An insulation resistance measuring apparatus designed to calculate a complex impedance of an ac circuit including a measuring resistor, a coupling capacitor, an insulation resistor installed in a vehicle, and a ground capacitance. The insulation resistance measuring apparatus includes a sine wave current applying device which applies an ac signal to the measuring resistor and measures a voltage change appearing at a junction of the sine wave current applying device and the measuring resistor. The ac signal and the voltage change are used to determine the complex impedance. A resistance value of the insulation resistor is calculated as a function of the complex impedance. This structure enables the circuit to be reduced in size.

Various embodiments include a DC switch for disconnecting a DC line. The switch may include: a power semiconductor switch arranged in a current path of the DC line; a first sensor for measuring the input and output voltages; a second sensor for measuring the current flowing through the DC line; and a controller for the power semiconductor switch. The control device is configured to: switch on the DC switch for a first time period; determine the input voltage present; determine the output voltage present at the end of the first time period; determine the current intensity present at the end of the first time period; and determine an inductance and/or capacitance from the determined values.

A method for monitoring impedance of an electrolyzer, a controller and a power supply system are provided. In the method, according to a basic electric energy command, a power supply connected with the electrolyzer is controlled to output a DC component signal used for normal operation of the electrolyzer, and according to an impedance scanning electric energy command, the power supply is controlled to output AC component signals used to monitor the impedance of the electrolyzer. Further, a voltage vector and a current vector outputted by the power supply are acquired, and an impedance value of the electrolyzer is calculated according to the voltage vector and the current vector.

A method for monitoring impedance of an electrolyzer, a controller and a power supply system are provided. In the method, according to a basic electric energy command, a power supply connected with the electrolyzer is controlled to output a DC component signal used for normal operation of the electrolyzer, and according to an impedance scanning electric energy command, the power supply is controlled to output AC component signals used to monitor the impedance of the electrolyzer. Further, a voltage vector and a current vector outputted by the power supply are acquired, and an impedance value of the electrolyzer is calculated according to the voltage vector and the current vector.

A sensor relating to the present invention includes: a first electrode; a second electrode; a first attracting portion positioned between the first electrode and the second electrode and configured to receive conductive abrasion powder contained in a detection region and attracted onto the first attracting portion; a sensing unit for sensing a change in electrical resistance between the first electrode and the second electrode caused by the conductive abrasion powder; and at least one second attracting portion positioned within the detection region and configured to attract the conductive abrasion powder contained in the detection region.

A sensor relating to the present invention includes: a first electrode; a second electrode; a first attracting portion positioned between the first electrode and the second electrode and configured to receive conductive abrasion powder contained in a detection region and attracted onto the first attracting portion; a sensing unit for sensing a change in electrical resistance between the first electrode and the second electrode caused by the conductive abrasion powder; and at least one second attracting portion positioned within the detection region and configured to attract the conductive abrasion powder contained in the detection region.

Disclosed in the present disclosure are an insulation resistance detection circuit, a resistance detection method, a converter and a photovoltaic centrifuge. The insulation resistance detection circuit includes a resistance detection module connected between a positive electrode and a negative electrode of a direct-current bus to be detected. The resistance detection module includes a first resistance bridge and a second resistance bridge arranged in parallel. The first resistance bridge is connected to the positive electrode of the direct-current bus by means of a first sampling resistor R1. The second resistance bridge is connected to the negative electrode of the direct-current bus by means of a second sampling resistor R2, and both the first sampling resistor R1 and the second sampling resistor R2 are equipped with voltage sampling chips. The resistance detection module is configured to calculate an insulation resistance value of the direct-current bus according to voltage values of the two sampling resistors before and after a first switch S is switched.

Disclosed in the present disclosure are an insulation resistance detection circuit, a resistance detection method, a converter and a photovoltaic centrifuge. The insulation resistance detection circuit includes a resistance detection module connected between a positive electrode and a negative electrode of a direct-current bus to be detected. The resistance detection module includes a first resistance bridge and a second resistance bridge arranged in parallel. The first resistance bridge is connected to the positive electrode of the direct-current bus by means of a first sampling resistor R1. The second resistance bridge is connected to the negative electrode of the direct-current bus by means of a second sampling resistor R2, and both the first sampling resistor R1 and the second sampling resistor R2 are equipped with voltage sampling chips. The resistance detection module is configured to calculate an insulation resistance value of the direct-current bus according to voltage values of the two sampling resistors before and after a first switch S is switched.

Systems, devices, and methods are described herein for measuring an impedance of a DUT using an integrated impedance measurement device. A system includes a plurality of measurement circuits, a FFT processor, and a controller. The measurement circuits are coupled to the DUTs. Each measurement circuit is configured to generate a clock signal for a respective DUT, detect a voltage of the respective DUT, and generate first voltage related data using the clock signal and the voltage. The FFT processor is coupled to the measurement circuits. The FFT processor is configured to convert the first voltage related data into second voltage related data using a fast Fourier transform for each measurement circuit. The controller is coupled to the measurement circuits and the FFT processor. The controller is configured to calculate an impedance using the second voltage related data for each measurement circuit and output the impedance to each DUT.

Systems, devices, and methods are described herein for measuring an impedance of a DUT using an integrated impedance measurement device. A system includes a plurality of measurement circuits, a FFT processor, and a controller. The measurement circuits are coupled to the DUTs. Each measurement circuit is configured to generate a clock signal for a respective DUT, detect a voltage of the respective DUT, and generate first voltage related data using the clock signal and the voltage. The FFT processor is coupled to the measurement circuits. The FFT processor is configured to convert the first voltage related data into second voltage related data using a fast Fourier transform for each measurement circuit. The controller is coupled to the measurement circuits and the FFT processor. The controller is configured to calculate an impedance using the second voltage related data for each measurement circuit and output the impedance to each DUT.