A current sensing circuit includes an inductor current sensing circuit and a processing circuit. The inductor current sensing circuit senses an inductor current of a direct current to direct current (DC-to-DC) converter to generate a first sensed current signal, wherein an average value of the first sensed current signal is not a constant under different input voltages of the DC-to-DC converter. The processing circuit generates a second sensed current signal, wherein the first sensed current signal is involved in generation of the second sensed current signal, the second sensed current signal is involved in current-mode control of the DC-to-DC converter, and an average value of the second sensed current signal is a constant under said different input voltages of the DC-to-DC converter.

A nested ammeter for measuring the electrical current flowing through a device under test (DUT) can include an input configured to receive an input signal having a frequency within a frequency band and representing the electrical current flowing through the DUT. The nested ammeter can also include an output configured to generate an output voltage representing the electrical current flowing through the DUT. An active shunt can be used as the resistive feedback of the ammeter. A nested active shunt can be used as the resistive feedback element of the active shunt.

A power converting device includes a DC-DC converting circuit, a DC-AC converting circuit, and an insulation detecting circuit. The DC-DC converting circuit is configured to convert a DC input voltage to a DC bus voltage. The DC-AC converting circuit is electrically coupled to the DC-DC converting circuit and configured to convert the DC bus voltage to an AC voltage. The insulation detecting circuit is electrically coupled between the DC-DC converting circuit and the DC-AC converting circuit. The insulation detecting circuit is configured to detect a ground impedance value of the power converting device according to the DC bus voltage.

A device for measuring a current of a three-phase inverter according to an embodiment of the present invention comprises: a current detection element connected to the lower end of one of three lower switches comprising an inverter; a current measurement unit for measuring a current by using the current detection element and the other two lower switches, to which the current detection element is not connected; and a current correction unit for correcting a second current value and a third current value measured using the two lower switches, on the basis of the relationship between a first current value measured using the current detection element and the second and third current values.

An object is to provide a shunt resistor module that is reduced in size, can handle a large current, and can accurately detect current. A shunt resistor module of the present invention includes: a shunt resistor that includes a plurality of resistor bodies having a columnar shape, and electrodes that are located at both ends of each of the plurality of resistor bodies; and a circuit board that includes a plurality of through-holes that can house the plurality of resistor bodies, and a plurality of voltage detection terminals that detects a voltage between the electrodes of the shunt resistor that has been inserted into the plurality of through-holes, and each of the plurality of voltage detection terminals is collected near a center of gravity of the shunt resistor.

The present invention relates to a test shunt clamp device for testing railroad tracks by creating either a hard-wired effect or an impedance. The device has at least two clamps that can be attached to a rail track of a railroad track. Once attached, a toggle switch can be placed in the “HW” or “0.06” position such that the switchable choice between hard-wire and a resistor (that the first and second wires are connected to) delivers a hard-wired effect or a 0.06 ohm impedance to each rail track via a first pointed member of the first clamp attached to the first wire and a second pointed member of the second clamp attached to the second wire.

A current sensor includes a battery terminal portion that is conductive and is fastened to a battery post; a shunt resistor for current detection, which is formed in a plate shape and is electrically connected to the battery terminal portion; and a circuit board that is formed in a plate shape and is electrically connected to the shunt resistor, in which the shunt resistor is erected on a main surface of the circuit board. With this configuration, since the shunt resistor and the circuit board can be arranged so as not to face each other and not confront each other, the influence of heat generated by the shunt resistor can be suppressed.

What is proposed is a method for accurately determining an electric current (I.sub.in, I.sub.in,0) with reduced technical outlay, comprising: connecting a circuit branch (2, 12) in parallel with an inaccurate but current-loadable shunt resistor (R.sub.sh), wherein a reference resistor (R.sub.ref) that is more accurate in comparison with the shunt resistor (R.sub.sh) but less current-loadable is connected into the circuit branch (2, 12), such that the circuit branch (2, 12) branches off in each case at a node point (K) upstream and downstream of the shunt resistor, generating a temporally changeable reference current (I.sub.ref, I′.sub.ref, I″.sub.ref) through the circuit branch (2, 12), measuring the voltages (V′.sub.sh, V″.sub.sh, V′.sub.ref, V″.sub.ref) across the shunt resistor (R.sub.sh) and across the reference resistor (R.sub.ref), determining the current strength (I.sub.in, I.sub.in,0) upstream and downstream of the node point (K).

A measurement arrangement, including a current line, a first measurement location provided on the current line, a second measurement location provided on the current line, and a coolant, wherein the second measurement location is provided at a distance from the first measurement location in order to make it possible to measure a voltage in a measurement section of the current line arising due to a current flowing through the current line, wherein the measurement section is defined between the first measurement location and the second measurement location, and wherein the coolant is of fluid form and at least in areas is in direct contact with the current line in an area between the first measurement location and the second measurement location.

A current sensor includes a battery terminal portion that is conductive and is fastened to a battery post that extends along a first direction; a sensor unit that is located side by side with the battery terminal portion along a second direction that intersects the first direction and is electrically connected to the battery terminal portion to detect a current; and a housing that has an insulating property and embeds the sensor unit, in which the battery terminal portion includes a pair of plate-shaped portions, and the pair of plate-shaped portions are embedded in the housing with end portions on the sensor unit side in the second direction spaced apart from each other along the first direction.