Continental Automotive Systems Corporation

Motorola Corporation

Temic Automotive of North America, Inc.

Patrick A O'Gorman

Dennis L Stephens

Rene Vivanco

Alex Kurnia

Donald J Remboski

Scott W Repplinger

Ken K Foo

Tim Grai

Brian D Conway

Shawn Ferrell

The resonant frequency of a reactive circuit is determined in situ by determining phase angle differences between an A.C. driving voltage applied to a transformer primary winding and an induced alternating current in the transformer secondary winding. The phase angle is determined indirectly by detecting when the driving voltage applied to the primary changes its polarity and when an induced current in the secondary changes its polarity. The time difference between those polarity changes indicates whether the voltage leads or lags the current or is in phase. A driving voltage frequency is adjusted in real time until the phase angle differences disappear. A duty cycle of the driving signal applied to the primary is also adjusted to change the voltage induced in the secondary winding. The duty cycle is adjusted by changing either a phase of primary driving voltages or the duty cycle of primary driving voltages.

Apparatus and method for determining a resonant frequency of an LC circuit in situ, by comparing voltage and current polarity changes

An angular position of a rotating device is detected by sensing and counting high-resolution transitions of high-resolution digital sensors in response to the rotating device rotating; sensing low-resolution transitions of a low-resolution digital sensor in response to the rotating device rotating, the low-resolutions transitions being unevenly spaced apart; determining an angular position of the rotating device in response to determining a number of high-resolution transitions between pairs of low-resolution transitions.

Detecting angular position of a rotating device

Methods and systems for power conversion are disclosed, including receiving at least one interrupt indicative of a transient power condition of the power converter and switching the processor to operate in a second mode from a first mode responsive to the interrupt. The switching enables the processor to allocate greater resources to process a power output parameter of the power converter operating in the transient power condition compared to resources allocated by the processor operating in the first mode to process the power output parameter.

Digitally controlling a power converter

Disclosed herein is an electrical system topology for voltage regulation in a 12-volt vehicle power distribution system. Particularly, a single transistor power converter is configured to operate in both as a traditional voltage regulator mode (i.e., as buck converter to reduce the field voltage applied to an alternator to a value less than that available from the main bus) and as an alternator field current boost converter (i.e., as a boost converter to boost the field voltage applied to an alternator to a value greater than that available from the main bus). The converter may also include a controller that incorporates a thermal model of the alternator to limit the amount of voltage boost applied and/or direct temperature measurement of the alternator or alternator components. Additionally, these two approaches may be combined such that measured temperatures are used to refine the temperature estimated by the thermal estimator.

Single transistor alternator field buck/boost

The position of a rotor of a motor is determined. The motor includes a stator having a plurality of coils. The rotor includes at least one rotating magnetic field device. When the rotor is moving below a threshold speed, the current in the coils is measured. A pre-programmed data structure is accessed. The data structure stores stator currents associated with predetermined rotor positions. A first absolute position of the rotor is determined from the data structure according to the measured current from each of the coils. When the rotor is moving above the threshold speed, one or more rising or falling edges of magnetic field strength associated with the at least one rotating magnetic field device are sensed. At least one timing aspect of the rising and falling edges of magnetic field strength are compared to determine a second absolute position of the rotor.

Apparatus and method for determining angular position

Disclosed herein are a variety of different electrical system topologies intended to mitigate the impact of large intermittent loads on a 12 volt vehicle power distribution system. In some embodiments the intermittent load is disconnected from the remainder of the system and the voltage supplied to this load is allowed to fluctuate. In other embodiments, the voltage to critical loads is regulated independently of the voltage supplied to the remainder of the system. The different topologies described can be grouped into three categories, each corresponding to a different solution technique. One approach is to regulate the voltage to the critical loads. A second approach is to isolate the intermittent load that causes the drop in system voltage. The third approach is to use a different type of alternator that has a faster response than the conventional Lundell wound field machine.

Automotive electrical system configuration

The linear position of a moving mechanical component is determined. A plurality of values of a quantity using a plurality of sensors is sensed and the sensed values are indicative of the linear position of the mechanical component. The plurality of sensed values are converted into a plurality of best linear position estimates concerning the mechanical component. One or more compensations are applied to at least some of the plurality of best linear position estimates. Each of the compensations are applied to account for a relative positioning of one of the plurality of sensors with respect to the others. A plurality of weighting factors associated with each of the plurality of best linear position estimates are determined. The position of the mechanical component is determined using the plurality of best linear position estimates and the plurality of weighting factors.

Position sensing system and method

Methods and systems for detecting an angular position of a rotating device are disclosed, including sensing and counting high-resolution transitions of a high-resolution digital sensor in response to the rotating device rotating; sensing low-resolution transitions of a low-resolution digital sensor in response to the rotating device rotating, the low-resolutions transitions being spaced apart at uneven angles; determining an angular position of the rotating device in response to determining a number of high-resolution transitions between pairs of low-resolution transitions.

Systems and methods for detecting angular position

Methods and systems for detecting an angular position of an electric motor are disclosed, including sending an electrical pulse through a stator coil of the electric motor, determining an approximate angular position of a rotor of the electric motor in response to detecting an timing of a returning electrical pulse from the stator coil, the timing of the returning electrical pulse being indicative of the angular position of the rotor; and determining an accurate position of the rotor in response to sensing a transition of a digital sensor in response to the rotor rotating relative to the stator, the transition being indicative of the accurate position.

Methods and systems for minimizing power loss in generator are disclosed, including providing one or more operating parameters for a generator, and determining an optimal field power and an optimal phase angle, where the optimal field power and the optimal phase angle substantially minimize a power loss in operating the generator at the one or more operating parameters.

Systems and methods for optimizing the operation of a generator

Automotive electrical system

Disclosed herein is an automotive electrical system including a FET based rectifier and method of controlling the FET based rectifier without using either an alternator shaft position sensor or current sensors on each phase of the alternator output to control the switching of the FETs. In accordance with the teachings herein, the voltage and current on the DC bus of the automotive electrical system are sensed and switching of the FETs is controlled by a microcontroller that determines the appropriate switching times based on these sensed parameters.

Active rectification of alternator output without using a position sensor

While a PWM-controlled, FET-switched three-phase motor is operating in a mechanical damping mode, a single current sensor is used to measure current in the motor. When mechanical feedback into the motor exceeds a predetermined threshold, a bank of the FET switches can be closed to provide damping of the mechanical feedback. This causes currents to circulate within the motor, which an external single current sensor cannot measure to determine current load or when the mechanical feedback is no longer a problem. The present invention periodically switches selected switches necessary to sample the current in at least one phase of the motor to determine when the mechanical feedback into the motor is no longer a problem, while preferably also maintaining an average zero voltage vector.

Damping control in a three-phase motor with a single current sensor

The preferred embodiments of the present invention provide a system and method for reducing the battery power required by a handheld device () that incorporates a graphical display (). Graphical display (), display drivers (), LCD controller () and a memory () are optimized such that several pixels of information may be clocked simultaneously when the device is operating in a partial display mode. The optimized circuitry reduces the required refresh clock frequency () and thus the current drain on a device battery () thereby improving device operation time.

Reduced power consumption for a graphics accelerator and display

An apparatus and method for driving a halogen lamp. A driving circuit is provided that is operable near a series resonance frequency. The driving circuit is coupled to the lamp in a series configuration. During startup, the circuit is driven above resonance. After the lamp has warmed up, the circuit is driven substantially at resonance. A controller is coupled to the driving circuit. The controller is operable to control the frequency of operation of the driving circuit.

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Grayslake, IL, United States of America

Patrick A O'Gorman