A power monitoring circuit and method for detecting deviations in the output of a power supply. The power monitor is configured to detect and measure two different types of deviations: transient deviations short surges or spikes in the current drawn by the device being powered and prolonged deviations over a threshold current that may be intentional, temporary increases in the output of the power supply. The power monitor collects information such as the number of each type of deviation, the duration of each deviation and the peak current describing identified deviations. This collected information can then be used, especially during the development phase, to locate the root cause of the deviation. The components of the power monitor used to detect and measure these deviations may be disabled and enabled as needed.

A power monitoring circuit and method for detecting deviations in the output of a power supply. The power monitor is configured to detect and measure two different types of deviations: transient deviations short surges or spikes in the current drawn by the device being powered and prolonged deviations over a threshold current that may be intentional, temporary increases in the output of the power supply. The power monitor collects information such as the number of each type of deviation, the duration of each deviation and the peak current describing identified deviations. This collected information can then be used, especially during the development phase, to locate the root cause of the deviation. The components of the power monitor used to detect and measure these deviations may be disabled and enabled as needed.

Self-diagnostic method (100) of open-circuit fault, in power switching blocks of a modular inverter comprising a plurality (k=1 . . . n) of blocks (31a, 32a, 33a, 34a, 31b, 32b, 33b, 34b, 31c, 32c, 33c, 34c) in parallel per phase leg (5, 5a, 5b, 5c), and being provided with temperature sensors (6), said method comprising: —sampling and storing (130) temperatures data (I) of said n blocks in a phase leg measured by said temperature sensors at relevant sampling times t.sub.SD with a relevant sampling interval Δt.sub.SD; —comparing (150) said temperature data (I) of each (k) block with previously sampled and stored temperature data (II) of said each (k) block and considering a possible fault (FF) on one of said blocks if the following condition is not fulfilled: (III) where Th is a predefined temperature deviation threshold; or —comparing (250) current temperature data (I) of each (k) block with current average temperature data (VI) and considering a fault (OF) on one of said blocks if the following condition is not fulfilled: (V) where Th.sub.AV is a predefined average temperature deviation threshold. The invention concerns also a test comprising a shoot-through procedure to identify open circuits in a block.

Self-diagnostic method (100) of open-circuit fault, in power switching blocks of a modular inverter comprising a plurality (k=1 . . . n) of blocks (31a, 32a, 33a, 34a, 31b, 32b, 33b, 34b, 31c, 32c, 33c, 34c) in parallel per phase leg (5, 5a, 5b, 5c), and being provided with temperature sensors (6), said method comprising: —sampling and storing (130) temperatures data (I) of said n blocks in a phase leg measured by said temperature sensors at relevant sampling times t.sub.SD with a relevant sampling interval Δt.sub.SD; —comparing (150) said temperature data (I) of each (k) block with previously sampled and stored temperature data (II) of said each (k) block and considering a possible fault (FF) on one of said blocks if the following condition is not fulfilled: (III) where Th is a predefined temperature deviation threshold; or —comparing (250) current temperature data (I) of each (k) block with current average temperature data (VI) and considering a fault (OF) on one of said blocks if the following condition is not fulfilled: (V) where Th.sub.AV is a predefined average temperature deviation threshold. The invention concerns also a test comprising a shoot-through procedure to identify open circuits in a block.

A method for generating an error signal indicating an error type of an error in a multi-phase electrical energy supply network. Measured values describe a current operating state of the network. The measured values are transmitted to a protection device. An evaluating device evaluates every possible loop of the network that can be affected with respect to the recognition of the error type of an error, by using the measured values. In order to be able to more reliably recognize the error type even under different network conditions, the measured values and/or values derived from the measured values are evaluated using at least two different protection criteria, for every possible loop. Each of the protection criteria is suitable for indicating an error type of an error present in the evaluated loop, and the error signal is generated in consideration of all available evaluation results of the protection criteria.

A method for generating an error signal indicating an error type of an error in a multi-phase electrical energy supply network. Measured values describe a current operating state of the network. The measured values are transmitted to a protection device. An evaluating device evaluates every possible loop of the network that can be affected with respect to the recognition of the error type of an error, by using the measured values. In order to be able to more reliably recognize the error type even under different network conditions, the measured values and/or values derived from the measured values are evaluated using at least two different protection criteria, for every possible loop. Each of the protection criteria is suitable for indicating an error type of an error present in the evaluated loop, and the error signal is generated in consideration of all available evaluation results of the protection criteria.

The objective of the present invention is to provide an electric power converting device with which can executes a ground fault detection in a short time with its inexpensive configuration. In one step, the electric power converting device performs level comparison of a difference between output values of low pass filters, with a threshold value −E. If a W-phase is shorted to ground at a time when the U-phase and V-phase lower arm IGBTs are ON and W-phase upper IGBT is ON, the difference between the output values of the low pass filters and becomes small. In another step, a level comparison is made between the absolute value of a difference between the U-phase current value iu and U-phase current command value iu′, and a threshold value F. If the absolute value is lower than the threshold value, the result is determined to be normal, and if the absolute value is greater than the threshold value, the result is determined to be abnormal, because the U-phase is shorted to ground. In another step, a level comparison is made between the absolute value of a difference between the V-phase current iv and the V-phase current command value iv′, and a threshold value F. If the absolute value is lower than the threshold value, the result is determined to be normal, and if the absolute value is greater than the threshold value, the result is determined to be abnormal, because the V-phase is shorted to ground.

The objective of the present invention is to provide an electric power converting device with which can executes a ground fault detection in a short time with its inexpensive configuration. In one step, the electric power converting device performs level comparison of a difference between output values of low pass filters, with a threshold value −E. If a W-phase is shorted to ground at a time when the U-phase and V-phase lower arm IGBTs are ON and W-phase upper IGBT is ON, the difference between the output values of the low pass filters and becomes small. In another step, a level comparison is made between the absolute value of a difference between the U-phase current value iu and U-phase current command value iu′, and a threshold value F. If the absolute value is lower than the threshold value, the result is determined to be normal, and if the absolute value is greater than the threshold value, the result is determined to be abnormal, because the U-phase is shorted to ground. In another step, a level comparison is made between the absolute value of a difference between the V-phase current iv and the V-phase current command value iv′, and a threshold value F. If the absolute value is lower than the threshold value, the result is determined to be normal, and if the absolute value is greater than the threshold value, the result is determined to be abnormal, because the V-phase is shorted to ground.

A power electronics module for a test arrangement for testing a power electronics controller includes: supply connections for supplying energy; at least one load connection for providing at least one electrical connection variable; a supply circuit for providing electrical control voltages; a selection circuit with circuit breakers for switching one of the electrical control voltages onto the at least one load connection of the power electronics module; and an interface for controlling the circuit breakers. The supply connections of the power electronics module are AC supply connections. The supply circuit is a multi-phase circuit for providing a plurality of phase voltages on a plurality of phase conductors. The selection circuit connects a phase conductor to the at least one load connection of the power electronics module.

A power electronics module for a test arrangement for testing a power electronics controller includes: supply connections for supplying energy; at least one load connection for providing at least one electrical connection variable; a supply circuit for providing electrical control voltages; a selection circuit with circuit breakers for switching one of the electrical control voltages onto the at least one load connection of the power electronics module; and an interface for controlling the circuit breakers. The supply connections of the power electronics module are AC supply connections. The supply circuit is a multi-phase circuit for providing a plurality of phase voltages on a plurality of phase conductors. The selection circuit connects a phase conductor to the at least one load connection of the power electronics module.