请教大家：ISO15031（J979)中对计算负荷、绝对负荷、当量指令比的定义

宁波老李

PID $04 Calculated LOAD Value  DEFINITION
The OBD regulations previously defined CLV as:
(current airflow / peak airflow @sea level) * (BARO @ sea level / BARO) * 100%
Various manufacturers have implemented this calculation in a variety of ways. The following definition, although a little more restrictive,
will standardise and improve the accuracy the calculation.
LOAD_PCT = [current airflow] / [(peak airflow at WOT@STP as a function of rpm) * (BARO/29.92) * SQRT(298/(AAT+273))]
— Where: STP = Standard Temperature and Pressure = 25 °C, 29.92 in Hg BARO, SQRT = square root,
— WOT = wide open throttle, AAT = Ambient Air Temperature and is in °C
Characteristics of LOAD_PCT are:
— Reaches 1.0 at WOT at any altitude, temperature or rpm for both naturally aspirated and boosted engines.
— Indicates percent of peak available torque.
— Linearly correlated with engine vacuum
— Often used to schedule power enrichment.
— Compression ignition engines (diesels) shall support this PID using fuel flow in place of airflow for the above calculations.
NOTE   Both spark ignition and compression ignition engines shall support PID $04. See PID $43 for an additional definition
of engine LOAD.
—PID $43 Absolute Load Value DEFINITION
The absolute load value has some different characteristics than the LOAD_PCT defined in PID 04 This definition, although restrictive,
will standardise the calculation. LOAD_ABS is the normalised 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 litres]
Derivation:
—  air mass (g / intake stroke) = [total engine air mass (g/sec)] / [rpm (revs/min)* (1 min / 60 sec) * (1/2 # of
cylinders (strokes / rev)],
—  LOAD_ABS = [air mass (g)/intake stroke] / [maximum air mass (g)/intake stroke at WOT@STP at 100% volumetric efficiency]
* 100%.
Where:
—  STP = Standard Temperature and Pressure = 25 °C, 29.92 in Hg (101.3 kPa) BARO, WOT = wide open throttle.
The quantity (maximum air mass (g)/intake stroke at WOT@STP at 100% volumetric efficiency) is a constant for a given cylinder swept
volume. The constant is 1.184 (g/litre 3) * cylinder displacement (litre 3/intake stroke) based on air density
at STP.
Characteristics of LOAD_ABS are:
—  Ranges from 0 to approximately 0.95 for naturally aspirated 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.
NOTE   See PID $04 for an additional definition of engine LOAD.

PID $44 Commanded Equivalence Ratio DEFINITION
Fuel systems that utilise conventional oxygen sensor shall display the commanded open loop equivalence ratio while the fuel control
system is in open loop. EQ_RAT shall indicate 1.0 while in closed loop fuel.
Fuel systems that utilise wide-range/linear oxygen sensors shall display the commanded equivalence ratio in both open loop and
closed loop operation.
To obtain the actual A/F ratio being commanded, multiply the stoichiometric A/F ratio by the equivalence ratio. For example, for
gasoline, stoichiometric is 14.64:1 ratio. If the fuel control system was commanding an 0.95 EQ_RAT, the commanded A/F ratio to the
engine would be 14.64 * 0.95 = 13.9 A/F
由于我不懂E文，看了不大清楚清楚，请教各位，给个明确的中文解释，谢谢！
重点是：
LOAD_PCT = [current airflow] / [(peak airflow at WOT@STP as a function of rpm) * (BARO/29.92) * SQRT(298/(AAT+273))]

LOAD_ABS = [air mass (g / intake stroke)] / [1.184 (g / intake stroke) * cylinder displacement in litres]
不明白的是：
     1、计算负荷中的即时空气流量（current airflow）如果是由空气质量流量计获取的话，绝对负荷值中的空气质量（air mass ）又是从哪里获取的？
     2、绝对负荷中的空气质量（air mass ）如果也是由空气质量流量计获取的话，这个在某些情况下是不准确的，因为空气质量流量计有失真而且有碳罐、EGR流量的影响。我认为比较可靠的来源应该是喷油量，因为在闭环时的喷油量所对应的空气质量最接近实际进入气缸的空气质量。
     3、计算负荷中的节气门全开时的峰值流量（peak airflow） 是从哪里来的，是不是来源于同转速时节气门全开的充气模型
     4、PID $44 Commanded Equivalence Ratio是不是目标空燃比、或者叫指令空燃比？

ziqiancn

解答一下呗