Abstract: A location engine that estimates the barometric pressure measurement bias of a pressure station reference, such as an airport pressure station, resulting in an improved estimate of the elevation of a wireless terminal. The location engine generates the estimate of bias of barometric pressure by comparing i) the outdoor barometric pressure measured by the airport pressure station at its unknown height above mean sea level (MSL) and ii) the expected outdoor barometric pressure derived from the pressure measurements from an already-calibrated pressure station, while accounting for the known height of the already-calibrated pressure station. The expected outdoor measurements correspond to a derived height above MSL of the airport pressure station. Subsequently, the location engine generates an estimate of the elevation of the wireless terminal by accounting for the estimate of measurement bias of the airport pressure station.

Abstract: System and method for providing electric utilities and utility benchmarking organizations with an integrated real-time outage analytics and benchmarking solution. The system includes a powerful data importing apparatus that allows uploading of outage data from the utilities outage databases, confidential aggregation of utility outage data, real-time comparison of reliability metrics, real-time outage analytics and messaging capabilities. The system includes a communication link for receiving raw outage data uploaded from the outage management systems of participating utilities which couples the data to an analytics server which automatically recalculates standard reliability indices and analytics in real-time. A database server aggregates and stores the data and indices. The analytics server makes data and reports available to user utilities in real-time via the internet while using a unique ID for each user utility to maintain user anonymity and data confidentiality.

Abstract: A building management system (BMS) network interface device including an external communication device configured to provide communication between the BMS network interface and a number of user devices, over a first network. The device further includes a BMS network communication interface for communicating with one or more BMS devices over a second network. The device includes a processing circuit, which includes a number of tools configured to be accessed via a user interface, and further configured to communicate with one or more BMS devices on the second network. The tools include a tailored view tool and a device checkout tool. The tailored view is configured to allow a user to modify the information displayed on the user interface. The device checkout tool is configured to allow a user to select one or more devices on the second network and to modify one or more attributes of the selected devices using the user interface.

Abstract: The present invention relates to a method and a system for identifying energy consumption of electrical appliances. The method uses a string current controller to connect one or more strings of terminal controller string group, wherein each string of terminal controller string group includes one or more terminal controllers connected in series according to priority and each terminal controller is connected to a group of electrical appliances, the string current controller controls, via commands, the power of every terminal controller that are turned on in order of priority in the terminal controller string group, and detects and records the power value, and compares the power value with the rated power of the string current controller, thus, the power of each terminal controller can be monitored and identified in real time to identify and alarm the energy consumption, thereby improving the safety and reliability of the use of electrical appliances.

Abstract: The invention relates to techniques for verifying a nacelle yaw position sensor installed on a wind turbine and for taking restorative action to control the nacelle yaw position. The invention relates to a method performing the comprising determining a first absolute wind direction signal associated with the first wind turbine; determining a second absolute wind signal direction signal associated with the plurality of other wind turbines; comparing the two wind direction signals; and issuing a nacelle yaw position sensor fault signal if the first signal is beyond a predetermined error range of the second signal. A benefit of the invention is that it enables the detection of an inaccurate nacelle yaw sensor without direct measurement or inspection.

Abstract: An energy storage system controller, including: an energy storage system coupled to a power distribution system; and a processor in communication with the energy storage system, wherein the processor executes: a renewables capacity firming algorithm operable for conditioning intermittent power of a renewable energy station using real time and historical input data such that it is made more stable and non-intermittent, optionally utilizing one or more parameter values associated with comparable time periods taking into account one or more factors comprising cloud state; and a peak load shaving algorithm operable for ensuring that the energy storage system is capable of transmitting full power capacity at a predicted feeder peak load time determined by the processor from real time and historical input data; wherein the performance of the renewables capacity firming algorithm and the performance of the peak load shaving algorithm are optimized in parallel.

Abstract: Methods for use in a measurement system. Some embodiments comprise at least one sensor unit and a control unit, wherein the at least one sensor unit is configured to detect a physical quantity and to form a sensor data signal. The method comprises, at the control unit, receiving a data receive signal from the sensor unit, and interpreting the data receive signal to be one of at least the sensor data signal and another data signal, wherein the interpreting is based on an attribute information intrinsic to the data receive signal. Furthermore, there is a sensor unit for use in measurement data acquisition, an apparatus configured to control a measurement data acquisition, a measurement system for use in measurement data acquisition, and a medium incorporating a sequence of operation steps that, when executed, perform a method for use in a measurement system for data acquisition.

Abstract: A system provides indirect current measurement using dynamic sensing of rapidly changing electromagnetic fields. This measurement is achieved using non-contact sensors that are positioned over electric circuit breaker bodies. The system enables the use of readily available, low-cost, mass-produced digital electromagnetic sensors to measure current for circuits in a building. The system may estimate peak electromagnetic field strength from unsynchronized sensor samples. The system may compensate for the low sample rate of the sensors. The system may compensate for smoothing that is performed by sensors so as to be usable as a sensor for a dynamic electromagnetic applications. The system may account for the presence of measurement leakage that causes electromagnetic field distortion. Moreover, the system may infer the electric equipment in use, its time of operation and activity state based on estimates of the alternating electromagnetic field and the use of machine learning or machine intelligence algorithms.

Abstract: An extraction component extracts one or more batteries such that the sum total of the full charge capacity falls within an exclusion target range. An index calculator calculates an index value indicating the usage status of the batteries included among the one or more extracted batteries. An exclusion candidate determination component determines which batteries to exclude from those to be loaned out, on the basis of the ranking of the index value.

Abstract: A circuit detects the type of a power supply driving an LED by analyzing a signal received from the power supply. The circuit controls a behavior of the LED, such as its reaction to a dimmer or to thermal conditions, based on the determined type.

Abstract: An assessment system and method are described that capture indoor temperature measurements and corresponding outdoor temperature measurements in order to determine a thermal efficiency of a structure. The assessment system identifies quiescent periods and trims these periods to eliminate undesirable influences such as auxiliary heating or solar gain. The quiescent periods are then compared to outdoor temperature differences to determine the thermal efficiency of the structure. The system can model the structure's performance metrics, through inferred qualitative and quantitative characterizations including, but not limited to, the building's rate of temperature change as a function of internal and external temperatures, the building's heating, cooling, and other energy needs as they relate to the building envelope, appliances, and other products used at the site and occupant behavior.

Abstract: The methods and apparatus described enable automatic configuration, or commissioning, of controller devices and load control devices through a low voltage communication network controlled by one or more controller devices. These methods and apparatus further enable expansion of the load control system by connection of additional loads and or load control devices and or controller devices which will reinitialize the low voltage communication network and automatically reconfigure the controller devices and load control devices connected to the network.

Abstract: A sensor module for a compressor having an electric motor connected to a power supply is provided. The sensor module includes: a first input connected to a first voltage sensor that generates a voltage signal corresponding to a voltage of the power supply; a second input connected to a first current sensor that generates a current signal corresponding to a current of the power supply; and a processor connected to the first and second inputs. The processor monitors the first and second inputs and, based on voltage measurements from the first input and current measurements from the second input, detects at least one of: (i) an unexpected variation of electric power from the power supply; and (ii) a mechanical malfunction. The processor is disposed within an electrical enclosure of the compressor, the electrical enclosure being configured to house electrical terminals for connecting the power supply to the electric motor.

Abstract: A construction design support apparatus has: an input data acquisition unit; a temporary design unit that creates a plurality of pieces of temporary development surface data and creates temporary panel arrangement data for each piece of the temporary development surface data; a calculation unit that calculates a point value of a development amount for each piece of temporary development surface data and calculates a point value of a cumulative power generation amount for each piece of temporary panel arrangement data; and an extraction unit that extracts a combination of pieces of the temporary development surface data and the temporary panel arrangement data in which the point value of the development amount and the point value of the cumulative power generation amount match a predetermined evaluation condition.

Abstract: The present invention relates to a method and an apparatus for detecting, from a smart plug, an electronic device connected to the smart plug, and more specifically, to a method and an apparatus for detecting a change in an electronic device connected to a smart plug. A method, according to one embodiment of the present invention, is the method for detecting a connected electronic device from the smart plug and comprises the steps of: inspecting whether pre-trained data is present when the an electronic device is connected; inspecting whether the connected electronic device and the pre-trained data match when the pre-trained data is present; a training step of obtaining information on valid power, invalid power, and power factor when the connected electronic device and the pre-trained data do not match; and saving trained data after the training is complete.

Abstract: Technique is provided that enables detection of changes in the condition of a power generation system that generates fluctuating power outputs even in a normal condition thereof. A power generation system management apparatus has: range information management means for managing a condition determination power output range corresponding to a range in which a power output at a predetermined measurement point of the power generation system is to be included with a predetermined probability or higher, the condition determination power output range being determined based on a standard deviation of a plurality of model construction power output values, which is calculated using a representative value of the power output at the measurement point and the model construction power output values, the representative value being calculated from a pseudo system model that is created with a non-parametric method using the plurality of model construction power output values.

Abstract: A first and second set of simulation information of a circuit design may be received. Energy consumption values associated with signals may be calculated for each of the first and second sets of simulation information of the circuit design. The energy consumption values associated with the transitions of the plurality of signals for each time point of a plurality of time points may be aggregated based on when each of the transitions of the signals occurs for each of the first and second sets of simulation information. Furthermore, a possible Differential Power Analysis (DPA) leak may be identified at one of the time points based on a difference in aggregated energy consumption values between the first and second sets of simulation information.

Abstract: The present application relates to an impedance estimation device and estimation method for a power distribution line, and particularly to an impedance estimation device and estimation method for a power distribution line that estimate the impedance of a power distribution line formed of power distribution wires from a pole transformer to a plurality of consumers and a plurality of lead-in wires.

Abstract: One embodiment provides a method including: prior to an initial period of operation of an appliance, storing in memory a first set of characteristics of the appliance; during an initial period of operation of the appliance, learning a second set of characteristics of the appliance; during subsequent operation of the appliance: detecting an adverse operating condition of the appliance; and based on the first set of characteristics, the second set of characteristics and the detected adverse operating condition, determining a corrective action to be taken with regard to the appliance, the corrective action comprising at least one of: switching off the appliance and warning a user of the detected adverse operating condition. Other aspects are described and claimed.

Abstract: A controller may be communicatively coupled to a power supply and may be configured to receive a status signal indicative of whether a level of power delivered by the power supply exceeds a threshold power level. The controller may also be configured to, in response to the status signal indicating the level of power delivered by the power supply exceeds the threshold power level, cause a module power limit of at least one of a plurality of modules disposed in a chassis to decrease, wherein the module power limit of a module defines a maximum amount of power the module may consume from the power supply. The controller may also be configured to, in response to the status signal indicating the level of power delivered by the power supply does not exceed the threshold power level, cause the module power limit to increase.

Abstract: Disclosed herein is an apparatus for updating charging/discharging efficiency factors of an energy storage system. The apparatus includes: a correlation coefficient calculate unit configured to calculate correlation coefficients between n charging/discharging reference values input to the energy storage system during a predetermined update cycle and (n+k) charging/discharging power values measured in the energy storage system after the predetermined update cycle has started, where n and k are natural numbers; a selection unit configured to select n charging/discharging power values corresponding to the n charging/discharging reference values among the (n+k) charging/discharging power values based on correlation coefficients; and an update unit configured to update the charging/discharging efficiency factors set for each power range with n charging/discharging efficiency factors calculated by using the n charging/discharging reference values and the selected n charging/discharging power values.

Abstract: Systems and methods for identifying an island condition in a power distribution system and disconnecting distributed generators in the case of islanding. The systems and methods are used to enable reliable detection of island formation with high false-trip immunity, for any combination of distributed energy resources, and for distributed energy resources using grid support functions.

Abstract: A power control system includes a first inverter power control system and a second inverter power control system coupled in a parallel configuration with the first inverter power control system. Both first and second inverter power control systems may each include an input configured to receive direct current (DC) power; a DC to alternating current (AC) inverter stage configured to receive the DC power input; an anti-islanding relay coupled to the output of the DC/AC inverter stage; and a transition relay coupled to the anti-islanding relay. The transition relay may be configured to route an output of the inverter power control system between one or more onsite back-up loads and an AC grid. The first inverter power control system may be designated as a master that is configured to control the operation of the second inverter power control system designated as a slave.

Abstract: An operating configuration for a power system during a particular time period may be derived from a net load forecast for the power system during the particular time period. The operating configuration may be based on characteristics of power generation units (PGUs) available within the power system (e.g., power generators). The characteristics of a PGU may include a generation trajectory for the PGU that defines, inter alia, power generated by the PGU as the PGU ramps up power production within the power system. The generation trajectory of PGUs may be evaluated in view of the net load forecast to ensure that adequate power resources are available within the power system and avoid ramping scarcity conditions.

Abstract: Disclosed is a method wherein selective voltage binning and leakage power screening of integrated circuit (IC) chips are performed. Additionally, pre-test power-optimized bin reassignments are made on a chip-by-chip basis. Specifically, a leakage power measurement of an IC chip selected from a voltage bin can is compared to a bin-specific leakage power screen value of the next slower voltage bin. If the leakage power measurement is higher, the IC chip will be left in the voltage bin to which it is currently assigned. If the leakage power measurement is lower, the IC chip will be reassigned to that next slower voltage bin. These processes can be iteratively repeated until no slower voltage bins are available or the IC chip cannot be reassigned. IC chips can subsequently be tested according to testing parameters, including the minimum test voltages, associated with the voltage bins to which they are finally assigned.

Abstract: The present disclosure relates to a computer-implemented method for electronic design automation. Embodiments may include providing, using at least one processor, an electronic circuit design at a graphical user interface. Embodiments may further include associating one or more metrics with the electronic circuit design, wherein the one or more metrics include at least one of process metrics, design metrics, issues, library metrics, and custom metrics. Embodiments may further include allowing a user to specify one or more rules that define a key performance indicator for at least a portion of the electronic circuit design, wherein the key performance indicator is based upon, at least in part, the one or more metrics. After a design process associated with the electronic circuit design has been initiated, embodiments may include displaying the key performance indicator at the graphical user interface.

Abstract: An optimal operating configuration for a power system may be derived from a continuous-time model of generation and ramping constraints of power generation units available within the power system. The optimal operating configuration may be leveraged to calculate a valuation metric for power generated by the power generating units. The valuation metric may include costs incurred by the power generating units due to ramping events. In addition, incremental generation and ramping cost metrics may be used to identify power generation units to use in responding to short-term load variations. Power generating units may be selected based, at least in part, on the incremental ramping costs of the power generating units.

Abstract: A method for simulating a power consumption associated with a circuit. Once a netlist describing the circuit and an input stimulus for the netlist are obtained, the netlist is partitioned into multiple circuit blocks. Circuit logic models (CLMs) implemented in a hardware description language (HDL) are then obtained for the multiple circuit blocks and a logic netlist is generated from the multiple CLMs. A power vector for a CLM corresponding to a circuit block is calculated using a logic simulator inputting the logic netlist and the input stimulus. Further, a power consumption value is calculated for the circuit block using a circuit simulator and the power vector. The power consumption associated with the circuit is calculated based on the power consumption values for various circuit blocks.

Abstract: Methods and systems for training an inspection-related algorithm are provided. One system includes one or more computer subsystems configured for performing an initial training of an inspection-related algorithm with a labeled set of defects thereby generating an initial version of the inspection-related algorithm and applying the initial version of the inspection-related algorithm to an unlabeled set of defects. The computer subsystem(s) are also configured for altering the labeled set of defects based on results of the applying. The computer subsystem(s) may then iteratively re-train the inspection-related algorithm and alter the labeled set of defects until one or more differences between results produced by a most recent version and a previous version of the algorithm meet one or more criteria. When the one or more differences meet the one or more criteria, the most recent version of the inspection-related algorithm is outputted as the trained algorithm.

Abstract: Examples of devices described in the present disclosure include a monitoring probe comprising a sensor circuit comprising an electrical sensor, the sensor circuit configured to monitor a level of current flow through an electrical conductor when the electrical sensor is affixed adjacent to the electrical sensor, a wireless transmission circuit coupled to the electrical sensor, the wireless transmission circuit configured to receive the electrical output signal from the electrical sensor, and to wirelessly transmit data from the wireless transmission circuit, and a clip assembly coupled to the electrical sensor, the clip assembly mechanically coupled to the sensor circuit and having a plurality of clip members defining a retention area, wherein the plurality of clip members are configured to receive the electrical conductor within the retention area and exert a force on the conductor therein to affix the electrical sensor at a location adjacent to the electrical conductor.

Abstract: A method and a system (9) for testing a switching installation (30) for power transmission installations are provided. The switching installation (30) comprises a switch (2) which either connects a first side (6) of the switch (2) to a second side (7) of the switch (2) or disconnects it therefrom, and comprises two earthing switches (10, 11). Each of the two earthing switches (10, 11) is provided to either connect the first side (6) or the second side (7) to earth (1) or to disconnect it from earth (1). To test the switching installation (30), a current is generated through the switch (2) and a magnitude of the current through the switch (2) is determined. In this respect, the two earthing switches (10, 11) are closed while the current is generated and while the magnitude of the current is determined.

Abstract: The disclosure relates to systems and methods for managing a wireless powering system for power transfer to electrical devices, providing central management console through a communication network. The wireless powering system comprising at least one wireless power outlet with an integrated communication module and at least one management server and is further operable is further operable to provide location based services when coupled with a software application. The management system, of the current disclosure, is enabling remote health check and maintenance of all of wireless power outlets within the network. Further, the management system allows for complete monitoring of a deployment according to system administrator rights and policy management coupled with command and control functioning to determine allowed/disallowed functionality while transferring powering to an electrical device in a specific venue.

Abstract: A method and apparatus for controlling a reactive power of a generator in a power plant are provided. The method includes: S1, dividing a plurality of power plants into a plurality of plant-plant coordination groups; S2, dividing generators into a first generator and a second generator set; S3, calculating a deviation between a measured voltage and a preset voltage of a central bus; S4, comparing the deviation with a control dead band threshold; S5, establishing a reactive power tracking model if the deviation is greater than the control dead band threshold; S6, establishing a reactive power keeping model; and S7, obtaining sum reactive power adjustments of the generators according to the first reactive power adjustments and the second reactive power adjustments, and obtaining voltage adjustments of buses according to the sum reactive power adjustments.

Abstract: Various examples are provided for parameter estimation of generators. In one example, among others, a method includes collecting data corresponding to a generator using a phasor management unit (PMU) and estimating dynamic parameters of the generator using extended Kalman filtering (EKF) and the collected PMU data. In another example, a system includes at least one application executable in a processing device that obtains operational data corresponding to a generator and estimates a dynamic parameter of the generator using EKF and the operational data. In another example, an EKF estimator includes a dynamics estimator configured to estimate a state variable of a generator, a geometry estimator configured to estimate phasor values associated with the generator, and a Kalman filter gain configured to determine a correction to the state variable.

Abstract: Embodiments of the present invention produce and define a relationship between local voltage and power measurements at a node of an electrical network and system conditions on a remote branch of the network. These local measurements are used to determine an optimal voltage set point at the node that, if realized by a reactive power resource, would affect the flow of reactive power or line current at one or more particular remote branches of the power system in a manner captured by the derived relationship. The change in reactive power required to obtain this voltage set point is also calculated based on local measurements.

Abstract: A method for performing diagnostics on a target transformer includes applying a voltage output of a voltage generator to a winding or phase of the target transformer; controlling the voltage generator to output an AC voltage at a first frequency and then a second frequency and measuring first and second excitation currents flowing into the target transformer associated with the first frequency and second frequency, respectively. The method further includes determining an actual excitation current of the target transformer as a function of both the first and second excitation currents, and comparing the actual excitation current of the target transformer to excitation currents associated with one or more benchmark transformers having known electrical characteristics.

Abstract: A power supply control apparatus, where the power supply control apparatus is configured to control power supply to a cabinet in a data center is presented, where the power supply control apparatus includes a communications module configured to receive an instruction of a network management center, and a controllable switch configured to adjust a capacity of the controllable switch according to the instruction to perform power-on/power-off control on the cabinet. In various embodiments, a power supply control apparatus may receive an instruction of a network management center, and can adjust a capacity of a controllable switch according to the instruction, which enhances power distribution flexibility, and therefore, a workload of changing a switch and a power cable can be reduced, and an engineering related risk can be avoided.

Abstract: A first calculating unit calculates a load current of each distribution facility based on a sending voltage in a power source facility and load information on power consumption facilities in an electrical circuit including the power source facility, the distribution facilities, and the power consumption facilities connected to one another to form the electrical circuit. A second calculating unit calculates the amount of power loss in each distribution facility based on the calculated load current of each distribution facility.

Abstract: Disclosed is an electronic device including a battery, a display, a processor electrically connected with the battery and the display, and a memory which is electrically connected with the processor and stores at least one application, wherein the memory stores instructions which, when executed, cause the processor to monitor power consumption of the at least one application during execution of the at least one application in an off state of the display, and to display, on the display, information indicating whether a value of the power consumption exceeds a threshold selected during a selected time, based on at least a part of a result of the monitoring immediately after the display enters an on state.

Abstract: A storage system and method for handling overheating of the storage system are disclosed. The method comprises determining whether a temperature sensed by a temperature sensor is above a first threshold temperature; and in response to determining that the temperature sensed by the temperature sensor is above the first threshold temperature, lowering a voltage supplied by a power supply to one or more components in the storage system comprising transistors, wherein lowering the voltage supplied to the one or more components reduces temperature by reducing leakage current of the transistors.

Abstract: The present invention provides a detection circuit, which comprises a first detection path and a second detection path for detecting the state of a power source under test. A first current is generated on the first detection path according to power source under test; a second current is generated on the second detection path according to the power source under test. The detection circuit generates a detection signal according to the first current and the second current. The detection signal represents the state of the power source under test.

Abstract: Disclosed are a medium and high voltage grid-connected power generation system, a medium and high voltage grid-connected system, and a control circuitry thereof. The voltage of the medium and high voltage power grid is collected through the control circuitry. A power grid amplitude and a power grid phase synchronization signal are obtained, and then sent to an inverter unit through a communication line.

Abstract: A method and apparatus of validating a test pattern for at-speed testing of at least one integrated circuit, IC, design. The method comprises calculating at least one weighted rise activity, WRA, value for at least one region of the IC design based at least partly on rising gate transitions within the at least one region of the IC design when the test pattern is applied thereto, calculating at least one weighted fall activity, WFA, value for the at least one region of the IC design based at least partly on fall gate transitions within the at least one region of the IC design when the test pattern is applied thereto, and validating the test pattern based at least partly on the WRA value and the WFA value.

Abstract: Disclosed are a method and a system for guiding use of an electronic device.

Abstract: The disclosure relates to a system and method for generating an image by the following steps: obtaining a first image and a second image relating to a subject; obtaining a third image of the subject by a radiology imaging technique; registering the first image and the second image to obtain a first element; calibrating the third image to obtain a second element based on the first element; calibrating the second image based on the second element.

Abstract: A debug device to more accurately compute current consumption or a current consumption quantity from a computer program to be executed in a mobile terminal when a computer program is debugged. The mobile terminal includes a terminal log information acquisition unit configured to acquire terminal log information indicating an operating state of hardware constituting the mobile terminal during debug execution and a current consumption computation unit configured to compute the current consumption or the current consumption quantity of the mobile terminal during debug execution on the basis of the terminal log information and computation information for computing the unique current consumption or the unique current consumption quantity from the operating state of the hardware which is pre-stored.

Abstract: An apparatus for monitoring a signal transmitter for a traffic control signal installation. The signal transmitter has a light-emitting diode. The monitoring apparatus includes: a two-channel measuring device for measuring an actual light intensity of the light which is emitted by the diode and for measuring at least one electrical characteristic variable of the diode, and a control device for operating the signal transmitter depending on the measured actual light intensity and the measured electrical characteristic variable. There is also described a corresponding method, a signal transmitter, a traffic control signal installation and a computer program.

Abstract: Identification of a power source in a multiple power source scenario and characterization of loads. Embodiments herein relate to loads being supplied by multiple power sources and more particularly to identifying the power source supplying power to the load. Embodiments herein disclose a method and system for determining a power source providing power to a load, wherein the load is connected to a plurality of power sources. Disclosed herein is a method and system for characterizing at least one load currently connected to at least one power supply.

Abstract: The present invention provides for a control system for a compressor assembly of an heating, ventilation, and air conditioning (HVAC) system. A control assembly comprises a controller for varying the capacity of a compressor unit of the compressor assembly. The controller determines a first pressure of the compressor unit based on a first operating state of the compressor unit.

Abstract: Systems and methods for measuring the integrity of insulation components in electrical systems. In preferred embodiments, an active sensor is coupled to a test tap of a bushing, the active sensor having an electrical circuit electrically coupled to the test tap, and wherein the electrical circuit includes a high pass filter that divides the electrical circuit into a high frequency bus and a power frequency bus. A grounded high frequency voltage is injected into the test tap via the frequency bus circuit. Resulting voltages and currents may be measured and compared to a reference voltage to determine capacitances and power factors for both the inner and outer sections of the bushing. Once the capacitances and power factors of the bushings are known, grounded and ungrounded high frequency voltages may be injected to determine capacitances and power factors of a connected transformer or reactor.