Lambdatronic LT4. Function Sheet

Transcription

1 Lambdatronic LT4 Function Sheet /31/2014

2 Table of Contents Table of Contents 1 Icons Description Pin Layout Life-Plug (AS PN) Function Diagrams of Lambda Value Detection Lambda Main Lambda Calc Lambda Heat Lambda Diagnosis PWM Calc Battery Voltage Detection Lables Description Typical Values Can Messages Sent Messages Receive Messages / 18 Lambdatronic LT4 Function Sheet Bosch Engineering

3 Icons Description 1 1 Icons Description Bosch Engineering Lambdatronic LT4 Function Sheet 3 / 18

4 2 Pin Layout Life-Plug (AS PN) 2 Pin Layout Life-Plug (AS PN) Pin Function V (Battery +) V (Battery +) 3 Ground (Battery -) 4 Ground (Battery -) 5 K-Line Diagnostic Connection 6 CAN1 + (high) 7 CAN1 (low) 8 Analog out 1 9 Analog out 2 10 Analog out 3 11 Analog out 4 12 Reference GND for anal. out 13 Shield 14 Pump Current LSU1 IP1 15 Virtual GND LSU1 VM1 16 Heater PWM LSU1 Uh-1 17 Heater (Batt +) LSU1 Uh+1 18 Setup Current LSU1 IA1 19 Nernst Voltage LSU1 UN1 20 Pump Current LSU2 IP2 21 Virtual GND LSU2 VM2 22 Heater PWM LSU2 Uh-2 23 Heater (Batt +) LSU2 Uh+2 24 Setup Current LSU2 IA2 25 Nernst Voltage LSU2 UN2 26 Pump Current LSU3 IP3 27 Virtual GND LSU3 VM3 28 Heater PWM LSU3 Uh-3 29 Heater (Batt +) LSU3 Uh+3 30 Setup Current LSU3 IA3 31 Nernst Voltage LSU3 UN3 32 Pump Current LSU4 IP4 33 Virtual GND LSU4 VM4 34 Heater PWM LSU4 Uh-4 35 Heater (Batt +) LSU4 Uh+4 36 Setup Current LSU4 IA4 37 Nernst Voltage LSU4 UN4 4 / 18 Lambdatronic LT4 Function Sheet Bosch Engineering

5 Function Diagrams of Lambda Value Detection Function Diagrams of Lambda Value Detection Lambda Main 3.2 Lambda Calc Bosch Engineering Lambdatronic LT4 Function Sheet 5 / 18

6 3 Function Diagrams of Lambda Value Detection 3.3 Lambda Heat 3.4 Lambda Diagnosis 3.5 PWM Calc 6 / 18 Lambdatronic LT4 Function Sheet Bosch Engineering

7 Function Diagrams of Lambda Value Detection Battery Voltage Detection 3.7 Lables afr B_can1OK B_can2OK batt_e batt_u batt_corr_u can_batt_u can_tmot canlam_offset_dis canlamh_on CJ125diag lam lam_e lam_o lam_of lam_u lam_uc lam_uf lamh_e lamh_mode lamh_u lamhpwm lamhu_p lamhu_t lamlimits_e lamoffset_b lamok lamout_u lampwm lamr Air fuel ratio State of CAN1 chip State of CAN2 chip Error battery voltlage detection battery voltage Correction battery voltage battery voltage via CAN engine temperature via CAN Inhibition flag for offset calibration (CAN Input) Lambda heaters switched on via CAN Lambda-chip CJ125 internal error code Lambda value Lambda value error Lambda value calibration offset Lambda value calibration offset filtered Lambda sensor voltage Lambda sensor calibrated voltage Lambda sensor filtered voltage Lambda heater error heater mode lambda probe heater voltage lambda probe Lambda heater PWM heater voltage lambda probe provisory Heater voltage lambda probe from characteristic line Lambda value beyond limits Lambda calibration active Lambda sensor operational Lambda output voltage Lambda PWM output value Lambda sensor internal impedance Bosch Engineering Lambdatronic LT4 Function Sheet 7 / 18

8 3 Function Diagrams of Lambda Value Detection lamr_f lamr_u lamt lamt_humax_b lamtok tdlamh BATT_U_CAN_CW BATT_U_DEF BATT_U_MAX BATT_U_MIN CANENABLE_CW CANID CANRATE CANSPEED_CW LAM_FIL LAM_LIN LAM_MAX LAM_MIN LAM_OPMODE_CW LAM_REF LAM_UAFR_FAK LAMH_ON_CW LAMHDEW_xx LAMHGRD_xx LAMHOFF_xx LAMHUxx LAMHUMAX_xx LAMHUMAXLOW_xx LAMLIMITS_DEL LAMOFFSET_DEL LAMOUTPWM LAMOUTU LAMR_FIL LAMR_GRD LAMR_OFF LAMREF_DEL LAMREF_FIL LAMREF_MAX LAMREF_MIN Lambda sensor internal impedance filtered Lambda sensor internal impedance voltage Lambda sensor temperature Conditition enabling maximum heating power lambda probe Lambda sensor operation temperature reached Timer dewpoint phase lambda probe Battery voltage detection selection switch power supply voltage of LT4 Upper battery voltage threshold for plausibility check Lower battery voltage threshold for plausibility check CAN enable Lambda CAN messages IDs (reconfigurable) CAN send frequency CAN baud rate (0->500kBaud 1->1000kBaud) Lambda filter time-constant Lambda value linearization curve Lambda value maximum limit Lambda value minimum limit Operating mode of Lamdatronic module channel x Lambda calibration reference voltage Factor air fuel ration Activating lambda heater by codeword Lambda heater voltage for dewpoint phase Lambda heater gradient Lambda heater offset voltage Lambda heater voltage predefined value Lambda heater voltage maximum value Maximum heater voltage lower temperature range Lambda value delay for limits passing Lambda calibration duration linearization curve from pwm -> voltage conversion desired voltage output lambda -> voltage Lambda internal impedance filter time-constant Lambda internal impedance gradient Lambda internal impedance offset Lambda calibration delay Lambda calibration offset filter time-constant Lambda value upper calibration limit Lambda value lower calibration limit 8 / 18 Lambdatronic LT4 Function Sheet Bosch Engineering

9 Function Diagrams of Lambda Value Detection 3 LAMT_MIN LAMTxx_LIN LAMT_HUMAX- LOW_xx LAMT_HUMAX_xx LAMTDIAG_MIN LAMTMOT_DEW LAMTYPE_CW TDLAMH_DEW Lambda sensor minimum operation temperature Lambda sensor temperature linearization curve Lower temperature threshold disabling high heating power Upper temperature threshold for enabling high heating power Lambda sensor minimum temperature for diagnosis engine temperature threshold for dewpoint detection Lambda type (0->LSU4.2 1->LSU4.9 2-> Mini-LSU) heating time for dewpoint phase 3.8 Description Description The wide range sensor LSU4.9/4.2 is used together with the evaluation-ic "CJ125" for a continuous Lambda control in the range between Lambda 0.65 and 4.0. The sensor contains a Nernst cell and a pump cell. The Lambda in the Nernst cell is controlled to Lambda = independent of the oxygen contents on the emission side, through a current through the pump cell. The closed loop control and evaluation of the current as well as a diagnosis function are performed in the CJ125. The current-proportional output voltage of the CJ125 "lam_u" is a measure for Lambda value (air/fuel ratio) and it is updated every 10 ms. The linearization LAM_LIN is a characteristic line with 22 table entries. The result of the interpolation is the current Lambda "lam". With a cold high-resistance sensor "lam=1" is indicated after the adjustment procedure. If the sensor becomes active due to the heating the operating readiness is set "lamok". For this to happen, the sensor heating must be working. The reference pump current is fixed at 20uA. The error "lam_e" is set whenever the CJ125 own diagnosis mechanisms detect short-circuits and under-voltage conditions, and when an inplausible sensor voltage level is present in "lam_u". A good-working LSU/CJ125 combination outputs a voltage between 0.2V and 4.0V. It could happen that extreme voltage levels appear on extreme mixture conditions (extreme enrichment/enleanment). Therefore a calibrateable delay can be used ("LAMLIMITS_DEL") for diagnosis detection. The lambda sensor heaters are controlled through the variables LAMH_ON_CW and canlamh_on. LAMH_ON_CW is a codeword which enables CAN control of the sensor heaters. canlamh_on is the CAN-supplied command to switch the sensor heaters on and off. If LAMH_ON_CW is switched off (set to 0), then the heaters will be switched off and cannot be switched on via CAN until LAMH_ON_CW is set to 1. If no CAN messages are used to switch the lambda sensor heaters on, then the default value for canlamh_on is 1 and the heaters status will be dependent only on LAMH_ON_CW. The heaters of the sensors (Ri20 C ~ 3 Ohm) are switched by transistors, which are triggered in a clocked fashion by processor ports in the 10ms grid (this heating is NOT valid for the LT4F1!). A permanent turn-on of the heater for a long time is not permitted. The heater is clocked with a fixed frequency of 200Hz, dur- Bosch Engineering Lambdatronic LT4 Function Sheet 9 / 18

10 3 Function Diagrams of Lambda Value Detection ing which the turn-on duration of heater is steadily increased starting with a cold sensor by a temperature dependent value LAMHOFF_xx and gradient LAMHGRD_xx and thereafter decreased again. The dew point heating feature initially supplies a small heating voltage to the lambda sensor to safely evaporate any moisture around the sensing element before heating at full power. The amount of time for the dew point heating phase can be set with the variable TDLAMH_DEW. Dew point heating is only activated if the engine temperature can_tmot supplied over CAN is below the setpoint variable LAMTMOT_DEW. If no engine temperature information is supplied over CAN, then the dew point heating phase is enabled by default. The sensor temperature is calculated out of the filtered internal resistance "lamr" and "LAMTxx_LIN". As soon as this temperature goes above "LAMT_MIN", "lamtok" will indicate that the sensor is sufficiently heated. For the best possible sensor operation, its ceramics must have a temperature of 780 C (LSU4.9), 750 C (LSU4.2), and 780 C (Mini-LSU4.9) respectively, so that the heater reacts accordingly. At this temperature the internal resistance has a value of 300 Ohm (LSU4.9 and Mini-LSU4.9) or 82.5 Ohm (LSU4.2) respectively. The heater error "lamh_e" is set when the CJ125 own diagnosis mechanisms detect errors at the output stage (short-circuits or open load). The internal diagnostic function of the CC125 is activated only when lamt goes over LAMTDIAG_MIN, whereas short-circuit detection is activated. Below this threshold a correct diagnostic is not possible. The lambda signal output is realized via a CAN message or analog signal output. Please find further information regarding the CAN specification in CAN messages. Using LAMOUTU the measured lambda value related output voltage can be defined (0 5 V). To compensate hardware tolerances the linearization curve LA- MOUTPWM can be used. It is possible to use either lean or rich optimized measuring mode of LT4 according to the measuring requirements and can be configured by codeword LAM_OPMODE_CW. The LT4 has a new voltage compensation function. The electronics detects the voltage supply from either Batt_U or CAN_Batt_U. The selection can be made in the parameter BATT_U_CW using ModasSport. During the operation, the LT4 ensures that the heating voltage remains within the range given by BATT_U_MIN and BATT_U_MAX. If the voltage supply falls below the BATT_U_MIN or raises above the BATT_U_MAX, the value defined in the variable BATT_U_DEF will be taken as default voltage. This active voltage compensation was implemented in order to prevent any damages in the ceramic element of the lambda probe caused by an undesired thermal shock. 3.9 Typical Values BATT_U_CAN_CW = 0 internal battery voltage detection BATT_U_MAX = 18 V BATT_U_MIN = 3 V 10 / 18 Lambdatronic LT4 Function Sheet Bosch Engineering

11 Function Diagrams of Lambda Value Detection 3 BATT_U_DEF = 14 V // value of can_batt_u is used to define power supply CANENABLE_CW = 1 // CAN interface enabled CANRATE = 10 ms CANSPEED_CW = 1000 kbaud LAM_FIL = 20 ms LAM_MAX = 4.5 V LAM_MIN = 0.2 V LAM_OP_MODE = lean mode LAM_UAFR_FAK = 14.7 LAM_REF = 1.5 V LAMH_ON_CW = CAN controlled heater is enabled without CAN communication! LAMHU_DLIMHI = +10 V/sec LAMHU_DLIMLO = -10 V/sec LAMLIMITS_DEL = 1 s LAMOFFSET_DEL = 0.15 s LAMOFFSET_PER = 300 s LAMR_FIL = 320ms LAMR_GRD = 408 Ohm/V LAMR_OFF = 0.3 V LAMREF_DEL = 0.05 s LAMREF_FIL = s LAMREF_MAX = 1.02 LAMREF_MIN = 0.98 LAMT_MIN = 650 C LAMTDIAG_DEL = 10 s LAMTMOT_DEW = 50 C LAMTYPE_CW = LSU 4.9 TDLAMH_DEW = 30 s lam_uc LAM_LIN Bosch Engineering Lambdatronic LT4 Function Sheet 11 / 18

12 3 Function Diagrams of Lambda Value Detection lam LAMOUTU Further application data have to be taken from datasheets of supported LSU types. 12 / 18 Lambdatronic LT4 Function Sheet Bosch Engineering

13 Can Messages Can Messages Sent Messages Using the CANID parameter line, the CAN messages can be reconfigured. Note that these IDs must be in decimal form and not the usual hexadecimal one! To change an ID, simply select the index number starting with 1 for ID1, 2 for ID2 and so on, and change the corresponding parameter-line value. Default IDs ID ID1 (send) ID2 (send) ID3 (send) ID4 (send) ID5 (receive) CANID 0x770 (1904) unused 0x772 (1906) 0x773 (1907) 0x774 (1908) MESSAGE ID 1 Byte Value 0 lam1 (low) 1 lam1 (high) 2 lam2 (low) 3 lam2 (high) 4 lam3 (low) 5 lam3 (high) 6 lam4 (low) 7 lam4 (high) MESSAGE ID 3 Byte Value 0 lam1t 1 lam2t 2 lam3t 3 lam4t MESSAGE ID 4 Byte Value 0 lamx_e 1 lamxheat_e 2 lamxok 3 canlamheat_on 4 lamxoffset_b 5 - Bosch Engineering Lambdatronic LT4 Function Sheet 13 / 18

14 4 Can Messages Notes 1 Bit * 5* 6* 7* lamx_e lam1_e lam2_e lam3_e lam4_e lam1he at1_e lam2he at_e lam3he at_e lam4he at_e lamxok lam1ok lam2ok lam3ok lam4ok lamxheat_e lamxoffset_b Lam1off set_b Lam2off set_b Lam3off set_b Lam4off set_b Notes 2 All values are unsigned (positive) values All word-wide values are in Intel (little-endian) byte-order All lambda-values are quantized with /bit and zero offset (range = 0 16) All temperatures are quantized with 5 C/bit and offset -40 C (range = C) The CAN refresh rate is 100Hz (10 ms) 4.2 Receive Messages This message can be used to switch off the lambda heaters by CAN command. MESSAGE ID 5 Byte Value 0 canlamheat_on 1 canlam_offset_dis 2 batt_u 3 tmot Notes 1 Byte canlam_offset_dis 0 canlam_offset_dis channel 1 1 canlam_offset_dis channel 2 2 canlam_offset_dis channel 3 14 / 18 Lambdatronic LT4 Function Sheet Bosch Engineering

15 Can Messages 4 3 canlam_offset_dis channel 4 4* canlam_offset_dis channel 5 5* canlam_offset_dis channel 6 6* canlam_offset_dis channel 7 7* canlam_offset_dis channel 8 Note: if canlamheat_on and LAMHEAT_ON_CW eqal 1: heaters are switched on After 2 seconds time out of message ID5 the heaters are switched on again. Configuration of CAN CANSPEED_CW: selects the baud rate of the CAN CANSPEED_CW = 0: 500 kbaud CANSPEED_CW = 1: 1000 kbaud Bosch Engineering Lambdatronic LT4 Function Sheet 15 / 18

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18 Bosch Engineering GmbH Motorsport Robert-Bosch-Allee Abstatt Germany