A device for detecting a leakage current generation condition in a universal serial bus (USB) interface including at least one pull-up circuit connected to the at least one power pin, and a port controller configured to detect at least one impedance between a ground pin and at least one power pin, detect a leakage current generation condition in the at least one power pin based on the at least one impedance detected, and activate a detection signal in response to the leakage current generation condition being detected, the port controller configured to detect the at least one impedance by controlling the at least one pull-up circuit to pull up the at least one power pin and detecting a voltage of the at least one power pin may be provided.

A method and a photovoltaic inverter for determining the insulation resistance of a photovoltaic system relative to ground are provided. The voltage required for the measurement can be provided by an intermediate circuit in the form of an intermediate circuit voltage and a measuring device is designed to actuate an input short-circuit switch for short-circuiting a DC input with an AC disconnector open, as a result of which the intermediate circuit voltage can be applied to the DC input in the reverse direction. The measuring device is configured to record measured voltages with a switch of a voltage divider open and closed, and to determine the insulation resistance from the measured values of the two measured voltages recorded with the switch of the voltage divider open and closed.

A monitoring device for monitoring an impedance of a protective conductor. The monitoring device has a first voltage divider for connection to a voltage source including a series connection to a first resistor and a second resistor. The second resistor has a resistance value which corresponds to a threshold value for the impedance of the protective conductor. A second voltage divider includes a series connection to a third resistor and a bridge diode and a connection to the first resistor at a first end of the third resistor and connectable to a second end of the third resistor and to the protective conductor. A measuring device is provided for the detection of a bridge voltage between a first node and a second node if the impedance of the protective conductor is greater than the value of the second resistor.

A monitoring device for monitoring an impedance of a protective conductor. The monitoring device has a first voltage divider for connection to a voltage source including a series connection to a first resistor and a second resistor. The second resistor has a resistance value which corresponds to a threshold value for the impedance of the protective conductor. A second voltage divider includes a series connection to a third resistor and a bridge diode and a connection to the first resistor at a first end of the third resistor and connectable to a second end of the third resistor and to the protective conductor. A measuring device is provided for the detection of a bridge voltage between a first node and a second node if the impedance of the protective conductor is greater than the value of the second resistor.

A method determines an insulation resistance of the high-voltage network in an electric or hybrid vehicle, in which a controllable continuous voltage source connected to the body and to a single first terminal of a high-voltage battery of the vehicle is provided, a first resistor being connected in series to the source between the single first terminal and the body and a second resistor being connected in series between the first resistor and the source, consecutive voltage setpoint values are applied between the body and the single first terminal, a measurement signal of the voltage at the terminals of the second resistor is acquired for each setpoint value, adaptive filtering of the signal is carried out and an estimate made, in a recursive manner, of a vector of the filter transfer function coefficients, providing an update of the filtering coefficients, the insulation resistance being determined based on the estimate.

A method determines an insulation resistance of the high-voltage network in an electric or hybrid vehicle, in which a controllable continuous voltage source connected to the body and to a single first terminal of a high-voltage battery of the vehicle is provided, a first resistor being connected in series to the source between the single first terminal and the body and a second resistor being connected in series between the first resistor and the source, consecutive voltage setpoint values are applied between the body and the single first terminal, a measurement signal of the voltage at the terminals of the second resistor is acquired for each setpoint value, adaptive filtering of the signal is carried out and an estimate made, in a recursive manner, of a vector of the filter transfer function coefficients, providing an update of the filtering coefficients, the insulation resistance being determined based on the estimate.

The invention relates to an electric circuit arrangement (20) for the functional testing of a monitoring device (4) for a power supply system (2), the electric circuit arrangement (20) having a test resistance (R.sub.f1, R.sub.f2) which is switched between an active conductor (L.sub.1, L.sub.2) of the power supply system (2) and ground (PE) and has a settable actual resistance value (R.sub.x). In this context, a bidirectional cascade (12) consisting of field-effect transistors as test resistances (R.sub.f1, R.sub.f2) and an analog control (10) for the continuous-value setting of the actual resistance value (R.sub.x) to a predefined target resistance value (R.sub.0) are provided. Furthermore, the invention relates to a modular circuit arrangement (60) consisting of several electric circuit arrangements (20) according to the invention, each of the electric circuit arrangements (20) being assigned a different active conductor (L.sub.1, L.sub.2) of the electric power supply system (2), and a central control unit (50) being implemented for controlling and monitoring the electric circuit arrangements (20).

The present disclosure relates to a motor vehicle on-board network with a first voltage circuit for supplying electric power to an environment sensor system with a first electrical voltage, wherein an insulation monitor is provided for the first voltage circuit to monitor the insulation resistance of the first voltage circuit.

The present disclosure relates to a motor vehicle on-board network with a first voltage circuit for supplying electric power to an environment sensor system with a first electrical voltage, wherein an insulation monitor is provided for the first voltage circuit to monitor the insulation resistance of the first voltage circuit.

The present invention discloses an insulation detection circuit and a detection method thereof for a two-way on-board charger. The detection circuit comprises an inverter circuit, a first Y capacitor connected between an output live line and a ground line of the inverter circuit, a second Y capacitor connected between an output neutral line and the ground line of the inverter circuit, a live line sampling circuit and a neutral line sampling circuit which are connected with the output live line and the output neutral line of the inverter circuit, and a controller. The controller determines an insulation state of the two-way on-board charger according to two sampling voltages.