Abstract: An insulation measurement apparatus includes a path including a first resistor, a capacitor electrically floated from a ground, and a second resistor between a positive to a negative electrode side of a power supply, a first switching element between the power supply positive electrode side and the capacitor, a second switching element between the capacitor and the power supply negative electrode side, a detection section detecting a charge voltage on the capacitor and determining a power supply insulation state, and a voltage setting section executing a power supply voltage measurement mode controlling the first and second switching elements to charge the capacitor for a predetermined time period, and an insulation voltage measurement mode charging a terminal of a positive or negative electrode side of the capacitor via a resistor between the power supply positive or negative electrode and the ground for a predetermined time period.

Abstract: An insulation measurement apparatus includes a path including a first resistor, a capacitor electrically floated from a ground, and a second resistor between a positive to a negative electrode side of a power supply, a first switching element between the power supply positive electrode side and the capacitor, a second switching element between the capacitor and the power supply negative electrode side, a detection section detecting a charge voltage on the capacitor and determining a power supply insulation state, and a voltage setting section executing a power supply voltage measurement mode controlling the first and second switching elements to charge the capacitor for a predetermined time period, and an insulation voltage measurement mode charging a terminal of a positive or negative electrode side of the capacitor via a resistor between the power supply positive or negative electrode and the ground for a predetermined time period.

Abstract: An insulation measurement apparatus includes a path including a first resistor, a capacitor electrically floated from a ground, and a second resistor between a positive to a negative electrode side of a power supply, a first switching element between the power supply positive electrode side and the capacitor, a second switching element between the capacitor and the power supply negative electrode side, a detection section detecting a charge voltage on the capacitor and determining a power supply insulation state, and a voltage setting section executing a power supply voltage measurement mode controlling the first and second switching elements to charge the capacitor for a predetermined time period, and an insulation voltage measurement mode charging a terminal of a positive or negative electrode side of the capacitor via a resistor between the power supply positive or negative electrode and the ground for a predetermined time period.

Abstract: An insulation measurement apparatus includes a path including a first resistor, a capacitor in a state electrically floated from a ground potential, and a second resistor coupled in series sequentially from a positive electrode side of a power supply to a negative electrode side of the power supply, a first switching element provided in a path from the positive electrode side of the power supply to the capacitor, a second switching element provided in a path from the capacitor to the negative electrode side of the power supply, a detection section which detects a charge voltage set to the capacitor and determines an insulation state of the power supply, and a voltage setting section which executes a power supply voltage measurement mode for controlling the first and second switching elements to charge the capacitor by a voltage of the power supply for a predetermined voltage applying time period for measuring the voltage of the power supply, and an insulation voltage measurement mode for charging a terminal o

Abstract: A voltage measurement device includes a first group of switches Q1, Q2, a second group of switches Q7, Q8 and a third groups of switches Q5, Q6. By turning on the third group of switches Q5, Q6, the first group of switches Q1, Q2 are turned on, so that a condenser C1 is charged by voltage impressed between a voltage input terminal A and a voltage input terminal B. While the first group of switches Q1, Q2 are turned off by tuning off the third group of switches Q5, Q6, the second group of switches Q7, Q8 are turned on, so that voltage retained in the condenser C1 is generated between a voltage output terminal G and a voltage output terminal H.

Abstract: A voltage measurement device includes a first group of switches Q1, Q2, a second group of switches Q7, Q8 and a third groups of switches Q5, Q6. By turning on the third group of switches Q5, Q6, the first group of switches Q1, Q2 are turned on, so that a condenser C1 is charged by voltage impressed between a voltage input terminal A and a voltage input terminal B. While the first group of switches Q1, Q2 are turned off by tuning off the third group of switches Q5, Q6, the second group of switches Q7, Q8 are turned on, so that voltage retained in the condenser C1 is generated between a voltage output terminal G and a voltage output terminal H.

Abstract: A control section sets a positive side switching element of a positive side detection section and a negative side switching element of a negative side detection section to ON, thus outputting an ON signal. When the switching elements are set ON, a predetermined current outputted from a positive side constant current source and a negative side constant current source, or a portion of this current, flows through detection resistors. A ground fault decision section decides whether a ground fault has occurred in the positive or the negative side of a direct current power source, based upon the value of an output voltage detected by a positive side voltage detector, or upon the value of an output voltage detected by a negative side voltage detector. Ground faults are accurately detected with a simple structure.

Abstract: A control section sets a positive side switching element of a positive side detection section and a negative side switching element of a negative side detection section to ON, thus outputting an ON signal. When the switching elements are set ON, a predetermined current outputted from a positive side constant current source and a negative side constant current source, or a portion of this current, flows through detection resistors. A ground fault decision section decides whether a ground fault has occurred in the positive or the negative side of a direct current power source, based upon the value of an output voltage detected by a positive side voltage detector, or upon the value of an output voltage detected by a negative side voltage detector. Ground faults are accurately detected with a simple structure.

Abstract: A current detector used in a control system for controlling a motor for driving a vehicle is disclosed, which does not require an especially accurate power circuit, and an accurate measurement result can be obtained by using a cheap power circuit whose accuracy is relatively low. The current detector comprises a detector for outputting a voltage corresponding to a target current, wherein the detector has a current detecting element for detecting the target current; an amplifier for amplifying and outputting the output from the detector; an analog-digital converter for converting the output from the amplifier to a digital data; and a power circuit for supplying an output voltage to both the detector and the analog-digital converter.

Abstract: An apparatus for measuring battery voltage is provided that can detect battery voltage with high accuracy, and also can be miniaturized with cost and noise reduced. The apparatus comprises: a capacitor which is charged to the voltage of each module, switches which connect and disconnect this capacitor and the module, a voltage follower which outputs the voltage across the capacitor, and switches which connect and disconnect the voltage follower and the capacitor. For the aforementioned switches, photo MOSFETs are used. Furthermore, to prevent discharge from the capacitor, a voltage follower is installed. Therefore, by using not a complicated circuit but inexpensive and simple elements, a low cost and miniaturized apparatus for measuring battery voltage is realized.

Abstract: In a propulsion system for hybrid vehicles, etc., a failure detection system that detects the occurrence of failure that obstructs a phase current supplied to an electric motor for propulsion. The direct current of the battery is converted to three-phase alternating current by an inverter and supplied to the electric motor. The controller drive controls the inverter so that the output torque of the electric motor attains a target torque. Each of the phase currents supplied to the electric motor are detected by a current sensor, and provided to a comparator. The comparator compares the value of each of the detected phase currents and the current limit value calculated by the current limit value calculation circuit, and outputs a signal showing that a current phase has abnormally risen. This signal is counted by the counter, and the occurrence of failure is identified based on this count value.

Abstract: The present invention provides a battery voltage measuring device capable of immediately detecting a breakage in the voltage measuring line in a battery voltage measuring device that detects the battery voltage. In blocks formed by connecting a plurality of secondary batteries in series, voltage sensors that detect the voltage of each block are respectively provided. In addition, before these voltage sensors noise filters are provided, and in addition, a measuring line breakage detecting resistor for detecting a breakage in the voltage measuring line is connected in parallel to each block. In a battery voltage measuring device having this type of structure, in the case that the voltage measuring line Q is broken, the voltage values V1 and V2 detected by the voltage sensors 20-1 and 20-2 become voltage values that accompany the resistance ratio of the measuring line breakage detecting resistors 60-1 and 60-2.

Abstract: An AC motor controlling apparatus which can exactly control the torque of an AC motor throughout a motor rotating speed range from low to high.A control mode selecting circuit 13 actuates a switching circuit 19 for allowing an exciting circuit 12 to receive a PWM signal S11 from a current feedback circuit 11 when the rotating speed Nm of the motor 1 is in a higher range, and a PWM signal from an AND gate 14 when it is in a lower range. A power feedback circuit 10 performs a feedback control for matching the power supplied to an inverter circuit 6 to a target power. The current feedback circuit 11 performs a feedback control for matching the phase currents to a target currents.

Abstract: A shift control system for a vehicle transmission with multiple gear trains and a main shaft connected to an engine crankshaft through a clutch. The shift control system allowing shifting without disengaging the clutch.