G01R15/22

Wideband measurement system for mixed-connected capacitive voltage transformer based on optical voltage sensor

A schematic diagram of a wideband measurement system for mixed-connected CVT based on an optical voltage sensor is provided. The wideband measurement system comprises a CVT power frequency measurement section and an optical wideband measurement section. In the optical wideband measurement section, a low-voltage capacitor is connected in series between the low-voltage terminal and the ground terminal of the medium-voltage capacitor in the capacitor voltage divider. An optical voltage sensor is connected in parallel across the terminals of the low-voltage capacitor to measure the wideband voltage signal under test. The wideband measurement system for mixed-connected CVT described in the invention enables the CVT to have wideband measurement capabilities while ensuring the accuracy of conventional CVT power frequency measurements.

Wideband measurement system for mixed-connected capacitive voltage transformer based on optical voltage sensor

A schematic diagram of a wideband measurement system for mixed-connected CVT based on an optical voltage sensor is provided. The wideband measurement system comprises a CVT power frequency measurement section and an optical wideband measurement section. In the optical wideband measurement section, a low-voltage capacitor is connected in series between the low-voltage terminal and the ground terminal of the medium-voltage capacitor in the capacitor voltage divider. An optical voltage sensor is connected in parallel across the terminals of the low-voltage capacitor to measure the wideband voltage signal under test. The wideband measurement system for mixed-connected CVT described in the invention enables the CVT to have wideband measurement capabilities while ensuring the accuracy of conventional CVT power frequency measurements.

CMOS INTEGRATION OF A HIGH BANDWIDTH OPTICALLY ISOLATED CURRENT SENSOR

A galvanically isolated current sensor for power converters is disclosed. The sensor includes a package housing a first integrated circuit (IC), a light emitting layer, an optical waveguide, a photosensing layer, and a second IC. The light emitting layer emits light proportional to a reference current. The optical waveguide modulates the light based on a magnetic field generated by the current to be sensed. The photosensing layer generates a photocurrent representative of the modulated light's intensity. The second IC outputs a sense current based on the photocurrent. The optical waveguide includes polarizers and a Faraday rotator material to effectuate the modulation. Different embodiments of control circuitry for processing the sense current are described, including a flash ADC-based system, a voltage-controlled oscillator with a high-speed counter, and a current-controlled delay line with a low-speed counter.

CMOS INTEGRATION OF A HIGH BANDWIDTH OPTICALLY ISOLATED CURRENT SENSOR

A galvanically isolated current sensor for power converters is disclosed. The sensor includes a package housing a first integrated circuit (IC), a light emitting layer, an optical waveguide, a photosensing layer, and a second IC. The light emitting layer emits light proportional to a reference current. The optical waveguide modulates the light based on a magnetic field generated by the current to be sensed. The photosensing layer generates a photocurrent representative of the modulated light's intensity. The second IC outputs a sense current based on the photocurrent. The optical waveguide includes polarizers and a Faraday rotator material to effectuate the modulation. Different embodiments of control circuitry for processing the sense current are described, including a flash ADC-based system, a voltage-controlled oscillator with a high-speed counter, and a current-controlled delay line with a low-speed counter.