Abstract: A high current source (200) for a test system for testing an electric power device (30) comprises a first plurality of first switchable half-bridges (212) and a second plurality of second switchable half-bridges (222), which are connected in parallel and by means of which a test current is redundantly distributed. A control device (280) is designed to control the first and second half-bridges (212, 222) on the basis of an input signal in such a way that an output signal for the test current, which corresponds to the input signal, is applied across a bridge branch (230) between the first switchable half-bridges (212) and the second switchable half-bridges (222).

Abstract: The present invention relates to a method for determining a state of a capacitive voltage transformer which, on its primary side, comprises a capacitive voltage divider having a first capacitor and a second capacitor. The first capacitor has a high-voltage connection for connection to a high voltage and the second capacitor has a ground connection. A first resonant frequency is determined by way of a plurality of first short-circuit impedance measurements at different frequencies on a secondary side of the capacitive voltage transformer while the high-voltage connection is connected to earth. A second resonant frequency is determined by way of a plurality of second short-circuit impedance measurements at different frequencies on the secondary side of the capacitive voltage transformer while the high-voltage connection is open. A capacitance ratio of the capacitive voltage divider is determined on the basis of the first resonant frequency and the second resonant frequency.

Abstract: A high current source (200) for a test system for testing an electric power device (30) comprises a first plurality of first switchable half-bridges (212) and a second plurality of second switchable half-bridges (222), which are connected in parallel and by means of which a test current is redundantly distributed. A control device (280) is designed to control the first and second half-bridges (212, 222) on the basis of an input signal in such a way that an output signal for the test current, which corresponds to the input signal, is applied across a bridge branch (230) between the first switchable half-bridges (212) and the second switchable half-bridges (222).

Abstract: The present invention relates to a method for determining a state of a capacitive voltage transformer which, on its primary side, comprises a capacitive voltage divider having a first capacitor and a second capacitor. The first capacitor has a high-voltage connection for connection to a high voltage) and the second capacitor has a ground connection. A first resonant frequency is determined by way of a plurality of first short-circuit impedance measurements at different frequencies on a secondary side of the capacitive voltage transformer while the high-voltage connection is connected to earth. A second resonant frequency is determined by way of a plurality of second short-circuit impedance measurements at different frequencies on the secondary side of the capacitive voltage transformer while the high-voltage connection is open. A capacitance ratio of the capacitive voltage divider is determined on the basis of the first resonant frequency and the second resonant frequency.

Abstract: The invention relates to a method for personal protection during high-voltage testing on a test object, the method comprising the steps of outputting a high-voltage alternating current for the test object by means of a high-voltage generation device, which has a high-voltage transformer for generating the high-voltage alternating current. The method further has the steps of determining a curve over time of at least one electrical variable at the high-voltage transformer during the output of the high-voltage alternating current, and ending the output of the high-voltage alternating current on the basis of the curve over time of the at least one electrical variable.

Abstract: An apparatus for locating partial discharges in a medium-voltage or high-voltage operating equipment comprises a signal detection device for detecting an electrical signal variable of the operating equipment, a filter device for low-pass filtering of the detected electrical signal variable dependent upon a filter cut-off frequency, a time detection device for detecting a signal propagation time of the low-pass-filtered electrical signal variable, and a comparison device for comparing the detected signal propagation time detected dependent upon the filter cut-off frequency with a reference propagation time for a charge pulse conducted through the operating equipment in order to determine a location of the partial discharge in the operating equipment dependent upon the result of the comparison. Also provided is a method for locating a partial discharge in medium-voltage or high-voltage operating equipment, in particular, using the apparatus.

Abstract: A method (60) for determining resistances (R1, R2, R3, RN) on a voltage level of a multiphase transformer (10) comprising one winding (u, v, w; U, V, W) for each phase comprises injecting a particular first current into the particular winding (u, v, w; U, V, W); recording a particular first voltage caused by the injected first currents in the plurality of phases; injecting a particular second current into the particular winding (u, v, w; U, V, W), wherein the particular injected second current differs from the particular injected first current in at least one of the plurality of phases; recording a particular second voltage caused by the injected second currents in the plurality of phases, and determining the resistances (R1, R2, R3, RN) on the voltage level on the basis of the injected first and second currents and the recorded first and second voltages. An apparatus (70) for determining resistances (R1, R2, R3, RN) on a voltage level of a multiphase transformer (10) is also proposed.

Abstract: A testing device for an apparatus of an energy system which has inputs that can be connected in a conductive manner to at least one current transformer and at least one voltage transformer. The testing device is designed to apply a first test signal to a secondary side of the voltage transformer and, at the same time, to apply a second test signal to a primary side of the current transformer.

Abstract: The following steps are performed in order to test a tap changer of a transformer which tap changer is designed to change a transmission ratio of the transformer: generating a test signal which is supplied to a winding of the transformer and to the tap changer, repeatedly actuating the tap changer in order to change the transmission ratio with each actuation, determining a curve of an electrical measurement variable (I; I1; I2) of the transformer over time (t) for each actuation of the tap changer depending on the test signal filtering the curves in order to prevent at least one of the curves from being output outputting the filtered curves.

Abstract: The following steps are performed in order to test a tap changer (20) of a transformer (5; 6) which tap changer is designed to change a transmission ratio of the transformer (5; 6): generating a test signal which is supplied to a winding (1-3; 10) of the transformer (5; 6) and to the tap changer (20). Repeatedly actuating the tap changer (20) in order to change the transmission ratio with each actuation. Determining a curve of an electrical measurement variable (I; I1; I2) of the transformer (5; 6) over time (t) respectively during the step of actuating the tap changer (20) depending on the test signal. automatically illustrating the curves (41, 42) in a temporally-superimposed manner.

Abstract: In a method, operation of an electric power system which has a power utility automation system (1981-1984, 1991-1994) is monitored. The power utility automation system (1981-1984, 1991-1994) comprises a plurality of intelligent electronic devices (IEDs) (1981-1984, 1991-1994) communicating via a communication network. During operation of the electric power system, properties of the electric power system are monitored, the monitored properties comprising monitored data messages which are transmitted by the plurality of IEDs (1981-1984, 1991-1994) over the communication network. The monitored data messages are evaluated based on configuration information for the power utility automation system (1981-1984, 1991-1994) to detect a critical event. An alert signal is generated in response to detection of the critical event.

Abstract: The aim of the invention is to improve the efficiency and handling of a test device (4) for testing a protection relay (2). This is achieved by a method and a test device (4). A signal (S) is generated in a test device (4), and the signal (S) is applied to the protection relay (2). An adaptation device (X) which can be found in the test device (4) is supplied with a supply voltage (Uv) by an accumulator (5), and the adaptation device (X) supplies a signal generator (G) with an intermediate voltage (Ux), said signal generator generating the signal (S). The use of an accumulator (4) allows fuel-supplied power units to be obviated. The use of an adaptation device (X) allows the supply voltage (Uv) of the accumulator (5) to be converted into small intermediate voltages (Ux) and the small currents of the accumulator (5) to be converted into high currents in order to supply the signal generator (G) for example.

Abstract: The present method relates to a method for checking a multi-pole electrical circuit breaker. The multi-pole electrical circuit breaker comprises a plurality of poles (101-103). Each of the plurality of poles (101-103) comprises a first connection (121-123) and a second connection (131-133). Closing the particular pole (101-103) makes it possible to electrically connect the first connection (121-123) of the particular pole (101-103) to the second connection (131-133) of the particular pole (101-103) via the pole. In the method, a plurality of micro-ohm measurements are carried out at the plurality of poles (101-103), while the plurality of poles (101-103) are earthed on both sides in a P-P-P-E configuration. A contact resistance of one of the plurality of poles (101-103) is determined on the basis of the plurality of micro-ohm measurements.

Abstract: The following steps are performed in order to test a tap changer (20) of a transformer (5; 6) which tap changer is designed to change a transmission ratio of the transformer (5; 6): generating a test signal which is supplied to a winding (1-3; 10) of the transformer (5; 6) and to the tap changer (20). Repeatedly actuating the tap changer (20) in order to change the transmission ratio with each actuation. Determining a curve of an electrical measurement variable (I; I1; I2) of the transformer (5; 6) over time (t) respectively during the step of actuating the tap changer (20) depending on the test signal. automatically illustrating the curves (41, 42) in a temporally-superimposed manner.

Abstract: The present method relates to a method for checking a multi-pole electrical circuit breaker. The multi-pole electrical circuit breaker comprises a plurality of poles (101-103). Each of the plurality of poles (101-103) comprises a first connection (121-123) and a second connection (131-133). Closing the particular pole (101-103) makes it possible to electrically connect the first connection (121-123) of the particular pole (101-103) to the second connection (131-133) of the particular pole (101-103) via the pole. In the method, a plurality of micro-ohm measurements are carried out at the plurality of poles (101-103), while the plurality of poles (101-103) are earthed on both sides in a P-P-P-E configuration. A contact resistance of one of the plurality of poles (101-103) is determined on the basis of the plurality of micro-ohm measurements.

Abstract: The following steps are performed in order to test a tap changer (20) of a transformer (5; 6) which tap changer is designed to change a transmission ratio of the transformer (5; 6): generating a test signal which is supplied to a winding (1-3; 10) of the transformer (5; 6) and to the tap changer (20). Repeatedly actuating the tap changer (20) in order to change the transmission ratio with each actuation. Determining a curve of an electrical measurement variable (I; I1; I2) of the transformer (5; 6) over time (t) for each actuation of the tap changer (20) depending on the test signal. Filtering the curves (41, 42) in order to prevent at least one of the curves (41, 42) from being output. Outputting the filtered curves (41; 42).

Abstract: In order to check a switching operation of an electric switch (1-3), a movement of a movable switching element (1) of the electric switch (1-3) is sensed during the switching operation. For that purpose, a marking element (11) is used, the marking element (11) having a magnetization pattern comprising a plurality of magnetic markings. A path length (9) of a relative movement between the marking element (11) and a sensor (12) is determined.

Abstract: The present invention relates to a measuring device (10) for measuring a resistance of a switching contact (5) of an electrical circuit breaker (1). The measuring device (10) comprises a high-current generating unit (11) for generating a measurement current for the resistance measurement, and a measuring unit (12) for registering a measurement signal at the circuit breaker (1) during the opening or closing of the switching contact (5), and for determining a time-based resistance course of the switching contact (5) during opening or closing, in dependence on the measurement current and the measurement signal.

Abstract: A test device (1) for testing power engineering equipment comprises at least one connection socket (4) which is electrically connected to an overvoltage protection arrangement (2). The overvoltage protection arrangement (2) comprises at least one overvoltage protection element (5) and is configured such that the at least one overvoltage protection element (5) is exchangeable.