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Navigation: Output functions

Alternator control

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Alternator voltage control

 

Voltage control

Enables or disables the output voltage control duty.

 

Output type

Sets the output type, normal or inverted signal duty.

Normal, high duty = high power

inverted, low dUty = high power

 

Target voltage

The target alternator voltage (V).

 

PWM frequency

PWM frequency (Hz) to use on the output. <-- Make sure to use the correct frequency of your alternator by checking with the manufacturer.

 

P gain

P-value in the PI control regulation.

 

I gain

I-value in the PI control regulation.

 

Min control duty

Minimum duty to be applied to the output.

 

max control duty

Whether to use a fixed value or use a table to limit the max output duty, set to table and limit the max duty with the engine run-time axis to limit the alternator from stalling the engine directly on start-up.

 

 

Example

 

clip0942

The above is an example to control the Ford Coyote 5.0 alternator, working at 120Hz, but MAKE SURE TO ENTER YOUR ALTERNATORS CORRECT FREQUENCY. <-- To low frequency can cause sever damage on your engine and/or alternator.

 

 

 

PID control

PID is a "closed loop" control algorithm (instructions for solving a task) used to adjust a control value, (eg a idle valve position). In order to process actual values ​​(eg engine speed ) to match the desired TARGET value (eg, idle speed ) then adjusts the PID-algorithm control value according to these three elements.

 

 

Summary

P is used to bring the value close to the target.

I is used to bringing the error to zero.

D is used to dampen the response.

 

 

Setup process

P and I must always be used (not allowed to be zero), D is optional and not always necessary.

 

Usually starting by increasing the P and I together (using the same values) until it becomes slightly unstable.

Bring in some D to counteract that, and then fine-tune each value. Often by reducing P and increasing I.

The overall goal is to use as high values as possible while still having a stable response.

Then decrease all values a bit to add some safety margin to prevent overshoot or oscillation.

 

 

Typical problems (P)

Too low: Does not reach target, slow response.

Too high: Fast oscillation.

 

Typical problems (I)

Too low: Does not reach the target, slow response, overshoots and recovers slowly.

Too high: Oscillation.

 

Typical problems (D)

Too low: Overshoot.

To high:  Oscillation.

 

 

 

Example

clip1056

The above "%/100" means % per 100 error.

Example: 100 error --> 100% duty outputed.