torque constant. The graph which shows an example of the prediction calculation of an inflow velocity, (a) Prediction destination time: 2.5 second later, (b) Prediction destination time: After 5.0 second Graph showing an example of maximum propeller efficiency envelope Flowchart of a variable pitch propeller control method according to the second embodiment of the present invention.

First, the outline of several existing examples will be introduced as a CPP blade angle automatic control method, and problems of the current technology will be described.
One of the existing examples is a control method using an automatic ship speed adjustment function. This is a control method that automatically adjusts the CPP blade angle and the main engine speed so as to maintain the set ship speed.
Another existing example is a control method using an automatic load control function. This is a control method in which the load on the main machine is reduced by adjusting the CPP blade angle when the main machine is in a load state. In this control method, feedback is performed using measured values of the fuel input amount and the main engine speed.

  Although the CPP blade angle automatic control method exists in addition to the above control method, any of the control methods including the above is feedback control using the latest measurement data as input. In the first place, the CPP blade angle inflection shaft drive system has some response delay with respect to the command value, although there is a difference depending on the drive method.

  However, the conventional automatic CPP blade angle control does not consider the response delay time with respect to the command value, and the followability of the CPP blade angle with respect to the target value is not always satisfactory. Therefore, the inventors of the present invention invented to predict the future value of the measurement data in advance and eliminate the time delay corresponding to the response delay in the CPP blade angle control. As a result of this cancellation, for example, CPP blade angle control corresponding to the propeller inflow speed that varies from moment to moment due to an encounter wave becomes possible without causing follow-up problems. Therefore, it is possible to achieve main machine trouble suppression by suppressing torque fluctuation of the main machine, fuel consumption reduction, and the like with higher effects than the conventional control method.

(First embodiment)
An embodiment in which the present invention is implemented as a variable pitch propeller control device will be described below with reference to the drawings.
FIG. 1 is a functional block diagram showing a schematic configuration of a variable pitch propeller control device according to the present embodiment. As shown in the figure, the variable pitch propeller control device 10 includes a main unit 11, a variable pitch propeller 13 driven by the main unit 11 via a drive shaft 12, an operating condition setting unit 14, a propeller inflow speed prediction unit 15, and a control unit. 16 and a shaft horsepower meter (real-time measuring means) 17 are provided.

  The main engine 11 is a prime mover that drives the hull 18. Here, the “prime mover” refers to an engine that converts energy such as thermal power and electric power into mechanical energy, and the prime mover includes an engine, a motor (electric motor), and the like. The rotational speed of the main machine 11 is measured by a shaft rotational speed measuring means (not shown), and the measurement result is output to the propeller inflow speed predicting means 15 as a shaft rotational speed measurement signal.

  The variable pitch propeller 13 is a device capable of changing the propeller pitch by rotating the propeller blade by the inflection mechanism inside the boss (hub) and changing its angle (CPP blade angle, pitch angle). is there. The CPP blade angle of the variable pitch propeller 13 is controlled by a CPP blade angle control signal corresponding to the command value output from the control means 16. In the control of the CPP blade angle, there is a response delay as described above. The inventors of the present invention pay attention to the response delay of the variable pitch propeller 13, predict a future control input value corresponding to the time to eliminate the response delay, and use this predicted input value to perform CPP blade angle control. As a result, it was found that the influence of response delay can be suppressed, and the present invention has been conceived.

As a result of verification by the inventors, it has been found that the response delay time of the variable pitch propeller 13 in a general ship is usually 1.5 seconds or less. The response delay time was also verified to be within a practical range for predicting propeller inflow speed (this point will be described later with reference to FIG. 3).
Therefore, the variable pitch propeller control device 10 of the present embodiment predicts the operation condition set by the operation condition setting means 14 and the inflow speed of water to the variable pitch propeller 13 predicted by the propeller inflow speed prediction means 15. Based on the above, the variable pitch propeller 13 is controlled. Thereby, the response delay of the variable pitch propeller 13 can be suppressed, and it is possible to reduce the trouble of the main engine 11 and suppress the energy consumption.

  The operating condition setting means 14 sets the operating conditions of the variable pitch propeller 13. The operating condition of the variable pitch propeller 13 is set based on, for example, an instruction input by the operator via the input unit of the operating condition setting unit 14.

  The propeller inflow speed prediction means 15 predicts the inflow speed of water into the variable pitch propeller 13. In the present embodiment, the shaft torque measurement value measured by the shaft horsepower meter 17, the rotation value detected by the main machine 11 or the rotation number set by the operating condition setting means 14, the pitch detected by the variable pitch propeller 13. The inflow speed is predicted based on the measured angle value or the pitch angle set by the operating condition setting means 14 and these three measured values (or set values).

  The control means 16 controls the variable pitch propeller 13 based on the operating condition set by the operating condition setting means 14 and the prediction result of the propeller inflow speed predicting means 15. The propeller inflow speed predicting means 15 predicts the shaft rotation number measurement signal from the main machine 11, the shaft torque measurement signal from the shaft horsepower meter 17, and the CPP blade angle measurement signal from the variable pitch propeller 13 to predict from the operating condition setting means 14. A set value that is a necessary calculation condition is input. This prediction calculation result is input to the control means 16, and various calculations for determining the pitch angle of the variable pitch propeller 13 are performed. Then, a signal (CPP blade angle control signal) for controlling the CPP blade angle of the variable pitch propeller 13 is output to a drive system (not shown) of the variable pitch propeller 13.

  The operating condition setting means 14, the propeller inflow speed prediction means 15, and the control means 16 are configured using, for example, a computer (CPU) (central processing unit), storage means, display means, input means and the like. Since FIG. 1 is a functional block diagram, these are shown separately, but may be configured as a single computer having all these functions.

  The shaft horsepower meter 17 measures the horsepower transmitted by measuring the torsion of the drive shaft 12 that transmits the drive force from the main engine 11 to the variable pitch propeller 13. The shaft horsepower meter 17 includes two types, one that measures torque transmitted by the drive shaft 12 and one that measures thrust (thrust), and either type can be used. Moreover, you may use what combined both. As the sensing means (detection means) of the shaft horsepower meter 17, for example, a highly sensitive displacement sensor using a strain gauge or an amorphous alloy is used.

  In this embodiment, the shaft horsepower meter 17 is used as a real-time measuring means for measuring the inflow speed of water into the variable pitch propeller 13 in real time. Here, “measuring the inflow velocity in real time” means that the inflow velocity is measured immediately, or that a value directly or indirectly related to the inflow velocity is measured immediately. The propeller inflow speed prediction means 15 can predict the inflow speed into the variable pitch propeller 13 based on the measurement result of the shaft horsepower meter 17. This method will be described later.

  The real-time measuring means is not limited to the shaft horsepower meter 17, and for example, a known velocimeter provided at the stern may be used. Moreover, when using a motor as the main machine 11, instead of the shaft horsepower meter 17, a configuration in which the torque of the drive shaft 12 is indirectly measured from the current flowing through the motor may be used.

  The variable pitch propeller control device 10 roughly has three functions (propeller inflow speed measurement, propeller inflow speed prediction, and CPP blade angle control). Hereinafter, a system for realizing each function will be described in order.

(1) Propeller Inflow Speed Measurement System In the propeller inflow speed measurement system of the variable pitch propeller control device 10 of the present embodiment, the shaft torque measured by the shaft horsepower meter 17 in the propeller inflow speed prediction means 15 and the rotation speed of the main machine 11 The rotational speed of the variable pitch propeller 13 obtained from the gear ratio or the rotational speed set by the operating condition setting means 14, the measured value of the propeller pitch angle, or the pitch angle set by the operating condition setting means 14, and torque from these three Using the coincidence method, the propeller inflow speed to the variable pitch propeller 13 is calculated in real time and measured.

  It has been confirmed that the propeller inflow speed can be estimated by the torque matching method not only in flat water but also in waves and during fluctuations in the rotational speed of the variable pitch propeller 13 (Michio Ueno, Yoshiaki Tsukada, Katsuharu Tanizawa: Wave Model experiment on middle propeller inflow velocity, Proceedings of the Japan Society of Marine Science and Technology, No. 12, 2011, pp.419-420. Yasushi Kitagawa, Katsuharu Tanizawa, Yoshiaki Tsukada, Tadayoshi Enomoto: Dynamics on Propeller Thrust and Torque Effect of change, Proceedings of the Japan Society of Marine Science and Technology, No. 13, 2012, pp.237-238.

Formulas representing the torque matching method are shown in formulas (1) to (3).
_{K Qm = Q pm / ρn m} 2 D P 5 ... (1)
_{J P = f (K Qm,} P) ... (2)
_{u Pm = J P · n m} D P ... (3)
In the formulas (1) to (3),
ρ: fluid density,
Q _pm : shaft torque measurement value,
n _m : rotational speed measurement value,
D _P : propeller diameter,
_JP : propeller forward constant,
K _Qm : dimensionless value of propeller torque,
P: propeller pitch angle,
u _Pm : Propeller inflow velocity measurement value.

K _Qm is the torque single performance obtained by the propeller open test.
FIG. 2 is a graph showing an example of a single performance curve as a characteristic obtained by the propeller open test, and the vertical axis (Kt) of (a) shows a dimensionless value of the propeller thrust called a thrust constant. The vertical axis (KQ) of b) represents a dimensionless value of the propeller torque called a torque constant. In both (a) and (b), the horizontal axis represents the propeller advance constant ( _JP ).
As shown in FIG. 2, the characteristic for every pitch angle of the variable pitch propeller 13 is obtained as a single performance curve obtained from the propeller open test. When using the torque matching method, the torque single performance of the variable pitch propeller 13 is preferably arranged in advance by the advance constant _JP and the propeller pitch angle P and functionalized. (2) shows that to derive the J _P from K _Qm, organized by J _P and propeller pitch angle.

  As described above, in the variable pitch propeller control device 10 of the present embodiment, in order to predict the inflow speed to the variable pitch propeller 13 by the propeller inflow speed prediction means 15, the operation condition setting means 14 sets the prediction calculation. In addition, the shaft torque measurement value obtained from the shaft horsepower meter 17 capable of measuring the torque of the drive shaft 12, the single performance curve of the variable pitch propeller 13 (see FIGS. 2A and 2B), and the main engine 11 , And the pitch angle measurement value of the variable pitch propeller 13 are used. By utilizing these, the propeller inflow speed predicting means 15 can predict the inflow speed of water into the variable pitch propeller 13. As described above, the set value set by the operating condition setting means 14 can be used instead of the measured values of the rotation speed and the pitch angle.

  The propeller inflow velocity measuring system can use the thrust matching method instead of the torque matching method described above. In this case, a shaft capable of measuring the thrust of the drive shaft 12 is used as the shaft horsepower meter 17 as the real-time measuring means. Then, the thrust value measured by the shaft horsepower meter 17 is used instead of the value of the shaft torque, and the propeller inflow speed to the variable pitch propeller 13 is calculated in real time to obtain a measured value.

  The variable pitch propeller control device 10 is provided with a filter function for removing noise in the measurement value in order to make a prediction accuracy described later within a practical range. As a means for realizing this filter function, for example, a low-pass filter can be used. Further, by providing a numerical filter in the calculation in the propeller inflow speed prediction means 15 instead of the low-pass filter, the noise of the measurement value can be removed.

(2) Propeller Inflow Speed Prediction System In the variable pitch propeller controller 10, the propeller inflow speed prediction unit 15 constitutes a propeller inflow speed prediction system together with the above-described propeller inflow speed measurement system. In this propeller inflow velocity prediction system, prediction calculation is performed in real time by applying a time series analysis method to the measurement data of the inflow velocity.
Specifically, the future prediction which combined the autoregressive (AR, Auto regressive) model and the Burg method is used. Here, the Burg method is a method for identifying the coefficients in the autoregressive model, and the Yule Walker method, the House Holder method, the Parco method, and the Kalman filter are selected as alternative methods. You can also. Further, as an alternative method of the time series analysis method, a frequency analysis method applying Fast Fourier Transform (FFT) / Inverse Fast Fourier Transform (IFFT) can also be used.

  In this propeller inflow velocity prediction system, the operation condition setting means 14 performs the prediction calculation by setting the number of data samples (or measurement range time) that is the amount of measurement data and the prediction destination time. As a basic property, the prediction accuracy improves when the number of data samples is large, but according to the verification results, further accuracy can be improved by appropriately setting the amount of sample information according to the irregularity of the target time series waveform. Improvement can be achieved. Also, the prediction accuracy tends to improve as the prediction destination time is shorter. In this system, the time delay due to noise filtering and the time delay of the CPP drive system of the variable pitch propeller 13 are grasped in advance, and the total time is set as the predicted destination time. According to the survey results of the ship conducted by the inventors, this total time is 1.5 seconds or less, and it has been verified that the prediction accuracy is guaranteed within a practical range in the blade angle control described later.

FIG. 3 is a graph showing an example of calculation for predicting the inflow velocity, where (a) shows a prediction result after a prediction destination time of 2.5 seconds, and (b) shows a prediction after a prediction destination time of 5.0 seconds. Results are shown. The horizontal axis of these graphs represents the elapsed time and the vertical axis shows the propeller inflow velocity u _P. The dotted lines (original) in FIGS. 3 (a) and 3 (b) indicate the measured values of the propeller inflow velocity having four types of waveform components, and each solid line sets a different number of data samples (Ns). The calculated predicted value is shown.

  The prediction calculation shown in FIGS. 3A and 3B is obtained using measurement data acquired at intervals of 0.1 seconds. For example, when the number of data samples is 100 (Ns: 100), measurement data obtained for 10 seconds before the prediction calculation is used. Specifically, in FIG. 3A, the calculated value of 112.5 seconds of Ns: 100 is predicted at a point of 110 seconds using 100 measurement data obtained between 100 seconds and 110 seconds. The results are shown.

3 (a) and 3 (b), it can be seen that the prediction accuracy is improved by increasing the number of measurement data used for prediction, and the prediction accuracy for the prediction destination time of 2.5 seconds is good. As described above, the total time of the delay time of the CPP drive system of the variable pitch propeller 13 and the time delay due to noise filtering is 1.5 seconds or less. For this reason, if the variable pitch propeller 13 is controlled using the propeller inflow speed predicted by the above-described method, the influence due to the response delay in the blade angle control can be sufficiently suppressed. Here, in order to appropriately set the prediction destination time in the propeller inflow velocity prediction system, the delay time of the CPP drive system and the estimated amount of time delay due to filtering should be verified in advance for the ship on which the apparatus is mounted. It is.
Based on the verification described above, the total time of the delay time and the time delay is 1.5 seconds, and the prediction accuracy of the prediction destination time of 2.5 seconds is good as shown in FIG. It has been verified. From this, for example, if the predicted time is in the range of not less than 1.5 seconds and not more than 2.5 seconds, the influence due to the response delay in the blade angle control can be sufficiently suppressed.

(3) CPP blade angle control system In the variable pitch propeller control device 10, the operating condition setting means 14, the propeller inflow speed prediction means 15, and the control means 16 constitute a CPP blade angle control system. In this CPP blade angle control system, the following blade angle control is performed based on the predicted value of the propeller inflow speed.

1) Torque fluctuation suppression control The control means 16 performs control to suppress torque fluctuation around the shaft torque value set by the operating condition setting means 14. Usually, the propeller torque is estimated as shown in Equation (4) based on the propeller inflow speed, the rotation speed, and the pitch angle. Here, assuming that the shaft torque of the drive shaft 12 and the propeller torque of the variable pitch propeller 13 are equal, the set torque value, the propeller inflow speed obtained as a predicted value by the propeller inflow speed predicting means 15, and the predicted value of the rotational speed are given. If the equation (4) is rearranged, the target pitch angle (CPP blade angle) that always maintains the set torque value can be obtained in real time as shown in the equation (5). Note that the rotation speed of the variable pitch propeller 13 may be a value set by the operating condition setting means 14 such as an average value of past measurement values instead of a predicted value. The control means 16 controls the CPP blade angle of the variable pitch propeller 13 using this target pitch angle.
^{_{Q p = ρn p 2 D p}} 5 · K Q [u P, n p, P] ... (4)
P _set = g (QP _set , u _Predicted , n _Predicted ) (5)
However, in Formula (4) (5),
ρ: fluid density,
Q _p : propeller torque,
n _p : propeller rotation speed,
D _p : propeller diameter,
K _Q : Propeller torque independent performance,
u _P : Propeller inflow speed,
P: propeller pitch angle,
P _set : propeller pitch angle target value,
QP _set : Shaft torque set value,
u _Ppredicted : propeller inflow velocity prediction value,
n _Ppredicted : propeller rotation speed predicted value.
As described above, the control means 16 controls the variable pitch propeller 13 so as to smooth the fluctuation of the drive shaft 12 around the shaft torque set as the target value. Due to the effect of this control, it is possible to suppress the load fluctuation of the main machine 11 and prevent the occurrence of trouble.

2) Thrust fluctuation suppression control The control means 16 may use a thrust value as a target value instead of the above-described shaft torque. In this case, control is performed to suppress the thrust fluctuation around the set thrust value. Even when the thrust value is used as the target value, the method described for the shaft torque is the same. For this reason, the detailed description is omitted.
By smoothing the fluctuation of the shaft torque or thrust of the drive shaft 12 by the control means 16, it becomes possible to prevent the occurrence of a main engine trouble in the same manner as the torque fluctuation suppression control.

3) Maximum control of propeller efficiency From the propeller open test of the variable pitch propeller 13 mounted on the variable pitch propeller control device 10, an envelope curve that maximizes the propeller efficiency with respect to the propeller forward constant Jp is prepared. Then, the control means 16 performs control so that the propeller pitch angle always exists on the envelope based on the forward constant calculated from the predicted value of the inflow velocity. Thereby, the control that maximizes the propeller efficiency of the variable pitch propeller 13 can be realized.

FIG. 4 is a graph showing an example of an envelope having the maximum propeller efficiency. In the figure, the horizontal axis represents the propeller forward constants J _P of the variable pitch propeller 13, a vertical axis indicates the propeller efficiency of the variable pitch propeller 13, a dotted line indicates a propeller efficiency maximum envelope. Propeller efficiency maximum envelope points propeller efficiency is maximized with respect to the propeller forward constants J _P, a line connecting choose from the entire Propeller performance curves of the variable pitch propellers 13 obtained for each pitch angle. That is, the presence of the pitch angle on the envelope means that the propeller efficiency is always maximized during navigation.
The control means 16 calculates the forward constant based on the prediction result of the inflow speed, and controls the pitch angle (CPP blade angle) of the variable pitch propeller 13 so as to follow the envelope that maximizes the propeller efficiency of the variable pitch propeller 13. By doing so, the propeller efficiency can be maximized.

4) Minimum fuel consumption control The control means 16 is modeled by setting the objective function that minimizes fuel consumption by modeling the main engine response, torque fluctuation, hull motion, etc. in the waves as a state equation. Blade angle control is performed based on the control solution of the propeller pitch angle derived by solving the control problem. Thereby, the pitch angle of the variable pitch propeller 13 can be controlled so that the energy consumption of the main unit 11 is minimized.

  Among the optimal control problems, keeping the ship speed during wing angle control is a constraint. That is, the control means 16 performs control so that the speed of the hull is kept constant before and after the control of the pitch angle. For this reason, the operation which suppresses fuel consumption to the minimum under the designated ship speed becomes possible. The control solution is obtained extensively under the wave conditions where the encounter is expected, and is used properly based on the waveform information of the propeller inflow velocity to be measured.

  In addition, since the calculation process for obtaining the control solution generally requires a long time, it is often difficult to obtain the control solution in real time by the control means 16 when the ship navigates. Therefore, a control solution is obtained in advance for each setting condition based on the sea condition that is assumed to be encountered during vessel navigation, such as main engine response, torque fluctuation, hull motion, etc. in the waves, and the setting condition is stored in the storage means of the control means 16. And the control solution are preferably stored as a corresponding table. According to this configuration, by using the predicted value corresponding to the set condition obtained from the propeller inflow velocity predicting means 15, the control using the control solution is performed without obtaining the control solution in real time. be able to.

  In addition, the control means 16 controls the pitch angle so that the speed of the hull is constant in consideration of sea conditions. Here, “considering sea conditions” includes an increase in resistance of the hull in the waves, a forcing force received by the hull due to the waves, and the like.

The variable pitch propeller control device 10 includes a relative water level measuring means 19, an incident wave measuring means 20, and a hull motion measuring means 21 in the hull 18.
The relative water level measuring means 19 measures the distance from the position to the water surface, and examples thereof include an ultrasonic type and an electromagnetic type. The relative water level measuring means 19 can measure a change in the height of the water surface. For this reason, the wave incident on the variable pitch propeller 13 can be evaluated based on the measurement result.
The incident wave measuring means 20 directly measures waves incident on the hull 18 by directly measuring the sea surface.
The hull motion measuring means 21 measures the motion of the hull 18, and for example, a gyroscope or an accelerometer can be used.

  Based on the measurement results of the relative water level measurement means 19 and / or the incident wave measurement means 20 and the hull motion measurement means 21, it is possible to obtain the relative motion between the propeller and the fluid due to the wave and hull motion at the position of the variable pitch propeller 13; From this, the propeller inflow speed can be predicted. For this reason, the control means 16 may use the relative water level measurement means 19 and / or the measurement results of the incident wave measurement means 20 and the ship motion measurement means 21 as an alternative method in predicting the inflow velocity into the variable pitch propeller 13. it can.

  The present invention can also be implemented as a ship equipped with the above-described variable pitch propeller control device of the present embodiment. Even when the present invention is implemented as a ship, the same effect as the above-described variable pitch propeller control device can be obtained.

(Second Embodiment)
The present invention can be implemented as a variable pitch propeller control method including the following flows (steps) (1) to (3) and a variable pitch propeller control device that implements this flow (see FIG. 1).
(1) The shaft torque from the shaft horsepower meter 17 to the drive shaft 12, the propeller rotation speed from the main gear 11 and the gear ratio, the propeller pitch angle from the variable pitch propeller 13, and the variable pitch propeller 13 from these measured values and set values by the torque matching method. Measure the propeller inflow speed to.
(2) By performing time-series analysis on the measurement data, the total time ahead of the variable pitch propeller 13 drive system response delay and the time delay due to the measurement data filtering (future time point separated by a time equal to the total time) Predict the propeller inflow speed.
(3) The blade angle control of the variable pitch propeller 13 is performed using the predicted value of the propeller inflow speed.
By using this method, it becomes possible to control the variable pitch propeller 13 corresponding to the inflow speed of water that fluctuates from moment to moment due to encounter waves (waves flowing into the variable pitch propeller 13) and ship motion.

  This variable pitch propeller control method is obtained from a control method that smoothes torque fluctuations and thrust fluctuations, a control method that keeps the propeller efficiency at a maximum, and an optimal control theory that minimizes the fuel input at a specified ship speed. A control method based on the obtained control solution can be used. These control methods can be expected to provide safe operation by suppressing fluctuations in the main engine load and improved propulsion performance in waves.

Below, the aspect which implements this invention as a variable pitch propeller control method is demonstrated with reference to drawings.
FIG. 5 is a flowchart according to the variable pitch propeller control method of the present embodiment. As shown in the figure, the variable pitch propeller control method of the present embodiment includes a setting step S1, a prediction step S2, and a control step S3.

  The setting step S <b> 1 sets operating conditions of the variable pitch propeller 13 driven by the main engine 11 as a prime mover that drives the hull 18 through the drive shaft 12 and calculation conditions of the propeller inflow speed predicting means 14. In the variable pitch propeller control device 10, the operator inputs a set value from the input means of the operating condition setting means 14.

  Prediction step S <b> 2 predicts the inflow speed of water into the variable pitch propeller 13, and is performed by the propeller inflow speed prediction means 15. The prediction of the inflow speed of water in the prediction step S2 is made based on the result of measuring the inflow speed of water into the variable pitch propeller 13 in real time. Here, as described in the first embodiment, the object to be measured includes not only the water inflow speed itself but also a value obtained by measuring an event directly or indirectly related thereto.

The prediction based on the real-time measurement result which is the result of the real-time measurement can be performed based on the time series analysis method or the frequency analysis method. The “time series analysis method” used in the present invention refers to a method of predicting a future state quantity displacement of a measurement target by modeling the state quantity displacement in the time domain of the measurement target.
The constituent elements of the “time series analysis method” include a time series model and a model identification method of the time series model. “Time-series model” refers to state quantity displacement at a certain time point, input information at that time point, state quantity displacement at other time points such as state quantity displacement measured in the past, and coefficients related to the displacement, The model explained from these elements. The “time series model identification method” is a method for identifying coefficients constituting the time series model. And future prediction is performed by calculating | requiring the state quantity displacement of the prediction time ahead set in the identified time series model.

Examples of the model identification method include a Burg method, a Yule Walker method, a House Holder method, a Parco method, and a Kalman filter.
Examples of the “frequency analysis method” include a method constituted by a fast Fourier transform method and an inverse fast Fourier transform method.

The control step S3 controls the variable pitch propeller 13 based on the operating condition set in the setting step S1 and the inflow velocity prediction result in the prediction step S2, and is performed by the control means 16.
Specifically, the control of the variable pitch propeller 13 in the control step S3 includes control for minimizing the energy consumption of the main engine 11, control for smoothing the shaft torque fluctuation of the drive shaft 12, and thrust fluctuation of the drive shaft 12. Control for smoothing, control for controlling the pitch angle of the variable pitch propeller 13 so as to follow an envelope (see FIG. 4) that maximizes the propeller efficiency of the variable pitch propeller 13 can be used.

The control of the variable pitch propeller 13 in the control step S3 is based on a control solution obtained by an optimal control theory for the purpose of minimizing energy consumption in the control method for controlling the pitch angle.
In the present invention, “optimal control theory” means (1) formulation of model equations and constraint conditions for the target control system, and (2) maximum set objective function for input conditions. A control theory that derives a control command amount that satisfies the requirements as a control solution.

Here, in the process of deriving the control solution obtained by the optimal control theory, the luck model of the hull 18, the response model of the main engine 11, and the propeller torque model of the variable pitch propeller 13 are considered.
Here, the response model of the main machine 11 includes a speed control model of the main machine 11, a torque generation mechanism of the main machine 11, and a dynamic model as a rotating body of the drive shaft 12. The energy consumption is a variable that is incorporated in the speed control model and is evaluated when calculating the control solution. When the main machine 11 is an engine, the speed control model is a governor response model.
Examples of the motion model of the hull 18 include a hull resistance of the hull 18, a fluid force due to a steering motion, a propeller thrust, a rudder force, and a wave external force as external force terms.

  The present invention eliminates the delay in response of the pitch angle drive system, and in particular, can reduce the main engine trouble in the waves and can suppress the energy consumption based on the optimal control theory, etc., so that the ship equipped with a variable pitch propeller Can be used for etc.

DESCRIPTION OF SYMBOLS 10 Variable pitch propeller control apparatus 11 Main machine 12 Drive shaft 13 Variable pitch propeller 14 Operating condition setting means 15 Propeller inflow speed prediction means 16 Control means 17 Shaft horsepower meter (real-time measurement means)
18 Hull 19 Relative water level measuring means 20 Incident wave measuring means 21 Hull motion measuring means

Claims (28)

The main engine as the prime mover driving the hull,
A variable pitch propeller driven by the main machine via a drive shaft;
Operating condition setting means for setting operating conditions of the variable pitch propeller;
A propeller that predicts the inflow speed of water to the variable pitch propeller as a predicted inflow speed at a predicted destination time set in consideration of at least a time delay of the drive system of the variable pitch propeller based on a real time inflow speed obtained in real time Inflow velocity prediction means,
Variable pitch propeller control system characterized by comprising a control means for controlling the variable pitch propeller based on the predicted inflow velocity predicted by the propeller inflow velocity predicting means and the set operation condition by the operation condition setting unit . The variable according to claim 1, wherein the prediction of the predicted inflow speed by the propeller inflow speed prediction means is prediction based on a measurement result of a real-time measurement means provided for measuring the inflow speed in real time. Pitch propeller control device.   The variable pitch propeller control device according to claim 2, wherein the real-time measuring means is a shaft horsepower meter capable of measuring torque of the drive shaft.   The variable pitch propeller control device according to claim 2, wherein the real-time measuring means is a shaft horsepower meter capable of measuring thrust of the drive shaft. 5. The variable pitch according to claim 3, wherein a single performance curve of the variable pitch propeller, a rotational speed of the main engine, and a pitch angle of the variable pitch propeller are used for the prediction of the predicted inflow velocity. Propeller control device. The hull further comprises a relative water level measuring means and / or incident wave measuring means and a hull motion measuring means,
3. The variable pitch propeller control device according to claim 2, wherein measurement results of the relative water level measurement means and / or the incident wave measurement means and the hull motion measurement means are used for the prediction of the predicted inflow velocity.   7. The variable pitch propeller according to claim 1, wherein the control means controls the pitch angle of the variable pitch propeller so that the energy consumption of the main engine is minimized. Control device.   8. The variable pitch propeller control device according to claim 7, wherein control is performed so that the speed of the hull is kept constant before and after the control of the pitch angle.   9. The variable pitch propeller control device according to claim 8, wherein the speed of the hull takes into account sea conditions.   The variable pitch propeller control according to any one of claims 1 to 6, wherein the control means controls the variable pitch propeller so as to smooth the fluctuation of the shaft torque of the drive shaft. apparatus.   The variable pitch propeller control device according to claim 10, wherein a target value of the shaft torque is set by the operating condition setting means, and smoothing is performed so as to approach the target value of the shaft torque.   7. The variable pitch propeller control device according to claim 1, wherein the control means controls the variable pitch propeller so as to smooth the fluctuation of the thrust of the drive shaft. 8. .   13. The variable pitch propeller control device according to claim 12, wherein a target value of the thrust is set by the operating condition setting means, and smoothing is performed so as to approach the target value of the thrust. The control means controls the pitch angle of the variable pitch propeller so as to follow an envelope that maximizes the propeller efficiency of the variable pitch propeller based on a prediction result of the predicted inflow velocity. The variable pitch propeller control device according to claim 1.   The envelope is an envelope formed by connecting a pitch angle at which a propeller efficiency is maximum with respect to a propeller forward constant with respect to a propeller independent performance curve group of the variable pitch propeller obtained for each pitch angle. Item 15. The variable pitch propeller control device according to Item 14.   A ship equipped with the variable pitch propeller control device according to one of claims 1 to 15. A setting step for setting operating conditions of a variable pitch propeller driven via a drive shaft by a main engine as a prime mover for driving the hull;
Prediction for predicting the inflow speed of water into the variable pitch propeller as a predicted inflow speed at a predicted destination time set in consideration of at least a time delay of the drive system of the variable pitch propeller based on the real time inflow speed obtained in real time Steps,
A variable pitch propeller control method comprising: a control step of controlling the variable pitch propeller based on the operating condition set in the setting step and the predicted inflow velocity predicted in the prediction step. 18. The variable pitch propeller control method according to claim 17, wherein the prediction of the predicted inflow speed of water in the prediction step is a prediction based on a real-time measurement result of the inflow speed of water into the variable pitch propeller. .   The variable pitch propeller control method according to claim 18, wherein the prediction based on the real-time measurement result is performed based on a time series analysis method or a frequency analysis method. The variable pitch propeller control method according to claim 19, wherein the time series analysis method includes a time series model and a model identification method of the time series model.   21. The model identification method is selected from any of a Burg method, a Yule Walker method, a House Holder method, a PARCO method, and a Kalman filter. The variable pitch propeller control method described in 1.   20. The variable pitch propeller control method according to claim 19, wherein the frequency analysis method is configured by a fast Fourier transform method and an inverse fast Fourier transform method.   The control of the variable pitch propeller in the control step includes control for minimizing energy consumption of the main engine, control for smoothing shaft torque fluctuation of the drive shaft, control for smoothing thrust fluctuation of the drive shaft, The control unit is selected from among controls for controlling a pitch angle of the variable pitch propeller so as to follow an envelope that maximizes a propeller efficiency of the variable pitch propeller. The variable pitch propeller control method described in 1.   In the control that minimizes the energy consumption, the control method for controlling the pitch angle is an optimal for the purpose of minimizing the energy consumption while keeping the speed of the hull constant before and after the control. The variable pitch propeller control method according to claim 23, which is based on a control solution obtained by a control theory.   The variable pitch propeller control method according to claim 24, wherein a ship motion model, a main engine response model, and a propeller torque model are considered in the process of deriving the optimal control solution.   26. The variable pitch propeller control method according to claim 25, wherein the hull motion model includes hull resistance, fluid force due to steering motion, propeller thrust, rudder force, and wave external force as external force terms.   27. The variable pitch propeller control method according to claim 25 or claim 26, wherein the main machine response model includes a speed control model of the main machine, a torque generation mechanism of the main machine, and a response model of the drive shaft.   28. The variable pitch propeller control method according to claim 27, wherein the energy consumption is a variable that is incorporated in the speed control model and is evaluated when the control solution is calculated.