#include <hellen_board_id.h>

Inheritance diagram for HellenBoardIdSolver:

Collaboration diagram for HellenBoardIdSolver:

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Public Member Functions
float	fx (float x) override

float	dfx (float x) override

float	solve (float Tc1, float Tc2, float x0, float y, float deltaX)

Private Attributes
float	k1

float	k2

float	k3

Detailed Description

Definition at line 30 of file hellen_board_id.h.

Member Function Documentation

◆ dfx()

float HellenBoardIdSolver::dfx ( float x )

inlineoverride

Definition at line 38 of file hellen_board_id.h.

                                {
        return (-1.0f / (x * x)) * (k1 * exp(k1 / x) - k2 * exp(k2 / x) + k3 * exp(k3 / x));
    }

◆ fx()

float HellenBoardIdSolver::fx ( float x )

inlineoverride

Definition at line 33 of file hellen_board_id.h.

                               {
        return exp(k1 / x) - exp(k2 / x) + exp(k3 / x) - 1.0;
    }

◆ solve()

float HellenBoardIdSolver::solve	(	float	Tc1,
		float	Tc2,
		float	x0,
		float	y,
		float	deltaX
	)

Definition at line 83 of file hellen_board_id.cpp.

                                                                                      {
    // the discharge time equals to the charge time
    float Td = Tc1;
 
    float iC = -1.0f / y;
    k1 = iC * Td;
    k2 = iC * (Tc1 + Td);
    k3 = iC * (Tc1 - Tc2);
 
    // the same method works for R (if C is known) or C (if R is known)
    auto result = NewtonsMethodSolver::solve(x0, deltaX, 20);
 
    // since we had https://github.com/rusefi/rusefi/issues/4084 let's add paranoia check
    // All real cases seem to converge in <= 5 iterations, so we don't need to try more than 20.
    if (!result) {
        criticalError("hellen boardID is broken");
        return 0;
    }
 
    return result.Value;
}