File sstep_stall.c¶

FileList > src > sstep_stall.c

#include "sstep_internal.h"

Public Functions¶

Type	Name
bool	sstep_stall_check (struct sstep_ctx * m) Stall decision of one slow loop period, against the command of the period that just ended (vel_cmd, ff_cmd).
void	sstep_stall_observe (struct sstep_ctx * m, const struct sstep_sincos * sc, const sstep_acc_t v_applied) Back-EMF observer of one fast loop period (fast loop, current drive).
void	sstep_stall_reset (struct sstep_ctx * m) Reset the stall detector when the outputs are enabled: empty voltage history, filters at zero, current history from the last measurement.
void	sstep_stall_status (const struct sstep_ctx * m, struct sstep_status * status) Fill the observer fields of a status (zero when stall detection is off).

Public Static Functions¶

Type	Name
int64_t	abs_i64 (int64_t v) \|v\| for \|v\| < 2^63.
sstep_angle_t	atan2_turn (int32_t y, int32_t x) Angle of the vector (x, y), atan2(y, x), in 2^-32 turn (CORDIC, vectoring mode).
int32_t	emf_mv (const struct sstep_ctx * m, uint32_t axis) Filtered back-EMF of one axis (0 = d, 1 = q) [mV].
uint64_t	muldiv_u64 (uint64_t a, uint64_t b, uint64_t d) a b / d (truncated) without overflow for a < 2^42, b < 2^25, 0 < d < 2^35.*

Macros¶

Type	Name
define	CDEG_PER_TURN `36000` Centidegrees per turn.
define	CORDIC_NORM `((int32\_t)0x08000000)` The CORDIC operands are scaled up to at least 2^27 for resolution; the CORDIC gain (1.65 sqrt(2)) keeps them below 2^30.*
define	CORDIC_STEPS `16U` CORDIC iterations of atan2_turn() (last step atan(2^-15) = 0.0017 deg).
define	HALF_TURN `0x80000000U` Half a turn of sstep_angle_t .
define	OFF_ONE `((int64\_t)65536)` Fixed point one of sstep_ctx::emf_off (mV 2^16).*
define	TURN `((int64\_t)4294967296)` One turn of sstep_angle_t as a 64-bit value.
define	TWO_PI_DEN `113U`
define	TWO_PI_NUM `710U` 2 pi = 710 / 113, as in the gain derivation.

Public Functions Documentation¶

function sstep_stall_check¶

Stall decision of one slow loop period, against the command of the period that just ended (vel_cmd, ff_cmd).

bool sstep_stall_check (
    struct sstep_ctx * m
)

Parameters:

m Driver state.

Returns:

true when the stall condition has persisted for stall_time_ms.

function sstep_stall_observe¶

Back-EMF observer of one fast loop period (fast loop, current drive).

void sstep_stall_observe (
    struct sstep_ctx * m,
    const struct sstep_sincos * sc,
    const sstep_acc_t v_applied
)

Uses the voltage computed two periods ago (applied during the period that just ended), the measured currents and the commanded angle, then stores v_applied.

Parameters:

m Driver state; i_meas holds the currents of this period.
sc Sine and cosine of the commanded angle of this period.
v_applied Phase voltages computed in this period [pu V].

function sstep_stall_reset¶

Reset the stall detector when the outputs are enabled: empty voltage history, filters at zero, current history from the last measurement.

void sstep_stall_reset (
    struct sstep_ctx * m
)

Parameters:

m Driver state.

function sstep_stall_status¶

Fill the observer fields of a status (zero when stall detection is off).

void sstep_stall_status (
    const struct sstep_ctx * m,
    struct sstep_status * status
)

Parameters:

m Driver state.
status Status to complete.

Public Static Functions Documentation¶

function abs_i64¶

|v| for |v| < 2^63.

static int64_t abs_i64 (
    int64_t v
)

function atan2_turn¶

Angle of the vector (x, y), atan2(y, x), in 2^-32 turn (CORDIC, vectoring mode).

static sstep_angle_t atan2_turn (
    int32_t y,
    int32_t x
)

0 for the zero vector.

Parameters:

y Components, |x|, |y| < 2^27.

function emf_mv¶

Filtered back-EMF of one axis (0 = d, 1 = q) [mV].

static int32_t emf_mv (
    const struct sstep_ctx * m,
    uint32_t axis
)

function muldiv_u64¶

a * b / d (truncated) without overflow for a < 2^42, b < 2^25, 0 < d < 2^35.

static uint64_t muldiv_u64 (
    uint64_t a,
    uint64_t b,
    uint64_t d
)

Macro Definition Documentation¶

define CDEG_PER_TURN¶

Centidegrees per turn.

#define CDEG_PER_TURN `36000`

define CORDIC_NORM¶

The CORDIC operands are scaled up to at least 2^27 for resolution; the CORDIC gain (1.65 * sqrt(2)) keeps them below 2^30.

#define CORDIC_NORM `((int32_t)0x08000000)`

define CORDIC_STEPS¶

CORDIC iterations of atan2_turn() (last step atan(2^-15) = 0.0017 deg).

#define CORDIC_STEPS `16U`

define HALF_TURN¶

Half a turn of sstep_angle_t .

#define HALF_TURN `0x80000000U`

define OFF_ONE¶

Fixed point one of sstep_ctx::emf_off (mV * 2^16).

#define OFF_ONE `((int64_t)65536)`

define TURN¶

One turn of sstep_angle_t as a 64-bit value.

#define TURN `((int64_t)4294967296)`

define TWO_PI_DEN¶

#define TWO_PI_DEN `113U`

define TWO_PI_NUM¶

2 pi = 710 / 113, as in the gain derivation.

#define TWO_PI_NUM `710U`

The documentation for this class was generated from the following file src/sstep_stall.c