Stmicroelectronics S.r.l.

Maurizio Di Meglio

Francesco Pirozzi

Nicola Cesario

Giovanni Moselli

Paolo Amato

Ferdinando Taglialatela-Scafati

Stefano Baratto

Francesco Carpentieri

Ferdinando Taglialatela

A method of sensing the air/fuel ratio in a combustion chamber of an internal combustion engine that may be easily implemented by a respective low-cost device includes a pressure sensor and a learning machine that generates a sensing signal representing the air/fuel ratio by processing the waveform of the pressure in at least one cylinder of the engine. In practice, the learning machine extracts characteristic parameters of the waveform of the pressure and as a function of a certain number of them generates the sensing signal.

Method and associated device for sensing the air/fuel ratio of an internal combustion engine

A method for determining duty-cycles of respective pulse width modulated (PWM), space vector modulated (SVM) control signals of an inverter, may include storing values of the duty-cycles as a function of a position of the multi-phase electric load in a look-up table. The method also may include determining a phasor angle representing applied sinusoidal voltages. The method also may include determining the duty-cycles as a function of the angle, and storing, in the look-up table, values of two pre-established waveforms relative to at least one duty-cycle as a function of the angle in at least two 60&#xb0; degree angular sectors, by at least, identifying which of six 60&#xb0; angular sectors the angle belongs, calculating a difference between the angle and an angular sector lower bound, and generating values as a function of the identified angular sector of the difference and the two pre-established waveforms stored in the look-up table.

Method and device for determining the duty-cycles of PWM control signals of an inverter

A method estimates variations of position of the rotor of a motor having a plurality of uniformly spaced sensors that generate a position pulse at every rotation by a pre-established angle of the rotor. The method may include generating a first clock signal at a first frequency, generating a second clock signal at a second frequency multiple than the first frequency by a first factor, in each interval between two consecutive position pulses, counting the number of pulses of the first clock signal comprised in the interval, counting the number of pulses of the second clock signal comprised in the interval. The method may also include that each time the number of counted pulses of the second clock reaches the number of pulses of the first clock counted in an interval that precedes the currently considered interval, signaling that the position of the rotor has varied of an angle equal to the ratio between the pre-established angle and the factor.

Method and device for estimating variations of the position of the rotor of an electric motor

A method for estimating the state of a system, as well as an extended Kalman filter (EKF), allows nonlinear mathematical models to be used for describing the system. Accurate precision is provided since the method is based on an EKF technique while using a filter that implements a first degree Stirling approximation formula. The method may be used for estimating position and speed of a brushless motor, and may be implemented in a relative device. Such a device may be introduced in a control loop of a brushless motor of a power steering system for a vehicle to provide a countering torque on the steering wheel based on speed of the vehicle and a steering angle of the vehicle.

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Casoria, Italy

Maurizio Di Meglio