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エンジン スピード モデルの線形化

この例では、エンジン スピード モデルを線形化する方法を説明します。

モデルを開きます。

```scdspeed
```

この例では、出力エンジン スピードの線形モデルと入力間の線形モデル、点火進角、およびスロットル角を生成します。FINDOP コマンドは、2000 rpm、3000 rpm、および 4000 rpm の定常状態条件で操作点を計算します。

```opspec = operspec('scdspeed')
```
``` Operating Specification for the Model scdspeed.
(Time-Varying Components Evaluated at time t=0)

States:
----------
(1.) scdspeed/Throttle & Manifold/Intake Manifold/p0 = 0.543 bar
spec:  dx = 0,  initial guess:         0.543
(2.) scdspeed/Vehicle Dynamics/w = T//J w0 = 209 rad//s
spec:  dx = 0,  initial guess:           209

Inputs:
----------
(1.) scdspeed/Throttle  perturbation
initial guess: 0

Outputs: None
----------

```

```opspec = addoutputspec(opspec,'scdspeed/rad//s to rpm',1);
```

```opspec.Output.Known = 1;
opspec.Outputs.y = 2000;
```

この仕様を満たす操作点を検索します。

```op(1) = findop('scdspeed',opspec);
```
``` Operating Point Search Report:
---------------------------------

Operating Report for the Model scdspeed.
(Time-Varying Components Evaluated at time t=0)

Operating point specifications were successfully met.
States:
----------
(1.) scdspeed/Throttle & Manifold/Intake Manifold/p0 = 0.543 bar
x:         0.544      dx:      2.66e-13 (0)
(2.) scdspeed/Vehicle Dynamics/w = T//J w0 = 209 rad//s
x:           209      dx:     -8.48e-12 (0)

Inputs:
----------
(1.) scdspeed/Throttle  perturbation
u:       0.00382    [-Inf Inf]

Outputs:
----------
y:         2e+03    (2e+03)

```

```opspec.Outputs.y = 3000;
op(2) = findop('scdspeed',opspec);
opspec.Outputs.y = 4000;
op(3) = findop('scdspeed',opspec);
```
``` Operating Point Search Report:
---------------------------------

Operating Report for the Model scdspeed.
(Time-Varying Components Evaluated at time t=0)

Operating point specifications were successfully met.
States:
----------
(1.) scdspeed/Throttle & Manifold/Intake Manifold/p0 = 0.543 bar
x:          0.49      dx:     -5.14e-15 (0)
(2.) scdspeed/Vehicle Dynamics/w = T//J w0 = 209 rad//s
x:           314      dx:      4.57e-13 (0)

Inputs:
----------
(1.) scdspeed/Throttle  perturbation
u:          2.94    [-Inf Inf]

Outputs:
----------
y:         3e+03    (3e+03)

Operating Point Search Report:
---------------------------------

Operating Report for the Model scdspeed.
(Time-Varying Components Evaluated at time t=0)

Operating point specifications were successfully met.
States:
----------
(1.) scdspeed/Throttle & Manifold/Intake Manifold/p0 = 0.543 bar
x:         0.473      dx:      1.13e-11 (0)
(2.) scdspeed/Vehicle Dynamics/w = T//J w0 = 209 rad//s
x:           419      dx:     -1.49e-10 (0)

Inputs:
----------
(1.) scdspeed/Throttle  perturbation
u:          5.83    [-Inf Inf]

Outputs:
----------
y:         4e+03    (4e+03)

```

モデルの線形化

```io(1) = linio('scdspeed/throttle (degrees)',1,'input');
```

モデルを線形化して、条件ごとにボード線図の振幅応答をプロットします。

```sys = linearize('scdspeed',op,io);
bodemag(sys)
```

モデルを閉じます。

```bdclose('scdspeed')
```