PIDы Мазды по лоаду (PID 04 и PID 43).

Обсуждение адаптеров и подключения к автомобилю - использование, проблемы, решения
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TPLK
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Joined: Mon Apr 18, 2016 8:26 am
Vehicle: Mazda CX7'11

PIDы Мазды по лоаду (PID 04 и PID 43).

Post by TPLK »

Здравствуйте!

Подскажите, очень интересует вопрос, PIDы для Мазды по лоаду считаются примерно (или точно) по алгоритму, процитированному ниже :?:
Снимаю логи при самонастройке ЭБУ (настройка как раз по лоаду), но некоторое сомнение присутствует.

Или PID показывается напрямую из ЭБУ, без расчетов в программе?

Спасибо.
Calculated LOAD Value (PID 04)

The calculated load value LOAD_PCT is a percentage of peak available torque (current airflow / peak airflow @sea level) * (BARO @ sea level / BARO) * 100%

LOAD_PCT = [current airflow] / [(peak airflow at WOTstp as a function of rpm) * (BARO/29.92) * SQRT (298 / (AAT+273))]

--- STP = Standard Temperature and Pressure = 25 °C, 29.92 in Hg BARO,
--- SQRT = square root
--- WOT = wide open throttle
--- AAT = Ambient Air Temperature in °C

Characteristics of LOAD_PCT are:
— Reads 1.0 at WOT at any altitude, temp or rpm for both NA and boosted engines.
— Indicates percent of peak available torque.
— Linearly correlated with engine vacuum
— Often used to schedule power enrichment.
— Compression ignition engines shall support this PID using fuel flow in place of airflow.




Absolute Load Value (PID 43)


The absolute load value LOAD_ABS is the normalized value of air mass per intake stroke displayed as a percent.

LOAD_ABS = [air mass (g / intake stroke)] / [1.184 (g / intake stroke) * cylinder displacement in liters]

Where:
--- air mass (g / intake stroke) = [total engine air mass (g/sec)] / [rpm (revs/min)* (1 min
/ 60 sec) * (1/2 # of cylinders (strokes / rev)]

--- [1.184 (g / intake stroke) * cylinder displacement in liters] = [maximum air mass
(g)/intake stroke at WOTstp at 100% volumetric efficiency] * 100%.

--- (maximum air mass (g)/intake stroke at WOTstp at 100% volumetric efficiency) = a
constant for a given cylinder swept volume.

--- The constant is 1.184 (g/liter 3) * cylinder displacement (liter 3/intake stroke) based on
air density at STP.

--- STP = Standard Temperature and Pressure = 25 °C, 29.92 in Hg (101.3 kPa) BARO.
--- WOT = wide open throttle.


Characteristics of LOAD_ABS are:
— Ranges from 0 to approximately 0.95 for NA engines, 0 – 4 for boosted engines.
— Linearly correlated with engine indicated and brake torque.
— Often used to schedule spark and EGR rates.
— Peak value of LOAD_ABS correlates with volumetric efficiency at WOT.
— Indicates the pumping efficiency of the engine for diagnostic purposes.
Spark ignition engine are required to support PID $43. Compression ignition (diesel) engines are not required to support this PID.
FORScan
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Re: PIDы Мазды по лоаду (PID 04 и PID 43).

Post by FORScan »

Этот алгоритм реализован внутри PCM для расчета этих параметров. Диагностические сканеры просто считывают уже расчитанный параметр из PCM, преобразуют его в общепринятые единицы измерения и показывают. Данные параметры относятся к OBDII, формулы преобразования есть везде, например вот: https://ru.wikipedia.org/wiki/OBD-II_PIDs
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