JPS60193008A - Feedforward control method for oscillation or the like of floating matter using incident wave signal - Google Patents

Abstract

PURPOSE:To control properly the oscillations of a fixed matter or a floating matter by detecting an incident wave signal at the front of a matter set at the wave incident side and using the detected incident wave signal to change the parameter of an external dynamic system. CONSTITUTION:For a wave absorbing energy device E, an air pass port 3 is formed at the upper part of a fixed matter 1 set on waves together with a variable nozzle 2 and a duct 4 set at the lower and upper end parts of the port 3 respectively. A Wales turbine 5 is provided within the duct 4, and the power of the turbine 5 is transmitted to an energy absorber main body G of a generator 8, etc. via a belt 7, etc. In addition, a detection device such as a wave motion measurement device, etc. is provided to the device E at the front of a matter set at the wave incident side. The detection value of said detection device undergoes the arithmetic processing through an arithmetic device to control the size of a variable nozzle 2 as well as the capacity value of a variable capacitor of an electric circuit. Thus the flowing speed of the air passing through the turbine 5 is kept at an optimum state. At the same time, the revolutions of the generator 8 are changed to obtain synchronization with a wave cycle to obtain the highest absorption efficiency of energy.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a wave energy absorption device, a vibration prevention device for ships,
It is applied to fields such as wave-dissipating and wave-making devices, and relates to a feedforward control method that uses incident wave signals to control the state of a fixed object or the movement of a floating body due to waves.

(Prior Art) Many studies have been conducted since ancient times on wave control, that is, on avoiding the influence of waves or on effectively utilizing waves. The former aims to reduce or eliminate the movement of ships, etc. due to the influence of waves, and the latter aims to effectively utilize wave energy. In order to absorb wave energy, it is necessary to control the motion of a fixed object or floating object in some way, but the control method for regular waves has been established both theoretically and experimentally. . However, for irregular waves, the parameters (damping force coefficient, restoring force coefficient, etc.) of the external dynamical system (additional dynamical system) added to the E fixed object or floating body (or included in the floating body itself) (hereinafter the same) has been studied by fixing it to a value that indicates the liquid efficiency at a specific representative frequency of the irregular wave spectrum (hereinafter referred to as a fixed coefficient system). However, the wavelength (wave period) in the actual ocean (including lakes, etc.; the same applies hereinafter) constantly changes with a considerable range of fluctuation, and such a fixed coefficient system cannot achieve sufficient control effects at wavelengths other than that specific one. can't get it.

Therefore, in order to effectively control waves, a detection means is provided in the external dynamical system itself to detect changes in the waves, and the parameters of the external dynamical system are changed and controlled according to the wavelength state of the waves. It is possible to introduce a so-called variable coefficient control system.

However, the L control method has a drawback in that the reaction speed of hardware (physical mechanisms such as mechanical, electrical, etc.) requires time.

(Objective of the invention) This invention was made in view of the above-mentioned current situation, and in order to effectively control waves in irregular waves, -1; This signal is then used to determine the state of a fixed object or the movement of a floating body (
In other words, it is an object of the present invention to provide a method for controlling reflected waves, transmitted waves, etc.).

(Structure and operation of the invention) The present invention provides a variable coefficient control system for changing parameters such as a damping force coefficient or a restoring force coefficient of an external dynamic string attached to a fixed object or a floating body placed in a wave or fire. A detection means is provided in front of the object where the waves are incident,
By changing the parameters of the external dynamical system using the incident wave signal detected by this detection means, it is possible to always appropriately control the state of a fixed object or the movement of a floating body in response to fluctuations in the wavelength of irregular waves. It consists of a feedforward control method characterized by the following.

Examples of the present invention will be described below.

In this embodiment, this control method is applied to a wave absorption energy device. Figure 1 is a side sectional view of the wave energy absorption device, and ■ is a fixed object installed on the wave.
An air inlet 3 is attached to the upper part of this fixed object 1,
A variable nozzle 2 is formed at the lower end of the air inlet/outlet 3, and a duct 4 is formed at the upper end. And the above duct 4
A Wells turbine 5 having a diameter slightly smaller than the inner diameter of the duct 4 is installed inside. This Wells turbine 5 is connected to a generator 8, etc., which is equipped with an electric circuit 15 (see FIG. 2) consisting of a variable capacitor 16, etc., which constitutes a spring system in wave control, via a transmission mechanism such as a pulley 6, a belt 7, etc. The structure is such that rotation is transmitted to the energy absorbing device main body G of. Thus, in this wave energy absorbing device E, the amount of air existing in the lower space portion 9 surrounded by this device E and the sea surface is changed by the wave movement in the vertical direction of the waves. That is, when the sea level falls, the space 9 becomes under negative pressure, and external air flows into the space 9 from the air inlet/outlet 3. Furthermore, when the sea level rises, the air in the space 9 is compressed and tends to flow out from the air inlet 3. The Wells turbine 5 installed in the duct 4 of the air inlet/outlet 3 is rotated as the air flows in or out. Furthermore, as shown in FIG. 3, the wave energy absorbing device E is provided with a detecting means, that is, a detecting device F consisting of a wave measuring device or the like in front of the object on which the waves are incident.

Then, the value detected by the detection device F mentioned above is transmitted to a calculation device, where a predetermined calculation process is performed, and based on the result, the nozzle diameter of the variable nozzle 2 of the air inlet/outlet 3 is determined. The size and value of the capacitance of the variable capacitor 16 of the electric circuit 15 are controlled. That is, by controlling the nozzle diameter, the fluid resistance (damper system reduction force coefficient) of air flowing out from the space 9 of the fixed object 1 of the wave energy absorbing device E or flowing into the space 9 from the outside is reduced. ) to maintain the flow rate of air passing through the 5 parts of the Wells turbine always at an optimum state. - By controlling the value of the capacity of the variable condenser 16, the rotation of the generator 8 (spring system: restoring force coefficient) of the wave energy absorption device E is changed, thereby controlling the rotation of the Wells turbine 5. By changing the flow of air passing through the 5th section of the Uturzu turbine, the condition is optimal for lightning (a condition in which the waves and the rise and fall of the sea level on one side of the above space are synchronized).
to be maintained.

That is, - the rise and fall of the sea surface below the space can be synchronized with the cycle of waves, and the wave energy absorption efficiency can be maintained at the highest level.

Next, a stationary method for controlling the parameters of the external mechanical thread, such as the nozzle diameter of the variable nozzle, from the above-mentioned detected values will be described. For the sake of explanation, we will now explain a control method for a two-dimensional model using a variable spring 10 and a variable damper 11 as parameters of the external dynamic system, as shown in FIG. The spring string means, which is one of the control means, uses a variable spring IO, which corresponds to the variable capacitor in the above embodiment. As the damper system means, a variable damper 11, which corresponds to the variable nozzle of the above embodiment, is used. The following explanation of this control will be exclusively about the spring thread (spring system control). The floating body 14 corresponds to the space portion 9 (see FIG. 1) in the above embodiment. That is, 1- of the floating body
The fluctuation in the downward motion corresponds to the fluctuation in the downward motion of the iceberg in the downward space.

In FIG. 4, a detection means F is provided at point A, and detects an incident wave signal (also called wave information) at point A.

same as below. ) is ζA(t), the wave ζa at point B
(t) is, Here, ζ8, ζB represent wave information in time domain expression, 4A8(T,) = a ((J53 near, +((+nor), "' +112 "C multilayer ) J to---------
(1) In order for the floating body to synchronize instantaneously with the waves at point B, the parameters of the external dynamic system, that is, the spring characteristics, may be set to values expressed by the following formula.

Here, K(τ) in the above equation is the time history of the parameters of the external dynamical system for instantaneous tuning to the incident wave signal at point A, that is, when controlling the variable spring.
It shows the impulse response of the spring coefficient, which is expressed by the following equation.

In addition, A)l in the above formula is the divergent wave amplitude ratio, and h(
τ2) is the impulse response of the floating body to the waves when the floating body is tuned to the incident wave signal of the waves at point A, when the wave characteristics are satisfied.

That is, in this quadratic yc model (see Figure 4), if we control the force of the spring that connects the floating body and the fixed side (pier, etc.), which is the external dynamic system, to the value of M (t) above, then good.

In addition, although the explanation in item 1-1 was exclusively about the control of the spring thread, in actual control, the damper thread is also controlled using the same method based on the instantaneous damping force. That is, The damping force characteristic N(ω) of the floating body is inversely Fourier transformed, the instantaneous damping force n(t) is determined, and the impulse response under this condition is determined as (τ2), - Equation (2) above. K(τ
) , h (rx), the time-domain expression of the optimal damping characteristic of the external mechanical thread can be obtained.

In a controlled object (energy absorption device, ship, etc.) that has a spring system and a damper system, the spring characteristics and damping characteristics determined using the method described in section 2 can be added and controlled to satisfy them.

As explained above, a detection means F (wave measuring device) etc. is provided on the wave propagation direction hydraulic force of a solid or floating body (point A in Fig. 4), and using the incident wave signal detected by this detection means, Satisfies the wave transfer function HGS (ω) from point A to point B that is input to the calculation device and the spring characteristics or tamper characteristics to synchronize the floating body with the waves and provide *a external damping force. Based on the impulse response h(τ) and hbaτ) of the floating body to waves, the motion of the floating body is optimized to absorb wave energy most efficiently.

Here are the numerical simulation results at the model level of the floating body's vertical velocity 2 and absorbed power W(t) for the variable coefficient yarn system and fixed coefficient system according to the present invention under the same wave conditions. Shown in Figures 5 and 6. These clearly represent the superiority of the variable coefficient system in terms of energy absorption efficiency.

In the above, we have mainly explained the application of wave energy to pneumatic and floating power generation devices, etc., but in the wave energy generation device etc. shown in FIG.
The '#1ml1l force method of the present invention can also be applied to a flap-type structure using a floating body instead of a floating body. Also,
As shown in FIG. 9, the control method of the present invention can also be applied to a wave-making/wave-dissipating device in an experimental water tank or the like using a wave-producing/wave-dissipating plate 18 instead of a floating body. Furthermore, as shown in FIG.
It is also possible to provide the fin 12 outside the ship and the fin 12 on the belly of the ship, and apply it to the pitching and rolling prevention device of the ship 13.

(Effects of the Invention) As explained above, this invention can effectively control the state of a fixed object or the movement of a floating body in irregular waves. It is an excellent invention that contributes to the safe navigation of ships in the field of preventing vibrations of ships, etc. by promoting its practical application through the improvement of absorption efficiency.

[Brief explanation of drawings]

Figure 1 is a side sectional view of the main body of the wave energy absorption device, Figure 2
The figure is a circuit diagram showing an electric circuit that is a control means for the spring system, Figure 3 is a side view of the wave energy absorption device, and Figure 4 is a wave energy absorption diagram for explaining a specific control method according to the present invention. A side view of the two-dimensional model of the device, Figure 5 is a diagram showing the energy absorption efficiency of the fixed coefficient thread system, Figure 6
The figure shows the energy absorption efficiency of the variable coefficient system, and FIGS. 7, 8, and 9 show other application examples. E... Wave energy absorption device, F... Detection device,
G...Energy absorption device main body, 1...Fixed object,
2...Variable nozzle, 3...Air inlet/outlet, 4...
Duct, 5... Wells turbine, 6... Pulley,
7... Belt, 8... Generator, 9... Lower space portion, 10... Variable spring, 11... Variable damper, 12
River fin, 13...ship, engineering 4...floating body, 15...
・Electrical circuit, 16...variable capacitor, 17...
Flap, 18... Wave-making/wave-dissipating plate, Engineering 9... Ultrasonic measuring device, 2o... Acceleration needle. Procedural amendment (voluntary) 1. Indication of the incident 1978 Poetry written by permission number 49649
No. 2, Title of the invention Feedforward control method for the motion of a floating body, etc. using incident wave signals 3, Relationship with the case of the person making the amendment Patent Representative: Kenhiro Haseyo 4, Agent: 〒650〒 -2゛2

Claims (1)

[Claims] In a variable coefficient system U〆 control system that changes parameters such as damping force coefficient or restoring force coefficient of an external dynamic system added to a fixed object or a floating body placed in a wave.
, by installing a detection means in front of the object on the side where the waves are incident, and using the incident wave signal detected by this detection means to change the parameters of the external mechanical thread, it can be fixed against fluctuations in the wavelength of irregular waves. A feedforward control method characterized in that the state of an object or the movement of a floating body can be appropriately controlled at all times.