russian wrote: ↑Sat Feb 16, 2019 9:57 pm
Do we have a thread suitable to rail pressure control logic discussion? I assume this thread is about the board. Am I missing something or are we supposed to start by figuring out what logic is needed to do what exacly with high pressure pump control?
What's the issue about the fuel pump?
Just download the PC-Link software and open the base map for gdi.
https://www.linkecu.com/software-support/
You will find both the settings/variables needed for E-Throttle and injectors.
If you open Help, you will also find descriptions for everything.
Link ECU are my favorite aftermarket off all times. I run it in my race-car.
GDI Fuel pump control from help file:
Fuel Pump Control provides the required functionality to drive various different types of fuel pump speed control configurations.
The following fuel pump and fuel pump speed control configurations are supported:
· Simple Fuel Pump On/Off relay.
· Dual Speed Control through relayed switched ballast resistor (most older Toyota).
· Triple Speed Control. As used on Nissan GTR.
· Three Stage PWM speed control (eg Toyota Supra, Subaru Impreza)
· Closed Loop Fuel Pressure Control. As used on some modern and GDI vehicles. Controls fuel pressure to match a desired target pressure.
· Open Loop Variable Fuel Pump Speed Control. Allows control of a fuel pump speed control module based on injector flow.
Prime Time
In all fuel pump speed control modes, the Prime Time setting is available and sets how long the fuel pump will run for when the key is first turned on. A typical value is 3 seconds. As soon as engine speed is detected the fuel pump will run continuously until the engine stops.
Speed Control Method
Sets the mode used to control an Auxiliary Output that is configured as FP Speed. See the following sections for more information on the supported modes.
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Simple Fuel Pump On/Off Control
This mode requires that an Auxiliary Output is wired to the fuel pump relay and configured as Fuel Pump. No other configuration is required. Speed Control Method can be set to OFF as it has no effect.
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Dual / Triple Speed Control
This type of control is used where two or three relays (or a control module) are used to switch the fuel pump between different speeds. The speeds are regulated by the use of current limiting resistors or special circuitry in the control module.
Two Auxiliary Outputs are required to use this mode:
1. One Auxiliary Output must be wired to the main fuel pump relay (the one that can turn the fuel pump off completely). This Auxiliary Output must be configured as Fuel Pump.
2. Another Auxiliary Output must be wired to the speed control relay (the one that switches in the resistor). This Auxiliary Output must be configured as FP Speed.
To use this mode Speed Control Method must be set to General X Over. This will allow the following settings to be adjusted:
· Eng Speed X Over - Sets the Engine Speed that fuel pump speed changes from low to high speed.
· Inj DC X Over - Sets the fuel flow that the fuel pump changes from low to high speed.
When Inj Duty Cycle is greater than Inj DC X Over OR Engine Speed is greater than Eng Speed X Over high speed pump mode is activated. Note that there is a 2% hysteresis on Inj Duty Cycle to prevent erratic switching.
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Three Stage PWM Speed Control
This type of control uses a Pulse Width Modulated (PWM) signal to a fuel pump speed control module to control the fuel pump speed in three steps. Only one Auxiliary Output is required to use this mode. That Auxiliary Output must be wired to the fuel pump speed control module and configured as FP Speed.
To use this mode set Speed Control Method to 80Hz 33/66/100% DC. The control will apply either 33% 66% or 100% duty cycle to the speed control module depeding on fuel flow. The following settings are available in this mode:
· FP Low -> Med - Sets the Inj Duty Cycle at which low to medium speed transition occurs.
· FP Med -> High - Sets the Inj Duty Cycle at which medium to high speed transition occurs.
Actual duty cycle applied to the fuel pump speed controller can be viewed with the FP Speed (%DC) parameter (found under Auxiliary Outputs).
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Closed Loop Pressure Control
This type of control continuously varies a PWM signal to the fuel pump speed control module to regulate measured fuel pressure to a target value. Only one Auxiliary Output is required to use this mode. That Auxiliary Output must be wired to the fuel pump speed control module and configured as FP Speed. An Analog Input must also be wired to a fuel pressure sensor and correctly configured to display calibrated Fuel Pressure.
Note that a special fuel pump speed control module is required for this type of control. A solid state relay will not be able to switch fast enough for variable speed fuel pump control.
Most OEM vehicles that require this type of control have the correct mechanical system to suit it. This type of control does not use a fuel pressure regulator. Only a small bleed is used to keep some fuel circulating in the system. Fuel tank heating is greatly reduced due to reduced fuel circulation and reduced fuel pump current.
To use this mode set Speed Control Method to Closed Loop. The following settings will be available:
· Fuel Pressure Target Table - Sets the target fuel pressure for given conditions (typically load and engine speed). Fuel Pressure Target is the interpolated value from this table.
· Startup Override Pressure - This pressure is used instead of the Fuel Pressure Target Table during engine starting. It allows removal of air from the system, and is required for correct operation of some GDI high pressure pumps.
· Feed Forward - Used to improve the response when Fuel Pressure overshoots or undershoots Fuel Pressure Target.
· Proportional Gain - The proportional gain component in the PID controller.
· Integral Gain - The integral gain component in the PID controller.
· Derivative Gain - The derivative gain component in the PID controller.
· Pump Off DC - The duty cycle that will be applied to the fuel pump speed control module when the engine is not running.
· Max DC Clamp - The maximum duty cycle that will be applied to the fuel pump speed control module while running.
· Min DC Clamp - The minimum duty cycle that will be applied to the fuel pump speed control module while running.
Actual duty cycle applied to the fuel pump speed controller can be viewed with the FP Speed (%DC) parameter (found under Auxiliary Outputs).
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Open Loop Pressure Control
This type of control uses a Pulse Width Modulated (PWM) signal to a fuel pump speed control module to regulate the fuel pump speed. Only one Auxiliary Output is required to use this mode. That Auxiliary Output must be wired to the fuel pump speed control module and configured as FP Speed. Note that a special fuel pump speed control module is required for this type of control. A solid state relay will not be able to switch fast enough for variable speed fuel pump control.
This type of control is normally used on a system with a fuel pressure regulator. The idea is to maintain a constant flow in the fuel return line for all injector flows. Keeping a constant flow through the regulator prevents fuel pressure creep. Reducing fuel pump speed when fuel demand is low also reduces fuel pump current, noise and fuel heating.
To use this mode set Speed Control Method to Open Loop. The following settings will be available:
· Prime Duty cycle - Sets the duty cycle used during Prime Time.
· FP Speed Table - Sets the desired fuel pump speed depending on Inj Duty Cycle. 0% will be pump stopped,100% will be full speed, 50% will be half speed etc. Note, the number in this table is not necessarily the duty cycle applied to the fuel pump speed controller, it is the desired fuel pump speed at a particular Inj Duty Cycle. The actual duty cycle applied to the fuel pump speed controller will depend on the following settings (refer to the equation shown below). The X Axis numbers (injector duty cycle) can be adjusted as required by pressing the X key while on this table.
· Multiplier - Scales the duty cycle to the fuel pump speed control module. For example if 80% FP Speed is desired and the pump controller needs 40% duty cycle to run the pump at 80% speed then set Multiplier to 0.5 %/%. If the fuel pump speed control module outputs the same duty cycle as its input then set this number to 1 %/%.
· Offset - Corrects the duty cycle sent to the fuel pump speed control module. This will normally be zero. For example, if the fuel pump speed control module requires a 40% duty cycle input to achieve 50% speed then Offset will be -10%.
· Min DC Clamp - The minimum duty cycle that will be applied to the fuel pump speed control module. Most pumps will not turn below approx 20% duty cycle. Set this to a value well above the pumps stalling duty cycle.
· Max DC Clamp - The maximum duty cycle that will be applied to the fuel pump speed control module. Note, some modules will go into an error state if a too high duty cycle (eg above 95%) is applied. This setting can also be used to limit max pump speed where an oversized fuel pump is used.
Actual duty cycle applied to the fuel pump speed controller can be viewed with the FP Speed (%DC) parameter (found under Auxiliary Outputs).
The duty cycle applied to the fuel pump speed controller is calculated as:
FP Speed (%DC) = FP Speed Table x Multiplier + Offset , clamped between Max DC Clamp and Min DC Clamp
also how did I forget a place for 12V and Gnd. Cool to see the first spin is being built.