Patents by Inventor Stefano Baratto

Stefano Baratto has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7791304
    Abstract: 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° degree angular sectors, by at least, identifying which of six 60° 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.
    Type: Grant
    Filed: January 16, 2008
    Date of Patent: September 7, 2010
    Assignee: STMicroelectronics S.R.L.
    Inventors: Francesco Pirozzi, Maurizio Di Meglio, Stefano Baratto
  • Patent number: 7786686
    Abstract: A method is for estimating an angular position of a rotor of a motor having position sensors along the circumference of a stator and generating digital signals that switch each time the rotor crosses certain angular positions. The method includes storing rotor angular positions at every digital signal switching, and determining for each rotor revolution a time interval elapsed between a current and a precedent switching edge of the signal generated. The method also includes estimating the angular position during a current rotor revolution by identifying which position sensor generated the last detected switching edge. The corresponding angular position and the time interval elapsed between two consecutive rotor crossings, through a same angular position, correspond to a sum between the angular position and a product between a fraction of the time interval elapsed from the corresponding precedent switching edge multiplied by 360° and a number of polar pairs.
    Type: Grant
    Filed: January 22, 2008
    Date of Patent: August 31, 2010
    Assignee: STMicroelectronics S.R.L.
    Inventors: Giuseppe D'Angelo, Giovanni Moselli, Stefano Baratto
  • Patent number: 7714571
    Abstract: 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.
    Type: Grant
    Filed: March 22, 2007
    Date of Patent: May 11, 2010
    Assignee: STMicroelectronics S.R.L.
    Inventors: Francesco Pirozzi, Maurizio Di Meglio, Stefano Baratto
  • Patent number: 7659685
    Abstract: 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.
    Type: Grant
    Filed: August 2, 2007
    Date of Patent: February 9, 2010
    Assignee: STMicroelectronics S.R.L.
    Inventors: Nicola Cesario, Stefano Baratto, Maurizio Di Meglio
  • Publication number: 20090033259
    Abstract: 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.
    Type: Application
    Filed: August 2, 2007
    Publication date: February 5, 2009
    Applicant: STMicroelectronics S.r.I.
    Inventors: Nicola Cesario, Stefano Baratto, Maurizio Di Meglio
  • Patent number: 7459890
    Abstract: A control circuit is for an electric power plant including an asynchronous generator of an AC voltage, a motor to rotate a rotor of the asynchronous generator as a function of a first control signal of a developed motor torque, and a bank of capacitors coupled to the asynchronous generator and having a total capacitance varying as function of a second control signal. The control circuit may include a monitor circuit to monitor at least one parameter of the AC voltage, and a control signal generator circuit cooperating with the monitor circuit to generate the first and second control signals by soft-computing techniques both as a function of the frequency and of a representative value of an amplitude of the AC voltage to make the AC voltage have a desired amplitude and frequency.
    Type: Grant
    Filed: November 23, 2005
    Date of Patent: December 2, 2008
    Assignee: STMicroelectronics S.R.L.
    Inventors: Stefano Baratto, Francesco Giuffré, Umberto Macri, Mario Lavorgna, Giuseppe D'Angelo, Giovanni Moselli
  • Publication number: 20080180046
    Abstract: A method is for estimating an angular position of a rotor of a motor having position sensors along the circumference of a stator and generating digital signals that switch each time the rotor crosses certain angular positions. The method includes storing rotor angular positions at every digital signal switching, and determining for each rotor revolution a time interval elapsed between a current and a precedent switching edge of the signal generated. The method also includes estimating the angular position during a current rotor revolution by identifying which position sensor generated the last detected switching edge. The corresponding angular position and the time interval elapsed between two consecutive rotor crossings, through a same angular position, correspond to a sum between the angular position and a product between a fraction of the time interval elapsed from the corresponding precedent switching edge multiplied by 360° and a number of polar pairs.
    Type: Application
    Filed: January 22, 2008
    Publication date: July 31, 2008
    Applicant: STMicroelectronics S.r.l.
    Inventors: Giuseppe D'ANGELO, Giovanni Moselli, Stefano Baratto
  • Publication number: 20080169780
    Abstract: 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° degree angular sectors, by at least, identifying which of six 60° 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.
    Type: Application
    Filed: January 16, 2008
    Publication date: July 17, 2008
    Applicant: STMicroelectronics S.r.l.
    Inventors: Francesco Pirozzi, Maurizio DI Meglio, Stefano Baratto
  • Publication number: 20070241741
    Abstract: 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.
    Type: Application
    Filed: March 22, 2007
    Publication date: October 18, 2007
    Applicant: STMicroelectronics S.r.l.
    Inventors: Francesco Pirozzi, Maurizio Di Meglio, Stefano Baratto
  • Publication number: 20060132103
    Abstract: A control circuit is for an electric power plant including an asynchronous generator of an AC voltage, a motor to rotate a rotor of the asynchronous generator as a function of a first control signal of a developed motor torque, and a bank of capacitors coupled to the asynchronous generator and having a total capacitance varying as function of a second control signal. The control circuit may include a monitor circuit to monitor at least one parameter of the AC voltage, and a control signal generator circuit cooperating with the monitor circuit to generate the first and second control signals by soft-computing techniques both as a function of the frequency and of a representative value of an amplitude of the AC voltage to make the AC voltage have a desired amplitude and frequency.
    Type: Application
    Filed: November 23, 2005
    Publication date: June 22, 2006
    Applicant: STMicroelectronics S.r.I.
    Inventors: Stefano Baratto, Francesco Giuffre, Umberto Macri, Mario Lavorgna, Giuseppe D'Angelo, Giovanni Moselli