RAPID ZERO FLOW LUBRICATION METHODS FOR A HIGH PRESSURE PUMP

摘要

Methods are provided for rapid zero flow lubrication of a high pressure fuel pump, wherein a fuel rail pressure rapidly responds to commanded duty cycles. A method is needed to control operation of the high pressure pump during times when no direct injection is requested by an engine system and when operation of the high pressure pump is continued to maintain pump lubrication. To lubricate the high pressure pump while gaining zero flow rate data, methods are proposed that involve both open and closed loop control of the high pressure pump.

主权项

1. A method, comprising:
while not direct injecting fuel into an engine and while the engine is in a stabilized idling condition;
estimating a target fuel rail pressure based on a commanded target duty cycle of a high pressure fuel pump;performing a closed loop control scheme until fuel rail pressure reaches a percentage of the target pressure; andperforming an open loop control scheme until fuel rail pressure reaches the target fuel rail pressure.