The disclosure relates to accurately determining a DC energy signal, such as a DC current or DC voltage, which may be particularly useful when controlling a formation/testing current of a battery cell during formation and/or testing. In the battery formation/testing context, a current sensor is used to measure the current of the battery cell, which is used as a feedback signal for controlling the current to achieve a target current. The transfer function of the current sensor is used to improve the accuracy of the current measurement. Because the transfer function can be regularly determined during formation/testing, a lower-cost current sensor with relatively poor temperature coefficient may be used. Any change in the gain of the current sensor may be detected by the transfer function determination and corrected for. Therefore, high current control accuracy may be achieved at lower cost.

The present disclosure generally describes a system that includes a heater, a power converter including a power switch, and a controller. The power converter is in communication with the heater and is operable to apply an adjustable voltage to the heater. The controller is in communication with the power switch to control the voltage output of the power converter based on at least one of a load current and a detected voltage at the heater. The controller operates the power switch to adjust the voltage output of the power converter.

A power calculation apparatus includes a power measurement unit configured to measure alternating-current electric power input to a converter unit to obtain measured power, power consumption estimation units configured to estimate power consumption on motor axes of corresponding motors, respectively, using parameters concerning the motors, to obtain estimated power for each motor axis, and a power consumption calculation unit configured to distribute the measured power obtained by measurement according to a ratio in accordance with the estimated power obtained by estimation to calculate power consumption for each motor axis.

A method of estimating a root mean square (RMS) of an alternating current (AC) voltage is provided. The system includes a rectifier configured to rectify the AC voltage and a controller configured to derive a delayed AC voltage by delaying the rectified AC voltage by a preset delay time. The controller is configured to estimate a root mean square (RMS) of the AC voltage based on the rectified AC voltage and the delayed AC voltage.

A method of estimating a root mean square (RMS) of an alternating current (AC) voltage is provided. The system includes a rectifier configured to rectify the AC voltage and a controller configured to derive a delayed AC voltage by delaying the rectified AC voltage by a preset delay time. The controller is configured to estimate a root mean square (RMS) of the AC voltage based on the rectified AC voltage and the delayed AC voltage.

A current sensor circuit comprises multiple resistive circuit elements of different values of electrical resistance arranged between at least one input terminal of the current sensor circuit and an output terminal; a first plurality of switching circuits coupled between the input terminal and the resistive circuit elements, wherein each switching circuit of the first plurality of switching circuits includes a pair of transistors connected in series; at least one drive amplifier including an output and an input connected to the output terminal; and a second plurality of switching circuits, each switching circuit including a first switch terminal coupled to the at least one drive amplifier output and a second switch terminal coupled to a common connection of a pair of transistors of the first plurality of switching circuits.

A current sensor circuit comprises multiple resistive circuit elements of different values of electrical resistance arranged between at least one input terminal of the current sensor circuit and an output terminal; a first plurality of switching circuits coupled between the input terminal and the resistive circuit elements, wherein each switching circuit of the first plurality of switching circuits includes a pair of transistors connected in series; at least one drive amplifier including an output and an input connected to the output terminal; and a second plurality of switching circuits, each switching circuit including a first switch terminal coupled to the at least one drive amplifier output and a second switch terminal coupled to a common connection of a pair of transistors of the first plurality of switching circuits.

A voltage detecting apparatus includes a signal extracting circuit configured to extract a coupled signal from a signal output by a power amplifier configured to amplify a signal output by a radio frequency (RF) circuit, and a voltage detecting circuit configured to detect a detection voltage from the coupled signal and provide the detection voltage to the RF circuit. The voltage detecting circuit configured to vary the detection voltage in response to an input control signal.

A voltage detecting apparatus includes a signal extracting circuit configured to extract a coupled signal from a signal output by a power amplifier configured to amplify a signal output by a radio frequency (RF) circuit, and a voltage detecting circuit configured to detect a detection voltage from the coupled signal and provide the detection voltage to the RF circuit. The voltage detecting circuit configured to vary the detection voltage in response to an input control signal.

The present disclosure provides apparatuses and methods for measuring power for a lighting control system. The includes a lighting control module configured to cause a transmission of a quantity of electrical power to a lighting circuit of a light fixture electrically connected to the lighting control module, a detector circuit positioned in the lighting control module, and a controller in electrical communication with the detector circuit. The controller is specially programmed to correlate a quantity of electrical power transmitted to the lighting circuit to the response of the lighting circuit. The controller is further programmed to determine a power correction factor based on the correlation between the quantity of electrical power transmitted and the response. The power correction factor is configured to alter the response of the lighting circuit to a predetermined value.