Fuel injector driver for cold start of high resistance injector
View Patent ↗An engine control system includes a fuel injector and a sensor that is configured to provide a signal indicative of a temperature. A controller is in communication with the sensor. The controller includes a fuel injector driver in communication with the fuel injector. The fuel injector driver includes a saturated mode and a peak and hold mode. The controller is configured to command the fuel injector driver to control the fuel injector with one of the saturated mode or the peak and hold mode based upon the signal. For a high resistance injector, the peak and hold mode is used in cold weather conditions to break free an injector seal, and then the fuel injector driver reverts to the saturated mode.
1. An engine control system comprising:
a fuel injector;
a sensor configured to provide a signal indicative of a temperature;
a controller in communication with the sensor, the controller includes a fuel injector driver in communication with the fuel injector, the fuel injector driver includes a saturated mode and a peak and hold mode, the controller configured to command the fuel injector driver to control the fuel injector with one of the saturated mode or the peak and hold mode based upon the signal;
a crank angle sensor in communication with the controller and configured to detect a number crank pulses;
wherein the controller is configured to command the fuel injector driver to operate the fuel injector in the peak and hold mode if the engine temperature is below a threshold temperature; and
wherein the controller is configured to command the fuel injector driver to operate the fuel injector in the peak and hold mode if the number of crank pulses during a cold start is below a predetermined number.
2. The engine control system according to claim 1 , wherein the fuel injector includes an actuation coil surrounding a valve assembly, an elastomeric seal is secured to the valve assembly and abuts a seat in a closed position, the actuation coil configured to move the valve assembly and elastomeric seal from the closed position to an open position in response to fuel injector driver.
3. The engine control system according to claim 2 , wherein the actuation coil has a resistance of greater than 7 ohms.
4. The engine control system according to claim 3 , wherein the actuation coil has a resistance in a range of 12-16 ohms.
5. The engine control system according to claim 1 , wherein the sensor is a temperature sensor.
6. The engine control system according to claim 5 , comprising a cooling system, wherein the temperature sensor is provided in the cooling system, and the temperature is a coolant temperature within the cooling system.
7. The engine control system according to claim 1 , wherein the threshold temperature is 0° C.
8. The engine control system according to claim 1 , wherein the controller is configured to command the fuel injector driver to revert to operate the fuel injector in the saturated mode after a predetermined number of the cycle with the peak and hold mode.
9. The engine control system according to claim 8 , wherein fuel injector is configured to move from a closed position to an open position, and the predetermined peak time corresponds to approximately twice the time it takes for the fuel injector to move from the closed position to the open position in response to the peak and hold mode.
10. The engine control system according to claim 1 , comprising a combustion chamber and a first fuel injector, wherein the fuel injector is a second fuel injector, the first and second fuel injectors respectively include resistances in a range of 0-7 ohms and 8-20 ohms, the fuel injector driver in communication with the first and second fuel injectors and configured to selectively operate one of the first and second fuel injectors based upon one of at least two fuel sources.
11. A method of controlling a fuel injector comprising the steps of:
operating a fuel injector in one of a saturated mode or a peak and hold mode based upon a temperature and a number of crank pulses detected by a crank angle sensor.
12. The method according to claim 11 , wherein the operating step includes operating the fuel injector in a peak and hold mode during a cold start condition in which the temperature is below a threshold temperature.
13. The method according to claim 12 , wherein the operating step includes reverting to operating the fuel injector in the saturated mode after a predetermined hold time during the peak and hold mode.
14. The method according to claim 12 , wherein the peak and hold mode fuel injector operating step includes breaking an injector seal away from a seat.
15. The method according to claim 12 , wherein the fuel injector has an actuator coil with a resistance in a range of 7-16 ohms.
16. The method according to claim 11 , wherein the peak and hold mode fuel injector operating step and the saturated mode fuel injector operating step are performed using the same fuel injector driver.
17. The method according to claim 16 , comprising the step of operating a low resistance fuel injector with the fuel injector driver in the peak and hold mode when using a first fuel, and comprising the step of operating a high resistance fuel injector driver with the same fuel injector driver in one of a saturated mode or a peak and hold mode based upon a temperature when using a second fuel.