JP7232532B2 - ENGINE CONTROL METHOD, ENGINE CONTROL PROGRAM AND ENGINE CONTROL DEVICE USING ENGINE STATE OBSERVER - Google Patents

Description

The present invention relates to an engine control method, an engine control program, and an engine control apparatus for controlling an engine equipped with an exhaust valve and fuel control means using an engine state observer for estimating the engine state from an engine model.

In recent years, environmental regulations on ship propulsion plants have been strengthened more and more, and _CO2 reduction regulations represented by EEDI (Energy Efficiency Design Index) have also been strengthened. Propulsion plants require various countermeasures to comply with these regulations, and the system is becoming more complex. Therefore, there is a need for advanced control technology that automatically adapts to actual sea conditions for propulsion plants.
In the real-sea area automatic application control technology, there is a propulsion plant that controls the propulsion plant by creating a virtual plant using a propulsion plant simulator and comparing it with the actual plant. The heart of the propulsion plant is the engine, and the engine model needs to be a faithful representation of the actual engine, yet easy to compute for real-time control.

The most important state parameters for engine performance are the amount of fuel and the amount of air required for its combustion. ) must be properly controlled. However, none of these parameters can be measured accurately, especially in non-stationary conditions, and cannot be used for control.

Also, in order to maintain engine performance at maximum efficiency, it is necessary to keep engine state parameters at optimum values under given operating conditions. There are two conventional control methods for controlling engine performance, one is open loop control and the other is closed loop control.
Open-loop control is a method in which the relationship between control actions and state parameters is created in advance as a steady-state map and used for control. Open-loop control is simple, but it cannot be applied to engine performance control, which requires complicated control, because the map cannot be applied when the engine condition changes due to deterioration over time.
Closed loop control is currently most used. Closed-loop control is control that measures an engine state parameter (most simply, engine speed) and minimizes the difference from the optimum set value. However, although PID control, which can be said to be representative of conventional closed-loop control, is linear control, the actual engine state is nonlinear, and the method using linear control cannot be said to be optimal. In order to compensate for this, it is necessary to create a map in advance and use it according to the engine state, as in open loop control. It takes an enormous amount of time because it is necessary to Moreover, it cannot be guaranteed that the created map covers non-linearity unique to the engine. Further complicating the problem is the reliability of the measurement sensor, which may lead to erroneous measurements due to deterioration, and even if measurements are made, they may contain a lot of noise, making highly accurate control impossible.

Here, in Patent Document 1, parameter values such as temperature acquired by an engine sensor are input to a state estimator equipped with an extended Kalman filter (EKF), and the input parameter values and the engine prediction model are used. is used to estimate the state of the engine by estimating non-measured or non-sensed parameters, and an optimization algorithm is used to generate commands for the actuators based on the state and to send the commands to the engine to estimate engine performance. A method for optimization is disclosed.
Further, Patent Document 2 has a plurality of cylinders connected to a manifold, a detector for estimating the air-fuel ratio downstream of the manifold, and an estimator equipped with an extended Kalman filter (EKF). A method of estimating the air-fuel ratio of each cylinder by inputting the delay time and the air-fuel ratio determined by the number and the angle of the crankshaft into an estimator is disclosed.
Further, Patent Document 3 discloses a method of measuring the crank angle of the crankshaft of an engine, calculating the crank angular speed estimation error and the crank angle estimation error, and estimating the engine torque using a nonlinear Kalman filter.
Further, in Patent Document 4, according to the oil water temperature and the supply air pressure that change depending on the external environment, etc., the predetermined sealing period of the combustion chamber (after the exhaust valve is closed until the intake valve is opened). A valve timing control device is disclosed that corrects the closed period), the intake valve closing timing, the fuel injection amount during the closed period, and the like.

JP 2005-248946 A Japanese Patent Application Laid-Open No. 2006-336645 JP 2017-82662 A JP-A-2002-129991

However, technology that accurately estimates the excess air ratio, which is the most important state parameter in engine performance, even in unsteady conditions, allows the engine state to be understood, and the engine is efficiently controlled based on the estimated excess air ratio. has never been proposed.

Therefore, the present invention estimates an excess air ratio using an engine model, and controls the engine based on the estimated excess air ratio to maintain engine performance at maximum efficiency even in an unsteady state. An object of the present invention is to provide an engine control method, an engine control program, and an engine control device using an observer.

In the engine control method using the engine state observation device corresponding to claim 1, the engine state observation is performed by estimating the engine state of a two-stroke engine equipped with an exhaust valve, a fuel control means, and a supercharger by an engine model. An engine control method for controlling using a device, comprising state parameters consisting of engine speed, supercharger speed of a supercharger, scavenging pressure, exhaust temperature, exhaust pressure, and engine load, and engine dynamics , the engine model parameters, and the fuel pump rack value of the fuel regulation means into a nonlinear state-space equation, which is the engine model that describes how the state parameters change with an update of the fuel pump rack value. On the other hand, the initial state values of the state parameters are set, and the engine speed, the fuel pump rack value, and the exhaust valve opening of the engine that drives the propeller that causes the load fluctuation due to the disturbance in the actual sea area of the ship The engine speed or operation timing is detected as a sensor value and input to the engine model of the engine state observer, and the state parameters are estimated using the state initial value and fuel pump rack value of each state parameter in the nonlinear state space equation. The observed state parameters are observed and used as observation parameters, the observation parameters and the engine speed as sensor values are applied to the Kalman filter to correct the observation parameters, and the corrected observation parameters are the engine speed and the sensor value as the fuel pump. Find the fuel amount from the rack value, find the air amount to the engine based on the relational expression of the turbocharger rotation speed, scavenging pressure, exhaust temperature, exhaust pressure, and air amount as corrected observation parameters, The excess air ratio is estimated from the amount of fuel, the amount of air to the engine, the exhaust valve opening or operation timing as a sensor value, and the scavenging efficiency of the engine obtained in advance. When the estimated excess air ratio falls below the reference excess air ratio, control at least the exhaust valve opening degree of the exhaust valve so as to recover the excess air ratio based on the estimated excess air ratio, and observe The gain calculated based on the corrected engine load as a parameter is used to update the control signal for adjusting the fuel amount and to control the fuel adjusting means.
According to the first aspect of the present invention, the accuracy of the estimated excess air ratio is high because the excess air ratio is estimated based on the engine speed and the like that can be reliably and accurately measured even in an unsteady state. In addition, since the excess air ratio, which is important for understanding the engine state, is estimated and the opening of the exhaust valve is controlled, it becomes easier to maintain engine performance at maximum efficiency. Here, it is preferable that the excess air ratio is an accurately estimated true excess air ratio. The true excess air ratio is the scavenging efficiency of the engine, which is estimated based on a more detailed understanding of the engine's scavenging efficiency, based on data actually measured on the target engine and the results of computational fluid dynamics (CFD) calculations. Excess air ratio.

According to the second aspect of the present invention, when the excess air ratio is lower than the reference excess air ratio, the exhaust valve opening is controlled to advance the valve closing timing to recover the excess air ratio. and
According to the second aspect of the present invention, the excess air ratio can be effectively recovered, and the engine performance can be easily maintained at maximum efficiency.

The present invention according to claim 3 is characterized by further controlling the fuel adjustment means for adjusting the amount of fuel so as to restore the excess air ratio when the excess air ratio falls below the reference excess air ratio. .
According to the third aspect of the present invention, since the fuel control means is controlled in addition to the exhaust valve opening degree of the exhaust valve, it becomes easier to maintain the engine performance at the maximum efficiency.

In the engine control method using the engine state observation device corresponding to claim 4, the engine state observation is performed by estimating the engine state of a two-stroke engine equipped with an exhaust valve, a fuel control means, and a supercharger by an engine model. An engine control method for controlling using a device, comprising state parameters consisting of engine speed, supercharger speed of a supercharger, scavenging pressure, exhaust temperature, exhaust pressure, and engine load, and engine dynamics , the engine model parameters, and the fuel pump rack value of the fuel regulation means into a nonlinear state-space equation, which is the engine model that describes how the state parameters change with an update of the fuel pump rack value. On the other hand, the initial state values of the state parameters are set, and the engine speed in the engine that drives the propeller that causes the load fluctuation due to the disturbance in the actual sea area of the ship, the fuel amount adjusted by the fuel adjustment means, and the exhaust gas The lift amount or operation timing as the exhaust valve opening of the valve is detected as a sensor value and input to the engine state observer, and the initial state value of each state parameter and the fuel pump rack value as the sensor value in the nonlinear state space equation is used to estimate the state parameters, the estimated state parameters are observed and used as observation parameters, the observation parameters and the engine speed as sensor values are applied to the Kalman filter to correct the observation parameters, and the corrected observation parameters are the excess The amount of air to the engine is obtained based on the relational expression among the rotation speed of the feeder, the scavenging pressure, the exhaust temperature, the exhaust pressure, and the amount of air, and the amount of fuel as a sensor value , the amount of air to the engine, Excess air ratio is estimated based on exhaust valve opening or operation timing as a sensor value and scavenging efficiency of the engine obtained in advance. rate, it controls at least the exhaust valve opening degree of the exhaust valve so as to restore the excess air ratio based on the estimated excess air ratio, and based on the corrected engine load as an observation parameter The calculated gain is used to update a control signal for adjusting the amount of fuel to control the fuel adjusting means.
According to the fourth aspect of the present invention, it is possible to improve the estimation accuracy of the excess air ratio.

The present invention according to claim 5 uses the input initial state value, the engine speed detected and input at time k, the fuel pump rack value, and the exhaust valve opening or operation timing of the exhaust valve. , an engine state observer to estimate the excess air ratio and the load of the engine.
According to the fifth aspect of the present invention, it is possible to improve the accuracy of estimating the excess air ratio and the engine load.

In the present invention according to claim 6, the exhaust valve opening degree of the exhaust valve is controlled by the estimation result of the excess air ratio, and the engine speed detected and input at time k+1, the fuel pump rack value, and the exhaust In order to estimate the excess air ratio and the load of the engine with the engine state observer using the exhaust valve opening or operation timing of the valve, it is recommended to update the state parameters of the engine model at time k+1 with the corrected observation parameters. Characterized by
According to the sixth aspect of the present invention, the accuracy of estimating the excess air ratio and the engine load can be improved by using the latest observation parameters.

According to the seventh aspect of the present invention, when the estimation error of the state parameter estimation result deviates from a predetermined allowable range, the engine model parameters of the nonlinear state space equation as the engine model suitable for the specific engine are updated and updated. It is characterized by estimating the state parameters based on the engine model parameters obtained.
According to the seventh aspect of the present invention, it is possible to reduce the error and improve the accuracy of estimating the state parameters by using the engine model parameters adapted to the specific engine.

The present invention according to claim 8 is characterized in that an extended Kalman filter or an unscented Kalman filter is used for correcting the observation parameters in the engine state observer.
According to the eighth aspect of the present invention, by using the nonlinear Kalman filter, it is possible to improve the accuracy of estimating the excess air ratio and the engine load.

A ninth aspect of the present invention is characterized in that an extended Kalman filter or an unscented Kalman filter is selected based on the state of setting initial state values.
According to the ninth aspect of the present invention, the excess air ratio and the load of the engine can be accurately estimated according to the state of the engine model.

According to the tenth aspect of the present invention, an extended Kalman filter or an unscented Kalman filter is selected in advance and set in the engine state observer.
According to the tenth aspect of the present invention, the excess air ratio and the engine load can be quickly estimated.

An engine control program using an engine state observer corresponding to claim 11 is an engine state observer for estimating an engine state of a two-stroke engine having an exhaust valve, fuel control means, and a supercharger using an engine model. wherein the engine model consists of engine speed, supercharger speed of supercharger, scavenging pressure, exhaust temperature, exhaust pressure, and engine load; A non-linear state-space equation combining a non-linear function of engine dynamics, an engine model parameter, and a fuel pump rack value of a fuel regulator that describes how the state parameters change with an update of the fuel pump rack value. , engine speed, supercharger speed, scavenging air pressure in the engine that drives the propeller that causes load fluctuations due to disturbances in the actual sea area of the ship, which are input to the computer as the initial state values of the state parameters of the engine model; A state initial value acquisition step for acquiring the exhaust temperature, exhaust pressure, and engine load, and acquiring the engine speed at time k, the fuel pump rack value, and the exhaust valve opening or operation timing of the exhaust valve as sensor values. a sensor value acquisition step for estimating state parameters by applying the state initial values of the state parameters and the fuel pump rack value as the sensor value to the nonlinear state space equation; a state parameter estimation step for estimating the state parameters; Observation step that observes and uses as an observation parameter, an observation parameter correction step that corrects the observation parameter by applying the observation parameter and the engine speed as a sensor value to the Kalman filter, and an engine speed and fuel as the corrected observation parameter A fuel amount derivation step that obtains the fuel amount from the pump rack value, and the turbocharger rotation speed as corrected observation parameters, scavenging pressure, exhaust temperature, exhaust pressure, and air amount to the engine based on the relational expression An air amount derivation step for obtaining the air amount of , a fuel amount, an air amount to the engine, an exhaust valve opening or operation timing as a sensor value, and an engine scavenging efficiency obtained in advance to estimate an excess air ratio. To estimate the excess air ratio in the excess air ratio estimation step at predetermined time intervals by inputting the excess air ratio state estimation step and the fuel pump rack value as the sensor value obtained at time k+1 into the nonlinear spatial state equation. , the corrected observation parameters at time k+1 A parameter update step for updating the state parameters of the nonlinear state-space equation, and when the excess air ratio estimated based on the estimation result of the excess air ratio falls below the reference excess air ratio , the estimated excess air ratio is changed to Controls at least the opening of the exhaust valve so as to recover the excess air ratio based on the data, and updates the control signal that adjusts the fuel amount using the gain calculated based on the corrected engine load as the observed parameter and a control step of controlling the fuel adjusting means.
According to the eleventh aspect of the present invention, since the excess air ratio is estimated based on the initial state value and the engine speed that can be reliably and accurately measured even in an unsteady state, the accuracy of the estimated excess air ratio is is high. In addition, since the excess air ratio, which is important for understanding the engine state, is estimated to control the opening of the exhaust valve, it becomes easier to maintain engine performance at maximum efficiency even in an unsteady state.

The present invention according to claim 12 further comprises an engine model parameter update step for updating the engine model parameter when the estimation error of the state parameter estimation result in the state parameter estimation step deviates from a predetermined allowable range. It is characterized by estimating state parameters based on engine model parameters.
According to the twelfth aspect of the present invention, it is possible to reduce the error and improve the accuracy of estimating the state parameters by using the engine model parameters adapted to the specific engine.

According to a thirteenth aspect of the present invention, an extended Kalman filter or an unscented Kalman filter is used in the observation parameter correcting step.
According to the thirteenth aspect of the present invention, by using the nonlinear Kalman filter, it is possible to improve the accuracy of estimating the excess air ratio and the engine load.

According to a fourteenth aspect of the present invention, the method further comprises a selection step of selecting either the extended Kalman filter or the unscented Kalman filter based on the state of setting the initial state value.
According to the fourteenth aspect of the present invention, it is possible to accurately estimate the excess air ratio and the load of the engine according to the state of the engine model.

An engine control device using an engine state observer corresponding to claim 15 is a two-stroke engine equipped with an exhaust valve, fuel control means, and a supercharger using an engine control program using the engine state observer. An engine control device for controlling an engine , comprising a computer including an engine state monitor, engine speed, supercharger speed of a supercharger, scavenging pressure, exhaust temperature, exhaust pressure, and engine load. An engine model that combines state parameters, a non-linear function of engine dynamics, an engine model parameter, and a fuel pump rack value of the fuel regulator representing how the state parameters change with updates to the fuel pump rack values. input means for inputting initial state values of the state parameters; sensor value acquisition means for acquiring engine speed, fuel pump rack value, and exhaust valve opening as sensor values; and at least the exhaust valve of the exhaust valve and control means for controlling the degree of opening.
According to the fifteenth aspect of the present invention, the accuracy of the estimated excess air ratio is high because the excess air ratio is estimated based on the engine speed that can be reliably and accurately measured even in an unsteady state. In addition, since the excess air ratio, which is important for understanding the engine state, is estimated to control the opening of the exhaust valve, it becomes easier to maintain engine performance at maximum efficiency even in an unsteady state.

According to the engine control method using the engine state observer of the present invention, since the excess air ratio is estimated based on the engine speed etc. that can be reliably and accurately measured even in an unsteady state, the accuracy of the estimated excess air ratio is high. In addition, since the excess air ratio, which is important for understanding the engine state, is estimated and the opening of the exhaust valve is controlled, it becomes easier to maintain engine performance at maximum efficiency.

In addition, when the excess air ratio falls below the reference excess air ratio, control is performed to advance the valve closing timing as control of the opening of the exhaust valve to recover the excess air ratio. can be restored to normal, and it is easier to maintain engine performance at maximum efficiency.

Further, when the excess air ratio falls below the reference excess air ratio, when further controlling the fuel control means for adjusting the fuel amount so as to recover the excess air ratio, the exhaust valve opening degree of the exhaust valve In addition, it also controls the fuel adjustment means, further helping to maintain engine performance at maximum efficiency.

Further, according to the engine control method using the engine state monitor of the present invention, the fuel amount adjusted by the fuel adjustment means and the lift amount or operation timing as the exhaust valve opening degree of the exhaust valve are detected as sensor values. Since the excess air ratio is estimated by inputting it to the engine state observer, the accuracy of estimating the excess air ratio can be improved.

Also, using the input initial state value, the engine speed detected and input at time k, the fuel pump rack value, and the exhaust valve opening or operation timing of the exhaust valve, the engine state observer When estimating the excess air ratio and the engine load, the estimation accuracy of the excess air ratio and the engine load can be improved.

In addition, the exhaust valve opening of the exhaust valve is controlled by the estimation result of the excess air ratio, and the engine speed detected and input at time k + 1, the fuel pump rack value, and the exhaust valve opening of the exhaust valve or In order to estimate the excess air ratio and the load of the engine with the engine state observer using the operation timing, when updating with the corrected observed parameters as the state parameters of the engine model at time k+1, the latest observed parameters By using it, the accuracy of estimating the excess air ratio and the engine load can be improved.

In addition, when the estimation error of the state parameter estimation result deviates from the predetermined allowable range, the engine model parameters of the nonlinear state space equation as an engine model suitable for the specific engine are updated, and based on the updated engine model parameters When estimating the state parameters, it is possible to reduce errors and improve the accuracy of estimating the state parameters by using engine model parameters adapted to a specific engine.

In addition, when using an extended Kalman filter or an unscented Kalman filter to correct the observation parameters in the engine state monitor, a non-linear Kalman filter should be used to improve the accuracy of estimating the excess air ratio and engine load. can be done.

Further, when the extended Kalman filter or the unscented Kalman filter is selected based on the setting state of the initial state value, the excess air ratio and the engine load can be accurately estimated according to the state of the engine model. .

Further, when the extended Kalman filter or the unscented Kalman filter is selected in advance and set in the engine state observer, the excess air ratio and the load of the engine can be quickly estimated.

Further, according to the engine control program using the engine state observer of the present invention, the excess air ratio is estimated based on the initial state value and the engine speed that can be reliably and accurately measured even in an unsteady state. The accuracy of the excess air ratio is high. In addition, since the excess air ratio, which is important for understanding the engine state, is estimated to control the opening of the exhaust valve, it becomes easier to maintain engine performance at maximum efficiency even in an unsteady state.

The engine model parameter update step of updating the engine model parameter when the estimation error of the state parameter estimation result in the state parameter estimation step deviates from a predetermined allowable range, wherein the state parameter is updated based on the updated engine model parameter. When estimating parameters, it is possible to reduce errors and improve the accuracy of estimating state parameters by using engine model parameters adapted to a specific engine.

Further, in the observation parameter correction step, when using an extended Kalman filter or an unscented Kalman filter, using a non-linear Kalman filter can improve the accuracy of estimating the excess air ratio and the engine load.

In addition, when further comprising a selection step of selecting an extended Kalman filter or an unscented Kalman filter based on the setting state of the state initial value, the excess air ratio and the load of the engine are estimated according to the state of the engine model. can be done accurately.

Further, according to the engine control device using the engine state observer of the present invention, since the excess air ratio is estimated based on the engine speed that can be reliably and accurately measured even in an unsteady state, the estimated excess air ratio is High accuracy. In addition, since the excess air ratio, which is important for understanding the engine state, is estimated to control the opening of the exhaust valve, it becomes easier to maintain engine performance at maximum efficiency even in an unsteady state.

1 is a conceptual diagram of an engine control system using an engine state monitor according to the present embodiment; FIG. Conceptual diagram of control using the same engine state monitor Configuration diagram showing the configuration and relationship of the engine, control unit and load Functional block diagram of the exhaust valve control system A diagram showing the relationship between the opening degree of the exhaust valve and the excess air ratio Flowchart showing how to set the engine model parameters and select the Kalman filter Flowchart showing a method for estimating the state of the same engine A diagram showing the estimation error of the same engine state

An engine control method, an engine control program, and an engine control device using an engine state observer according to embodiments of the present invention will be described below.

FIG. 1 is a conceptual diagram of an engine control system using an engine state observer according to this embodiment.
The engine control device 10 is a propulsion plant simulator that incorporates each module of a propeller model and an engine model that take into account disturbances (Actual Sea Conditions) representing actual sea conditions such as wave and wind conditions, and is a so-called virtual plant. Plant), compare it with the actual plant (Real Plant), modify the engine model parameters offline or online, improve the accuracy of the simulator, and perform detailed control of the engine.
The engine control system 10 utilizes an engine control program with an engine condition observer 15 to control an engine having exhaust valves and fuel control means. The engine is mounted on a ship and drives a propeller that propels the ship as a load.
The engine control device 10 includes a computer 11 including an engine state observer 15, an input means 12 for setting an initial state value including the engine speed, an engine speed, a fuel adjustment amount by a fuel adjustment means, and an exhaust valve. It comprises a sensor value acquisition means 13 for acquiring the lift amount and the operation timing of the exhaust valve, and a control output means 14 for controlling the exhaust valve and the fuel adjustment means (fuel pump rack). The input means 12 is a control panel, mouse, keyboard, touch panel, or the like. As for the exhaust valve, the sensor value acquisition means 13 can acquire the valve closing timing, the valve opening timing, and the valve lift amount singly or in combination.

FIG. 2 is a conceptual diagram of control using the engine state observer according to this embodiment.
The engine control device 10 acquires the rotational speed _ne of the engine 1 that drives the propeller 2 by means of a sensor value acquisition means 13 such as a detector, and inputs it to the engine state observer 15 . The engine state observer 15 estimates the excess air ratio λ and the engine load _qp as the engine state from an engine model using the input rotational speed _ne . Then, the engine control device 10 calculates the optimum gain and sends control update signals for the exhaust valve opening EVC (valve closing timing) and the fuel pump rack _hp . The engine control device 10 adjusts the exhaust valve opening EVC and the fuel pump rack _hp by the control output means 14 based on the transmitted signal. The exhaust valve opening degree EVC may be adjusted not only by the closing timing of the exhaust valve, but also by the opening timing, the valve lift amount, or a combination thereof. Further, the adjustment of the fuel adjustment means may be the timing of the fuel pump, the electronic governor, the fuel adjustment mechanism, etc., in addition to the fuel pump rack _hp .
Here, in estimating the excess air ratio λ, the scavenging efficiency of the engine 1 obtained in advance by experiments, CFD simulations, or the like is used. In particular, during the scavenging process of a two-stroke engine, a portion of the total charge air supplied passes through the cylinder, and the remaining charge air remains in the cylinder after scavenging ends. At this time, residual exhaust gas consisting of combustion gas from the previous cycle exists in the cylinder, so the total amount of gas in the cylinder after scavenging is the sum of the residual supply air and the residual exhaust gas. The scavenging efficiency is a ratio of the mass of the residual supply air after completion of scavenging to the total amount of gas in the cylinder, and is a value that indicates the quality of the scavenging action. The scavenging efficiency represents the air supply concentration in the cylinder, and is a value that is directly linked to the engine output. Therefore, unless the correct scavenging efficiency of the engine 1 is known, the true excess air ratio λ cannot be derived, and the engine performance cannot be truly maintained at the maximum efficiency based on the excess air ratio λ.
In this way, at least the rotational speed _ne of the engine 1 is detected and input to the engine state observer 15, and the engine state observer 15 detects the true excess air ratio λ based on the scavenging efficiency and the engine load q based on the scavenging efficiency as the engine state. _p is estimated, and based on the estimated true excess air ratio λ, the exhaust valve and the fuel adjustment means are controlled as controlled objects. Since the excess air ratio λ is estimated based on the rpm n _e of the engine 1 that can be reliably and accurately measured, and based on the scavenging efficiency, the number of parameters used for estimation is reduced, while estimating the excess air ratio λ with high accuracy. can. In addition, since the exhaust valve and the fuel adjustment means are controlled by estimating the excess air ratio λ, which is important for grasping the engine state, the performance of the engine 1 mounted on the ship can be maintained at the maximum efficiency and it becomes easy to operate. .
At least one of the lift amount (opening degree) or operation timing of the exhaust valve and the fuel adjustment amount by the fuel adjustment means are acquired by the sensor value acquisition means 13, input to the engine state observer 15, and the excess air ratio By using it for estimating the engine state including λ, the estimation accuracy of the engine state can be improved.
In addition, the engine state observer 15 estimates the engine state in consideration of the state of the propeller 2 by using the propeller model, so that the estimation accuracy of the engine state can be further improved.

FIG. 3 is a configuration diagram showing the configuration and relationship of the engine, control unit, and load.
The engine 1 is assumed to be a two-stroke diesel engine, and includes an engine body 3, a supercharger 4, an air supply pipe, an intercooler 5, a scavenging receiver 20, an exhaust valve 6, an exhaust receiver 7, an exhaust pipe, and a fuel control means 16 ( A fuel pump 16a, an electronic governor 16b, a fuel control mechanism 16c) and a controller 17 (exhaust valve timing changing mechanism 17a, exhaust valve driving pump 17b).

The engine body 3 includes a cylinder 3a, a piston 3b, a crank 3c, and the like. In the engine body 3, air is supplied to and scavenged from the cylinder 3a in accordance with the reciprocating motion of the piston 3b within the cylinder 3a. Further, fuel is supplied into the cylinder 3a by the fuel adjusting means 16, and the mixture of fuel and air is ignited, combusted and exploded, and the resulting energy drives the piston 3b. A driving force applied to the piston 3b is transmitted to the load via the crank 3c. The main load in the present embodiment is the propeller 2 for propulsion of the ship, and the load of the propeller 2 is changed by disturbance due to waves and winds and changes in ship speed, and the engine 1 is in an unsteady state.

The supercharger 4 includes a compressor C and a turbine T. In the turbocharger 4, the energy (temperature and pressure) of the exhaust gas from the engine body 3 is used to rotate the turbine T at high speed, and the rotational force of the turbocharger 4 drives the compressor C, thereby compressing the air into the engine body 3. into the cylinder 3a. That is, the supercharger 4 feeds compressed air into the engine body 3 and sucks and explodes an air-fuel mixture that exceeds the original air supply amount of the engine 1, thereby giving an output exceeding the apparent displacement.

Air compressed in the supercharger 4 is sent to the air supply pipe via a diffuser or the like. An intercooler 5 is provided in the air supply pipe. The intercooler 5 performs intermediate cooling of the compressed air. The compressed air that has passed through the intercooler 5 is sent to the scavenging receiver 20 and stored. Compressed air stored in the scavenging receiver 20 is sent into the cylinder 3a of the engine body 3 through a scavenging port that is open when the piston 3b of the engine body 3 is near the bottom dead center. The fuel adjusting means 16 comprises a fuel pump 16a, an electronic governor 16b and a fuel adjusting mechanism 16c. The electronic governor 16b receives a rotational speed signal _Ne indicating the rotational speed of the crank 3c and controls the drive timing of the fuel pump 16a. The fuel pump 16a injects fuel into the cylinder 3a at desired timing under the control of the electronic governor 16b. Fuel is supplied from the fuel adjustment means 16 into the cylinder 3a of the engine main body 3 to form an air-fuel mixture, which is compressed by the piston 3b to burn the air-fuel mixture. Driving force is applied to the piston 3b by combustion.

Exhaust gas generated by combustion in the engine body 3 is scavenged by compressed air stored in the scavenging receiver 20 when the exhaust valve 6 is opened and sent to the exhaust receiver 7 . The exhaust gas stored in the exhaust receiver 7 is guided to the turbine T of the turbocharger 4 and is exhausted after giving rotational force.

In the present embodiment, the control unit 18 controls the valve opening timing for changing the exhaust valve 6 from the closed state to the open state and the valve closing timing for changing the exhaust valve 6 from the open state to the closed state. Specifically, the control unit 18 functions as an exhaust valve timing control device, and controls the operation timing and opening degree (lift amount) of the exhaust valve 6 by controlling the exhaust valve timing changing mechanism 17a. The exhaust valve timing changing mechanism 17a uses the hydraulic pressure generated by the exhaust valve drive pump 17b to adjust the pressure for opening the exhaust valve 6 by an electromagnetic relief valve provided in the hydraulic actuator that pushes the exhaust valve 6. Control valve 6; Control of the exhaust valve 6 will be described later. The exhaust valve 6 may be controlled by only the operation timing, only the opening (lift amount), or a combination thereof. It is preferable because it can be done.

Further, in the present embodiment, a scavenging bypass pipe 19 is connected to the scavenging receiver 20 . The scavenging bypass pipe 19 is provided with a flow rate sensor 19a and an extraction valve 19b. By opening the take-out valve 19b, part of the compressed air sent to the scavenging receiver 20 is sent to a supply pipe (not shown) for air lubrication. On the other hand, by closing the take-out valve 19b, the compressed air sent to the scavenging receiver 20 is not sent to the supply pipe. The opening of the take-out valve 19b is controlled by the controller 18 using the signal from the flow rate sensor 19a.

FIG. 4 shows a functional block diagram of the exhaust valve control system. The ship in this embodiment is equipped with a frictional resistance reduction device that extracts pressurized air (scavenging air) from the vicinity of the supercharger 4 and ejects air bubbles around the hull to lubricate the ship and reduce the frictional resistance of the ship. ing. Taking out scavenging air during this air lubrication also falls under the unsteady state.
The engine state observer 15 detects the rotation speed n _e of the engine 1, the fuel pump rack h _p and the exhaust valve opening EVC from the rotation speed sensor 13a, the fuel adjustment amount sensor 13b and the exhaust valve sensor 13c, which are the sensor value acquisition means 13, respectively. Get information about The rotation speed sensor 13a is provided on the engine body 3, the fuel adjustment amount sensor 13b is provided on the fuel adjustment means 16, and the exhaust valve sensor 13c is provided on the exhaust valve 6 or the exhaust valve timing changing mechanism 17a. The rotation speed sensor 13a detects the rotation speed _ne of the engine 1, the fuel adjustment amount sensor 13b detects the fuel pump rack _hp , and the exhaust valve sensor 13c detects the exhaust valve opening EVC.
The engine state observer 15 calculates the excess air ratio λ and the load _qp of the engine 1 as the engine state from an engine model using the input engine 1 speed n _e , fuel pump rack _hp and exhaust valve opening EVC. After estimating and calculating the optimum gain, control update signals for the exhaust valve opening EVC and the fuel pump rack _hp are sent to the control output means 14 .
The control output means 14 sends a control setting signal for the exhaust valve opening degree EVC to the control section (exhaust valve timing control device) 18 . The control unit (exhaust valve timing control device) 18 that receives the control setting signal for the exhaust valve opening degree EVC controls the timing and opening degree (lift amount) of opening and closing the exhaust valve 6 . Specifically, the operation timing and opening degree (lift amount) of the exhaust valve 6 are adjusted by the exhaust valve timing changing mechanism 17a. The exhaust valve timing changing mechanism 17a controls an electromagnetic relief valve provided in a hydraulic actuator that pushes the exhaust valve 6 according to a control signal from a control unit (exhaust valve timing control device) 18, thereby is adjusted to adjust the operating timing and the degree of opening (lift amount) of the exhaust valve 6 .
The control output means 14 also sends a control setting signal for the fuel pump rack _hp to the fuel adjustment means 16 . Upon receiving the control setting signal for the fuel pump rack _hp , the fuel adjusting means 16 adjusts the amount of fuel according to the control setting signal.

In this embodiment, at least the exhaust valve 6 is controlled according to the state of taking out the taken-out air for air lubrication as an unsteady state. The amount of scavenging extraction air is varied in relation to the amount of air produced as bubbles required for air lubrication. That is, the amount of take-out air (scavenging air) taken out from the scavenging-air bypass pipe 19 via the take-out valve 19b is controlled.

The take-out ratio of the taken-out air is controlled by the take-out valve 19b. Here, the amount of air taken out from the scavenging air is detected by the flow rate sensor _19a provided in the scavenging bypass pipe 19 shown in FIG. , the extraction rate of the extracted air can be determined. Instead of using the flow rate sensor 19a, the amount of air to be taken out may be obtained based on the degree of opening (displacement) of the take-out valve 19b.

In addition, the take-out ratio refers to the ratio of the amount of pressurized air (scavenging air) supplied from the supercharger 4 to the take-out air, for example. At this time, the amount is preferably the mass flow rate, and even if other ratios are used, it is preferable that the amount of scavenging air supplied to the engine body 3 is ensured. In actual control, the amount of scavenging air supplied to the engine body 3 may be directly measured by the flow rate, or may be substituted by the scavenging pressure or the like.

On the other hand, the scavenging pressure in the engine 1 decreases according to the extraction ratio of the extracted air, and the performance of the engine 1 deteriorates. Also, the amount of harmful substances in the exhaust gas may increase. Therefore, the control unit 18 first controls the exhaust valve 6 of the engine 1 according to the amount of air taken out. Specifically, the control unit 18 controls the closing timing of the exhaust valve 6 according to the intake air. Thereby, the control unit 18 functions as a timing control means.
The engine state observer 15 estimates the excess air ratio λ and the load _qp of the engine 1 as the engine state from the engine model using the rotation speed n _e of the engine 1, the fuel pump rack h _p and the exhaust valve opening EVC, An optimum gain suitable for taking out air is calculated, and control setting signals for the exhaust valve opening EVC and the fuel pump rack _hp are sent to the control output means 14 .
The previously controlled closing timing of the exhaust valve 6 is corrected according to the control setting signal if there is a difference from the closing timing of the exhaust valve opening degree EVC, which is the control setting signal of the engine state observer 15 .
In the above example, scavenging air is taken out as pressurized air for air lubrication. The exhaust may be taken out and used. It is also possible to take out and use a combination of scavenging, supplying and exhausting air.

FIG. 5 is a diagram showing the relationship between the opening degree of the exhaust valve and the excess air ratio. FIG. 5(a) shows valve closing timings of the initial exhaust valve opening (EVC_0), the first exhaust valve opening (EVC_1), and the second exhaust valve opening (EVC_2).
The excess air ratio λ decreases due to unsteady times when the wave and wind conditions in the actual sea area are bad, the performance deterioration of the turbocharger, and the above-mentioned scavenging air extraction state, etc., but the exhaust valve opening EVC is the initial state. With (EVC_0) as it is, the original optimal excess air ratio λ cannot be restored. Therefore, as shown in FIG. 5B, the engine control device 10 changes the exhaust valve opening degree EVC from the first exhaust valve opening degree (EVC_1 ), or to the second exhaust valve opening (EVC_2) to restore the original optimal excess air ratio λ. This allows engine performance to be maintained at maximum efficiency.

Next, a method for estimating the engine state in the engine control program will be described with reference to FIGS. 6 to 8. FIG.
In this embodiment, an extended Kalman filter (EKF) or an unscented Kalman filter (UKF) is used for estimating the engine state in the engine state observer 15 .

ここで、λは空気過剰率、Ｇ_ａは空気量、Ｇ_ｆは燃料量、ＥＶＣは排気弁開度、ｎ_ｔｃは過給機回転数、ｐ_ｓは掃気圧力、Ｔ_ｅは排気温度、Ｐ_eは排気圧力、ｎ_ｅはエンジン回転数、ｈ_ｐは燃料ポンプラックである。 The following expression (1) is a nonlinear relational expression between the engine state parameter and the excess air ratio λ.

where, λ is the excess air ratio, _Ga is the air amount, _Gf is the fuel amount, EVC is the exhaust valve opening, _ntc is the turbocharger speed, _ps is the scavenging pressure, _Te is the exhaust temperature, P _e is the exhaust pressure, _ne is the engine speed, and _hp is the fuel pump rack.

ここで、Ａ_ｉ，Ｂ_ｉはエンジンダイナミクスの非線形関数、Ｓ_Ａｉ，Ｓ_Ｂｉは特定のエンジンに対するエンジンモデルパラメータの設定値である。 Also, the following equation (2) represents the nonlinear state space equation of the engine dynamic model. State parameters of engine speed n _e , supercharger speed n _tc , scavenging air pressure p _s , exhaust temperature T _e , and exhaust pressure P _e are changed by control update of fuel pump rack h _p and engine load q _p . We show the state-space equation of how

where A _i , B _i are non-linear functions of engine dynamics and S _Ai , S _Bi are engine model parameter settings for a particular engine.

Also, the following equation (3) represents the nonlinear state-space equation of the engine dynamic model when the engine load _qp is unknown, and is for the unscented Kalman filter (UKF).

Moreover, the following formula (4) is an LTI (Linear time invariant) model for an extended Kalman filter (EKF). Using this linear model can speed up the computation.

FIG. 6 is a flow chart showing a method of setting engine model parameters and selecting a Kalman filter.
First, by setting engine model parameters S _An and S _Bn for a specific engine, a non-linear model suitable for the specific engine is created (non-linear model creation step S1).
After the nonlinear model creation step S1, it is determined whether or not the created model is uncertain (determination step S2).
If it is determined in decision step S2 that the created model is uncertain, an unscented Kalman filter (UKF) using equation (3) is selected (UKF selection step S3).
If it is determined in decision step S2 that the created model is reliable, an extended Kalman filter (EKF) using equation (4) is selected (EKF selection step S4).
Thus, an algorithm is pre-created off-line that selects between the unscented Kalman filter (UKF) and the extended Kalman filter (EKF) depending on whether the engine model parameters are uncertain.
As shown in FIG. 1, the set engine model parameters can be compared with the actual plant and updated off-line as needed.
These offline steps and updates can also be done online.

FIG. 7 is a flow chart showing a method for estimating the engine state. In the flow chart of FIG. 7, the engine condition is estimated online in real time every predetermined time (for example, 200 Hz).
First, the engine speed n _e , supercharger speed n _tc , scavenging pressure p _s , exhaust temperature T _e , engine load q _p , and exhaust pressure P _e are obtained as initial state values (state initial value obtaining step S10). By acquiring and setting the state initial value, the estimation accuracy of the engine state can be improved.
After the state initial value acquisition step S10, the engine speed n _e (k), the fuel pump rack h _p (k), and the exhaust valve opening EVC(k) at time k are acquired from the sensor value acquisition means 13. (Sensor value acquisition step S11). Alternatively, only the engine speed n _e (k) may be acquired.
After the sensor value acquisition step S11, the engine speed n _e (k), the fuel pump rack h _p (k), and the exhaust valve opening EVC(k) at the time k acquired in the sensor value acquisition step S11, and the state Based on the state initial values acquired in the initial value acquisition step S10, the engine state observer 15 estimates state parameters as the engine state, observes them, corrects them, and estimates the excess air ratio λ (engine state estimation step S12). Observation parameters to be observed are engine speed n _e , supercharger speed n _tc , scavenging pressure p _s , exhaust temperature T _e , engine load q _p , and exhaust pressure P _e . By using an extended Kalman filter (EKF) or an unscented Kalman filter (UKF) for estimating the engine state in the engine state observer 15, the estimation accuracy of the engine state can be improved. Which one to use follows the selection procedure described with reference to FIG. An extended Kalman filter (EKF) or an unscented Kalman filter (UKF) may be selected in advance and set in the engine state observer 15 . In this case, the estimation of the engine state can be performed more quickly.

After the engine state estimation step S12, the fuel pump rack _hp and the exhaust valve opening degree EVC are used as inputs for control based on the estimated conditions to control the fuel adjustment means 16 and the exhaust valve (control step S13). This allows engine performance to be maintained at maximum efficiency.
After control step S13, the engine speed n _e (k+1), the fuel pump rack _hp (k+1), and the exhaust valve opening EVC (k+1) at time k+1, which is the next predetermined time after time k, are obtained ( Next time sensor value acquisition step S14), and the process returns to engine state estimation step S12.
After correcting the observation parameters in the engine state estimation step S12, the state parameters of the engine model are updated based on the correction result (observation parameter update step S15).
In this manner, the engine state observer 15 repeatedly estimates the engine state and updates the state parameters of the engine model.

Also, FIG. 8 is a diagram showing an estimation error of the engine state. In FIG. 8, the vertical axis is the error, the horizontal axis is the time, the dotted line indicates the allowable range of the engine state estimation error, and the solid line indicates the estimated error value of the engine state.
The engine control device 10 tracks the estimation error of the engine state by the engine state observer 15, and updates the engine model parameters when it deviates from a predetermined allowable range (engine model parameter update step S16).
Then, based on the updated engine model parameters, the engine state is estimated in the engine state estimation step S12. As a result, the error in the engine model parameters can be reduced, the error estimation accuracy of the engine state can be increased, and the reliability can be improved.
There are various methods for updating the engine model parameters, such as updating when they deviate from a predetermined allowable range multiple times, or updating when a predetermined condition is reached by integrating the error over time. can be adopted.

As described above, as a means of solving the problems of the conventional control method using closed and open loop control, the present embodiment does not use many measurement sensors for control, but rather detects the state of the engine model. We use an observer that uses a non-linear Kalman filter, the unscented Kalman filter (UKF), or the extended Kalman filter (EKF), which is called a soft sensor.
It is significant that this mathematical model consists of two parts. a) a non-linear model that fits a particular engine, and b) a linear model that is fully bound to that non-linear model. This allows the engine state observer 15 with an unscented Kalman filter (UKF) or an engine state observer 15 with an extended Kalman filter (EKF) to be used to effectively track the non-linear processes of the engine. becomes. Furthermore, it becomes possible to estimate the state inside the engine that cannot be measured normally. In particular, the true excess air ratio λ and the engine load q _p (propeller load), which are important for engine performance, can be estimated and used for control input. As a result, it is possible not only to estimate the current operating condition of the engine, but also to accurately predict the engine condition in the near future, thereby enabling optimal and safe driving.
The engine state parameter may be any other parameter or combination as long as the excess air ratio λ can be approximately accurately estimated. You can choose.

INDUSTRIAL APPLICABILITY The engine control method, engine control program, and engine control device using the engine state observer of the present invention can be suitably used for controlling the engine of a ship propulsion plant. In particular, the excess air ratio in the cylinders of a two-stroke engine can be optimally maintained, and the engine performance can be maintained at maximum efficiency. It can also be used to control any engine equipped with exhaust valves and fuel adjustment means that require control of at least excess air ratio. For example, it can be used to control a gas engine that requires finer control.

1 engine 2 propeller 6 exhaust valve 10 engine control device 11 computer 12 input means 13 sensor value acquisition means 14 control output means 15 engine state observer 16 fuel adjustment means S3, S4 selection step S10 state initial value acquisition step S11 sensor value acquisition step S12 Engine state estimation step S13 Control step S15 Observation parameter update step λ Excess air ratio q _p Engine load n _e Engine speed

Claims (15)

An engine control method for controlling a two-stroke engine equipped with an exhaust valve, fuel control means, and a supercharger using an engine state observer for estimating the engine state from an engine model, comprising:
State parameters consisting of the engine speed, the supercharger speed of the supercharger, the scavenging pressure, the exhaust temperature, the exhaust pressure, and the load of the engine, a nonlinear function of engine dynamics, and an engine model parameter; For a nonlinear state-space equation of the engine model that represents how the state parameter changes with an update of the fuel pump rack value in combination with the fuel pump rack value of the fuel adjustment means, the state parameter set the initial state values for each of
Detecting, as sensor values, the number of rotations of the engine that drives the propeller that causes load fluctuations due to disturbances in the actual sea area of the ship, the fuel pump rack value, and the exhaust valve opening or operation timing of the exhaust valve. input into the engine condition observer;
estimating the state parameters using the initial state values and the fuel pump rack values of the state parameters in the nonlinear state space equation, observing the estimated state parameters and using them as observation parameters;
Applying a Kalman filter to the observed parameter and the rotation speed of the engine as the sensor value to correct the observed parameter,
obtaining a fuel amount from the engine speed as the corrected observation parameter and the fuel pump rack value as the sensor value;
Obtaining the air amount to the engine based on a relational expression among the supercharger rotation speed, the scavenging pressure, the exhaust temperature, the exhaust pressure, and the air amount as the corrected observation parameters,
estimating an excess air ratio from the fuel amount, the air amount to the engine, the exhaust valve opening degree or the operation timing as the sensor value, and the scavenging efficiency of the engine obtained in advance;
When the excess air ratio estimated by the engine condition observer at predetermined intervals falls below the reference excess air ratio, the excess air ratio is restored based on the estimated excess air ratio. and controlling at least the exhaust valve opening degree of the exhaust valve, and updating the control signal for adjusting the fuel amount using the gain calculated based on the corrected engine load as the observation parameter, and the fuel adjustment An engine control method using an engine state observer, characterized by controlling means. 2. When the excess air ratio becomes lower than the reference excess air ratio, the exhaust valve opening degree is controlled to advance the valve closing timing to restore the excess air ratio. 2. An engine control method using the engine state observer according to 1. 2. When the excess air ratio falls below the reference excess air ratio, the fuel adjusting means for adjusting the fuel amount to restore the excess air ratio is further controlled. 3. An engine control method using the engine state observer according to claim 2. An engine control method for controlling a two-stroke engine equipped with an exhaust valve, fuel control means, and a supercharger using an engine state observer for estimating the engine state from an engine model, comprising:
State parameters consisting of the engine speed, the supercharger speed of the supercharger, the scavenging pressure, the exhaust temperature, the exhaust pressure, and the load of the engine, a nonlinear function of engine dynamics, and an engine model parameter; For a nonlinear state-space equation of the engine model that represents how the state parameter changes with an update of the fuel pump rack value in combination with the fuel pump rack value of the fuel adjustment means, the state parameter set the initial state values for each of
The rotation speed of the engine that drives the propeller that causes load fluctuations due to disturbances in the actual sea area of the ship, the fuel amount adjusted by the fuel adjustment means, and the lift amount as the exhaust valve opening of the exhaust valve, or Detecting the operation timing as a sensor value and inputting it to the engine state observer,
estimating the state parameters using the initial state values and the fuel pump rack values of the state parameters in the nonlinear state space equation, observing the estimated state parameters and using them as observation parameters;
Applying a Kalman filter to the observed parameter and the rotation speed of the engine as the sensor value to correct the observed parameter,
Obtaining the air amount to the engine based on a relational expression among the supercharger rotation speed, the scavenging pressure, the exhaust temperature, the exhaust pressure, and the air amount as the corrected observation parameters,
An excess air ratio is estimated from the fuel amount as the sensor value , the air amount to the engine, the exhaust valve opening degree or the operation timing as the sensor value, and the scavenging efficiency of the engine acquired in advance. death,
When the excess air ratio estimated by the engine condition observer at predetermined intervals falls below the reference excess air ratio, the excess air ratio is restored based on the estimated excess air ratio. and controlling at least the exhaust valve opening degree of the exhaust valve, and updating the control signal for adjusting the fuel amount using the gain calculated based on the corrected engine load as the observation parameter, and the fuel adjustment An engine control method using an engine state observer, characterized by controlling means. Using the input initial state value, the engine speed detected and input at time k, the fuel pump rack value, and the exhaust valve opening or operation timing of the exhaust valve, the engine 5. An engine control method using an engine state observer according to any one of claims 1 to 4, wherein the state observer estimates the excess air ratio and the load of the engine. The exhaust valve opening degree of the exhaust valve is controlled based on the estimation result of the excess air ratio, and the rotational speed of the engine detected and input at time k+1, the fuel pump rack value, and the exhaust valve The observation corrected as the state parameter at the time k+1 of the engine model in order to estimate the excess air ratio and the load of the engine with the engine state observer using the exhaust valve opening or the operation timing. 6. An engine control method using an engine state observer according to claim 5, wherein the parameter is updated. updating the engine model parameters of the non-linear state space equation as the engine model suitable for the specific engine when the estimation error of the state parameter estimation result deviates from a predetermined allowable range; and updating the engine model. 7. An engine control method using an engine state observer according to any one of claims 1 to 6, wherein the state parameter is estimated based on the parameter. The engine state observer according to any one of claims 1 to 7, wherein an extended Kalman filter or an unscented Kalman filter is used to correct the observation parameters in the engine state observer. Engine control method used. 9. The engine control method using an engine state observer according to claim 8, wherein the extended Kalman filter or the unscented Kalman filter is selected based on the setting state of the initial state value. 9. An engine control method using an engine state observer according to claim 8, wherein said extended Kalman filter or said unscented Kalman filter is selected in advance and set in said engine state observer. An engine control program for controlling a two-stroke engine equipped with an exhaust valve, fuel control means and a supercharger using an engine state observer for estimating the engine state from an engine model,
The engine model includes state parameters consisting of the engine speed, the supercharger speed of the supercharger, the scavenging pressure, the exhaust temperature, the exhaust pressure, and the load of the engine, and a nonlinear function of engine dynamics; a non-linear state-space equation combining an engine model parameter and a fuel pump rack value of the fuel modulating means representing how the state parameter changes with an update of the fuel pump rack value;
to the computer,
The engine speed, the supercharger speed, and the scavenging in the engine that drives the propeller that causes load fluctuations due to disturbances in the actual sea area of the ship that are input as the state initial values of the state parameters of the engine model. a state initial value acquisition step of acquiring the pressure, the exhaust temperature, the exhaust pressure, and the load of the engine;
a sensor value acquisition step of acquiring, as sensor values, the number of rotations of the engine at time k, the fuel pump rack value, and the exhaust valve opening or operation timing of the exhaust valve;
a state parameter estimation step of applying the state initial values for each of the state parameters and the fuel pump rack value as the sensor value to the nonlinear state-space equation to estimate the state parameters;
an observation step of observing the estimated state parameter and using it as an observation parameter;
an observation parameter correcting step of applying a Kalman filter to the observation parameter and the rotation speed of the engine as the sensor value to correct the observation parameter;
a fuel amount derivation step of obtaining a fuel amount from the engine speed and the fuel pump rack value as the corrected observation parameters;
Air for determining the amount of air to the engine based on a relational expression among the supercharger rotation speed, the scavenging pressure, the exhaust temperature, the exhaust pressure, and the air amount as the corrected observation parameters. a quantity derivation step;
Excess air ratio for estimating the excess air ratio from the fuel amount, the air amount to the engine, the exhaust valve opening degree or the operation timing as the sensor value, and the scavenging efficiency of the engine acquired in advance. an estimation step;
The fuel pump rack value as the sensor value acquired at time k+1 is input to the nonlinear space state equation, and corrected to estimate the excess air ratio in the excess air ratio estimation step every predetermined time. a parameter update step of updating the observation parameter as the state parameter of the nonlinear state-space equation at time k+1;
recovering the excess air ratio based on the estimated excess air ratio when the excess air ratio estimated based on the estimation result of the excess air ratio falls below the reference excess air ratio ; The fuel adjustment means controls at least the opening degree of the exhaust valve and updates a control signal for adjusting the fuel amount using a gain calculated based on the corrected engine load as the observation parameter. An engine control program using an engine state observer, characterized by executing a control step for controlling the further comprising an engine model parameter update step of updating the engine model parameter when an estimation error of the state parameter estimation result in the state parameter estimation step deviates from a predetermined allowable range, and based on the updated engine model parameter, 12. The engine control program using the engine state observer according to claim 11, wherein the state parameter is estimated by using the engine state observer. 13. The engine control program using the engine state observer according to claim 11, wherein an extended Kalman filter or an unscented Kalman filter is used in said observation parameter correcting step. 14. The engine control program using the engine state observer according to claim 13, further comprising a selection step of selecting said extended Kalman filter or said unscented Kalman filter based on the setting state of said initial state value. . A two-stroke engine equipped with an exhaust valve, fuel control means and a supercharger is controlled using an engine control program using the engine state monitor according to any one of claims 11 to 14. An engine control device comprising a computer including the engine state monitor, the rotation speed of the engine, the supercharger rotation speed of the supercharger, the scavenging pressure, the exhaust temperature, the exhaust pressure, and the load of the engine. A combination of a state parameter, a non-linear function of engine dynamics, an engine model parameter, and a fuel pump rack value of the fuel adjustment means to determine how the state parameter changes with an update of the fuel pump rack value. Input means for inputting initial state values of the state parameters of the engine model represented ; sensor value acquisition for acquiring the rotational speed of the engine, the fuel pump rack value , and the degree of opening of the exhaust valve as sensor values; and control means for controlling at least the degree of opening of the exhaust valve of the exhaust valve.

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