A method for sensorless control of a separately excited synchronous machine having a rotor includes the following steps: feeding a test signal on a parameter of an electrical current driving the rotor; measuring the parameter of the electrical current driving the rotor on an axis of the coordinate system describing the synchronous machine; determining an error signal by correlating the measured parameter of the electrical current driving the rotor with a temporally delayed test signal which is determined from the fed test signal; and adjusting a rotor angle as a reaction to the error signal if the error signal has a value not equal to zero.

A method for sensorless control of a separately excited synchronous machine having a rotor includes the following steps: feeding a test signal on a parameter of an electrical current driving the rotor; measuring the parameter of the electrical current driving the rotor on an axis of the coordinate system describing the synchronous machine; determining an error signal by correlating the measured parameter of the electrical current driving the rotor with a temporally delayed test signal which is determined from the fed test signal; and adjusting a rotor angle as a reaction to the error signal if the error signal has a value not equal to zero.

A system includes an interface assembly and electronic circuitry. The interface assembly is configured to receive DC power and a self-clocking differential signal comprising a data signal encoded with a clock signal at a clock frequency. The electronic circuitry is configured to recover, from the self-clocking differential signal, the data signal and the clock signal at the clock frequency, and to generate, based on the recovered clock signal at the clock frequency, a synthesized clock signal at a carrier frequency. The electronic circuitry is also configured to use the synthesized clock signal to wirelessly transmit, to an implantable stimulator implanted within a recipient, AC power based on the DC power and forward telemetry data based on the recovered data signal. Corresponding systems, methods, and devices are also disclosed.

A system includes an interface assembly and electronic circuitry. The interface assembly is configured to receive DC power and a self-clocking differential signal comprising a data signal encoded with a clock signal at a clock frequency. The electronic circuitry is configured to recover, from the self-clocking differential signal, the data signal and the clock signal at the clock frequency, and to generate, based on the recovered clock signal at the clock frequency, a synthesized clock signal at a carrier frequency. The electronic circuitry is also configured to use the synthesized clock signal to wirelessly transmit, to an implantable stimulator implanted within a recipient, AC power based on the DC power and forward telemetry data based on the recovered data signal. Corresponding systems, methods, and devices are also disclosed.

A device and method for adjusting an output to an audio port based on a determined sensitivity is provided. The device comprises a processor, an audio port, and an electrical measurement device configured to measure electrical properties of an external device plugged into the audio port over a range of frequencies. Using the electrical measurement device, one or more electrical properties of the external device plugged into the audio port are measured at a plurality of frequencies. A sensitivity of the external device is determined using the using the one or more electrical properties of the external device measured using the electrical measurement device. An output to the audio port is adjusted based on the sensitivity.

A device and method for adjusting an output to an audio port based on a determined sensitivity is provided. The device comprises a processor, an audio port, and an electrical measurement device configured to measure electrical properties of an external device plugged into the audio port over a range of frequencies. Using the electrical measurement device, one or more electrical properties of the external device plugged into the audio port are measured at a plurality of frequencies. A sensitivity of the external device is determined using the using the one or more electrical properties of the external device measured using the electrical measurement device. An output to the audio port is adjusted based on the sensitivity.

An object of the present invention is to provide a technique for monitoring the condition of a device or a target processing object.

A monitoring system according to one aspect of the present invention monitors a device powered by an AC motor and estimates a condition of at least one of the device or a target processing object of the device, and includes a time-series data acquisition unit configured to acquire voltage data relating to a drive voltage of an AC motor; a feature value computation unit configured to analyze a feature value of an abnormal voltage waveform in a time-series waveform of the voltage data; and a state estimation unit configured to estimate the condition based on the feature value of the abnormal voltage waveform.

An object of the present invention is to provide a technique for monitoring the condition of a device or a target processing object.

A monitoring system according to one aspect of the present invention monitors a device powered by an AC motor and estimates a condition of at least one of the device or a target processing object of the device, and includes a time-series data acquisition unit configured to acquire voltage data relating to a drive voltage of an AC motor; a feature value computation unit configured to analyze a feature value of an abnormal voltage waveform in a time-series waveform of the voltage data; and a state estimation unit configured to estimate the condition based on the feature value of the abnormal voltage waveform.

A system frequency detector includes an orthogonal coordinate signal generator generating an orthogonal two-phase voltage signal from a three-phase voltage signal of three-phase alternating current power by converting the three-phase voltage signal into a two-phase voltage signal orthogonal to the three-phase voltage signal, converting the two-phase voltage signal into a voltage signal of a rotating coordinate system, calculating a moving average of the voltage signal of the rotating coordinate system, and performing an inverse transformation of the voltage signal of the rotating coordinate system after calculating the moving average. A frequency calculator calculates an angular frequency based on the two-phase voltage signal, and an arithmetic unit calculates a system frequency of the power system from the angular frequency. The frequency calculator includes a rate limiter in series with the arithmetic unit, the rate limiter limiting a change of the system frequency equal to or greater than a prescribed change rate.

The disclosed embodiments relate to components of a memory system that support timing-drift calibration. In specific embodiments, this memory system contains a memory device (or multiple devices) which includes a clock distribution circuit and an oscillator circuit which can generate a frequency, wherein a change in the frequency is indicative of a timing drift of the clock distribution circuit. The memory device also includes a measurement circuit which is configured to measure the frequency of the oscillator circuit.