Fuel pump with electronic controlled pressure regulation and failure mitigation

A fuel pump system for a vehicle, comprising:

• a primary fuel pump;
• a fuel tank;
• an auxiliary fuel pump in-line with the primary fuel pump and fluidly connected to the fuel tank;
• an electronic control circuit, the electronic control circuit including a processing device;
• a pressure sensor configured to measure an output pressure from the auxiliary fuel pump and to transmit a signal corresponding to the output pressure to the electronic control circuit;
• an electric motor configured to drive the auxiliary fuel pump at an operational motor speed, wherein the electric motor is electrically connected to the electronic control circuit;
• and
• wherein the electronic control circuit is configured to continuously adjust the operational motor speed via the processing device, based on the signal from the pressure sensor to maintain a predetermined constant output pressure, and
• wherein the electronic control circuit is further configured to sense a failure or disconnect in the pressure sensor or the processing device and to automatically switch control of the operational motor speed from the processing device to a fixed source that is configured to provide a fixed, predetermined operating voltage or power corresponding to a predetermined, safe speed in response to sensing the failure or disconnect, and
• wherein the electronic control circuit includes a Digital to Analog Converter in communication with the processing device under normal operating conditions, and an operational motor speed controller electrically connected to the Digital to Analog Converter and to the electric motor, the operational motor speed controller controlling the operational motor speed of the electric motor, wherein the processing device is configured to communicate a digital signal to the Digital to Analog Converter to maintain the predetermined constant output pressure based on the signal from the pressure sensor under normal operating conditions, the Digital to Analog Converter is configured to generate an analog voltage from the digital signal, and the operational motor speed controller is configured to control the operational motor speed of the electric motor based on the analog voltage generated by the Digital to Analog Converter from the digital signal, and
• wherein the electronic control circuit further includes a switch electrically connected to the operational motor speed controller and switchably connected to the Digital to Analog Converter and the fixed source, wherein the switch is configured to automatically switch a source of operating voltage to the operational motor speed controller from the Digital to Analog Converter to the fixed source for operation of the electric motor at the predetermined safe speed in response to sensing the failure or disconnect.

A fuel pump system for a vehicle, comprising:

• a primary fuel pump;
• a fuel tank;
• an auxiliary fuel pump in-line with the primary fuel pump and fluidly connected to the fuel tank;
• an electronic control circuit;
• a pressure sensor configured to measure an output pressure from the auxiliary fuel pump and to transmit a signal corresponding to the output pressure to the electronic control circuit;
• an electric motor configured to drive the auxiliary fuel pump at an operational motor speed, wherein the electric motor is electrically connected to the electronic control circuit;
• and
• wherein the electronic control circuit is configured to continuously adjust the operational motor speed based on the signal from the pressure sensor to maintain a predetermined constant output pressure;
• and
• a control panel switch having a plurality of modes of operation manually selectable by an operator of the vehicle, wherein one of the modes of operation selectable via the control panel switch is a high boost mode, wherein the high boost mode is set to a fixed voltage corresponding to a predetermined safe speed, and wherein the control panel switch in the high boost mode is electrically connected to the electric motor and bypasses the electronic control circuit.

A method of operating a fuel pump system for a vehicle, the fuel pump system including a primary fuel pump and an auxiliary fuel pump in-line with the primary fuel pump and fluidly connected to a fuel tank, and an electric motor for driving the auxiliary fuel pump, the method comprising:

• providing an electronic control circuit electrically connected to the electric motor, and a pressure sensor at an output of the auxiliary fuel pump;
• receiving, at the electronic control circuit, a signal from the pressure sensor corresponding to the output pressure measured by the pressure sensor at the output of the auxiliary fuel pump;
• communicating, via a processing device associated with the electronic control circuit, an operational motor speed to the auxiliary fuel pump based on the signal received from the pressure sensor;
• continuously adjusting, via the processing device, the operational motor speed based on the signal received from the pressure sensor under normal operating conditions to maintain a predetermined constant output pressure;
• and
• sensing, by the electronic control circuit, a failure or disconnect in the pressure sensor or the processing device, and automatically switching control, via the electronic control circuit, of the operational motor speed from the processing device to a fixed source that is configured to provide a fixed, predetermined operating voltage or power corresponding to a predetermined safe speed in response to sensing the failure or disconnect,
• wherein the fixed source is a potentiometer pre-set to a fixed voltage corresponding to the predetermined safe speed.

A method of operating a fuel pump system for a vehicle, the fuel pump system including a primary fuel pump and an auxiliary fuel pump in-line with the primary fuel pump and fluidly connected to a fuel tank, and an electric motor for driving the auxiliary fuel pump, the method comprising:

• providing an electronic control circuit electrically connected to the electric motor, and a pressure sensor at an output of the auxiliary fuel pump;
• receiving, at the electronic control circuit, a signal from the pressure sensor corresponding to the output pressure measured by the pressure sensor at the output of the auxiliary fuel pump;
• communicating, via a processing device associated with the electronic control circuit, an operational motor speed to the auxiliary fuel pump based on the signal received from the pressure sensor;
• continuously adjusting, via the processing device, the operational motor speed based on the signal received from the pressure sensor under normal operating conditions to maintain a predetermined constant output pressure;
• and
• sensing, by the electronic control circuit, a failure or disconnect in the pressure sensor or the processing device, and automatically switching control, via the electronic control circuit, of the operational motor speed from the processing device to a fixed source that is configured to provide a fixed, predetermined operating voltage or power corresponding to a predetermined safe speed in response to sensing the failure or disconnect,
• wherein the communicating, via the electronic control circuit, includes communicating a digital signal to a Digital to Analog Converter in the electronic control circuit to maintain the predetermined constant output pressure based on the signal received, at the receiving step, from the pressure sensor;
• and the continuously adjusting, by the electronic control circuit, under normal operating conditions includes generating, by the Digital to Analog Converter in the electronic control circuit, an analog voltage from the digital signal, and controlling, by an operational motor speed controller in the electronic control circuit, the operational motor speed of the electric motor based on the analog voltage generated by the Digital to Analog Converter,
• the method further including providing the electronic control circuit with a switch electrically connected to the operational motor speed controller and switchably connected to the Digital to Analog Converter and the fixed source, and pre-setting the fixed source to the fixed, predetermined operating voltage or power corresponding to the predetermined safe speed, and wherein the automatically switching, via the electronic control circuit, includes automatically switching, via the switch, a source of operating voltage from the Digital to Analog Converter to the fixed source to operate the electric motor at the predetermined safe speed in response to the sensing the failure or disconnect.

A method of operating a fuel pump system for a vehicle, the fuel pump system including a primary fuel pump and an auxiliary fuel pump in-line with the primary fuel pump and fluidly connected to a fuel tank, and an electric motor for driving the auxiliary fuel pump, the method comprising:

• providing an electronic control circuit electrically connected to the electric motor, and a pressure sensor at an output of the auxiliary fuel pump;
• receiving, at the electronic control circuit, a signal from the pressure sensor corresponding to the output pressure measured by the pressure sensor at the output of the auxiliary fuel pump;
• communicating, via a processing device associated with the electronic control circuit, an operational motor speed to the auxiliary fuel pump based on the signal received from the pressure sensor;
• continuously adjusting, via the processing device, the operational motor speed based on the signal received from the pressure sensor to maintain a predetermined constant output pressure;
• and
• providing, via a control panel switch, manually selectable modes of operation including a high boost mode set to a fixed voltage corresponding to the predetermined safe speed, the method further including operating the electric motor at the predetermined safe speed in response to selecting the high boost mode, wherein selecting the high boost mode bypasses the electronic control circuit.