Brushless Motors for In-Tank Fuel Pumps

Most automotive fuel systems use a Fuel Delivery Module (FDM) with components to filter and pump gasoline at a specified pressure and flow rate from the fuel tank to the engine. The FDM uses a reservoir assembly to maintain a fuel supply at the pump inlet and support components such as pressure regulators and/or limiters, filters, level sensor, and the electrical and hydraulic connections that pass through the tank. Current systems predominantly use passive electrical components such as brush pumps and resistive fuel level sensors that are independently connected to a voltage supply and body control module, respectively. The high flow levels of these systems require high-power pumps that may operate continuously at maximum speed conditions. Some newer systems may employ a voltage controller to modulate the pump supply voltage to discrete speeds depending on projected engine demand, and provide some improvement in power consumption.