Fuel Injection Valve Timing Detection via Coil Current Spectrum

The patent introduces an inflection point detection mechanism as an intermediary to indirectly determine valve-opening timing. Instead of directly measuring the valve position during boosted voltage operation, the system detects inflection points in the coil current waveform, which serve as reliable proxies for valve-opening events. This intermediary approach allows accurate timing detection without being disrupted by the high current conditions caused by boosted voltage.

The patent replaces direct mechanical or position-based detection methods with electrical waveform analysis. By substituting physical valve position measurement with analysis of electrical current characteristics (inflection points in the coil current waveform), the system achieves accurate timing detection that is immune to the electrical noise and high current conditions present during boosted voltage operation.

The patent employs periodic switching control where the switching element operates in on/off cycles to maintain constant current flow through the coil. This periodic action allows the system to achieve rapid valve opening through controlled current pulses while minimizing continuous high current flow, thereby reducing overall switching losses while maintaining fast response performance.

The patent dynamically adjusts current parameters (magnitude, duration, waveform shape) based on operating conditions to optimize the balance between valve opening speed and energy loss. By changing current parameters adaptively rather than maintaining fixed high current levels, the system achieves fast valve response only when necessary while reducing switching losses during normal operation.

The patent implements feedback control by continuously monitoring the coil current waveform, detecting inflection points that indicate actual valve-opening events, and using this detected timing information to precisely control injection timing. This feedback mechanism allows the system to adapt to actual valve behavior in real-time, achieving high timing precision without requiring complex mechanical timing mechanisms or additional sensors in the valve assembly.

The system uses the existing coil current waveform—already present for valve actuation—to simultaneously provide timing detection information. By extracting timing data from the self-generated electrical signals during normal operation, the system achieves precise timing measurement without adding separate detection sensors or complex external timing mechanisms to the injector assembly.