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Showing papers on "Isolation transformer published in 1999"


Journal ArticleDOI
TL;DR: In this paper, the concept of electronic transformers is further extended and explored for its suitability in power distribution systems, and it is shown that a transformer with a conventional grain-oriented silicon-steel core can process three times the power at 1 kHz operating frequency as compared to 60 Hz.
Abstract: A transformer performs many functions such as voltage transformation, isolation and noise decoupling, and it is an indispensable component in electric power distribution systems. However, at low frequencies (60/50 Hz), it is a bulky and expensive component. In this paper, the concept of electronic transformers is further extended and explored for its suitability in power distribution systems. It should be noted that from the input/output behavior, the electronic transformer and the conventional transformer are identical. Possible topologies employing static converters connected on the primary and secondary sides are explored to realize high-frequency operation of the magnetic core. To assist the commutation process, a four-step switching has been developed which does not require the use of snubbers. Reduced size, losses, higher efficiency, and better voltage regulation are some of the advantages of this approach. A 10 kVA design example along with experiment results are discussed. It is shown that a transformer designed with a conventional grain-oriented silicon-steel core can process three times the power at 1 kHz operating frequency as compared to 60 Hz. The proposed method is scalable in voltage/current with the currently available insulated gate bipolar transistor (IGBT) devices connected in series without special snubbers.

320 citations


Proceedings ArticleDOI
14 Mar 1999
TL;DR: In this paper, the authors define the converter voltage transfer ratio taking into consideration the switches' parasitic capacitance and the transformer leakage and magnetizing inductance, and two breadboard models were built and tested utilizing the current fed full bridge topology.
Abstract: The full-bridge isolated current fed converter with active clamp advantages are in its ZVS capability and its well-clamped operation devoid of voltage overshoot on the converter switches and the rectifier diodes. Another relative advantage is that the isolation transformer magnetising current does not have a DC component. An analysis defines the converter voltage transfer ratio taking into consideration the switches' parasitic capacitance and the transformer leakage and magnetizing inductance. The analysis defines the selection criteria for power stage component values. Two breadboard models were built and tested utilizing the current fed full bridge topology. One model was realized as a DC/DC and the other as a single stage PFC. The models' experimental data confirmed calculations.

212 citations


Patent
02 Dec 1999
TL;DR: In this paper, a 3-phase auto transformer with 4 windings per phase is used to power two 6-pulse converter bridges connected in parallel with a large dc filter capacitor.
Abstract: In a 12-pulse converter system a 3-phase auto transformer with 4 windings per phase is used to power two 6-pulse converter bridges connected in parallel with a large dc filter capacitor. The transformer rating is typically about 40% of the dc kW load. The voltage ratio is typically 1:1 so that the average dc output of a multi-pulse converter is generally the same as that of a conventional 3-phase bridge rectifier without transformer, however, ac input harmonic currents are greatly reduced. A small single-phase transformer is used to block unwanted circulating currents between the two 6-pulse converters. Where necessary to further reduce high frequency harmonic currents, a 3-phase ac line reactor may be connected in series with the source of ac power. Where a smaller degree of harmonic reduction is acceptable, only 3 windings per phase are required on the transformer and the small single-phase transformer is eliminated by raising the zero-sequence impedance of the auto transformer by means of an additional magnetic path. This method provides a higher zero-sequence impedance compared to a conventional 3-limb magnetic structure used in most 3-phase transformers. The 1:1 voltage ratio feasible in this invention facilitates retrofit applications, also the concept can be applied to a greater number of parallel converters such as those giving 18-pulse operation.

105 citations


Journal ArticleDOI
TL;DR: In this article, the authors report on test results for a single phase, 60-Hz, 13.8 kV/6.9 kV, 1-MVA high temperature superconducting (HTS) transformer which was completed in February 1998.
Abstract: We report on test results for a single phase, 60-Hz, 13.8 kV/6.9 kV, 1-MVA high temperature superconducting (HTS) transformer which was completed in February, 1998. This transformer models in many ways a full scale section of a 30-MVA HTS commercial transformer design. The transformer windings are cryocooled in the range of 25 K and are made with a low-cost, surface-coated BSCCO-2212 conductor. Heat leaks are reduced using a liquid nitrogen thermal ballast and reservoir. The use of high temperature superconductors can substantially reduce transformer losses, weight, size, noise and potential fire and environmental hazards. Designs promise stable operation through faults without thermal degradation, and at temperatures that allow efficient and reliable refrigeration.

71 citations


Patent
28 Dec 1999
TL;DR: In this paper, a modular transformer arrangement providing power to a multi-level power converter includes a plurality of three phase transformers having delta or extended delta connected primary windings and delta or Extended delta or wye or zig zag wye connected secondary windings.
Abstract: A modular transformer arrangement providing power to a multi-level power converter includes a plurality of three phase transformers having delta or extended delta connected primary windings and delta or extended delta or wye or zig zag wye connected secondary windings and the multi-level power converter has full bridge power modules inputs connected to isolated secondaries of the transformer modules and outputs connected in series and/or in parallel to provide increased voltage and/or current or multiple phases which can be phase shifted with respect to the input to the transformer.

66 citations


Proceedings ArticleDOI
01 Jan 1999
TL;DR: In this article, the viability of applying UHF partial discharge monitoring techniques to an in-service oil-filled power transformer is established, where discharges in oil are shown to radiate the high frequency signals necessary to allow detection.
Abstract: The viability of applying UHF partial discharge monitoring techniques to an in-service oil-filled power transformer is established. Discharges in oil are shown to radiate the high frequency signals necessary to allow detection. On-site pulse injection is used to test the operation of a UHF coupler fitted to the transformer. The effects of on-load tap changing operations are also investigated.

63 citations


Patent
Yogendra K. Chawla1, Graig A. Covert1
22 Jul 1999
TL;DR: In this article, a high-power grounded-drain source follower RF amplifier circuit employs a high voltage MOSFET, which is applied with respect to ground via an isolation transformer whose secondary feeds the signal between gate and source.
Abstract: A high power grounded-drain source follower RF amplifier circuit employs a high voltage MOSFET. The RF signal at the input is applied with respect to ground via an isolation transformer whose secondary feeds the signal between gate and source. The output is taken from the source with respect to drain, which is grounded. A 13.56 MHz 3 KW power amplifier topology with isolated RF input drive for each MOSFET die uses a pair of kilowatt power transistors or KPTs, in which there are multiple large area MOSFET dies, with the drain regions of the dies being formed over a major portion of the die lower surface. The drain regions are in direct electrical and thermal contact with the conductive copper flange. The source and gate regions are formed on the dies away from the flat lower surface. One or more pairs of multi-chip KPTs can be configured to design stable 2.5 KW, 5 KW and 10 KW RF plasma generators at 13.56 MHz. The generators employ a low pass/high pass filter arrangement (diplexer) at the output for low harmonic distortion and dissipative harmonic termination. The terminated high pass filter reduces the gate-to-source differential RF voltage and protects the MOSFETS from damage.

60 citations


Journal ArticleDOI
01 Sep 1999
TL;DR: An analytical solution using the Laplace transform to describe the very fast transient overvoltage (VFTO) in the gas insulated switchgear (GIS) connected directly to a transformer is found in this article.
Abstract: An analytical solution is found using the Laplace transform to describe the very fast transient overvoltage (VFTO) in the gas insulated switchgear (GIS) connected directly to a transformer. The oscillation frequencies, and other properties, are explicitly given in terms of system parameters. The magnitude of VFTO at the transformer is suppressed due to the transformer capacitance, Magnitudes of the initial abrupt voltage change and oscillatory voltage are assessed. The abrupt voltage is larger, but not enough to induce a harmful voltage in the transformer. The oscillatory components may damage the winding insulation at the occurrence of resonance.

57 citations


Patent
Rui Liu1
14 Jan 1999
TL;DR: An asymmetrical power converter as discussed by the authors includes an isolation transformer having series-coupled first and second primary windings providing differing turns ratios therefrom, a first power switch and a first input capacitor series coupled to the first primary winding to form a first circulation path between the isolation transformer and an input of the asymmetric power converter, and a second power switch, a second input capacitor, and the second primary winding connecting the two windings.
Abstract: An asymmetrical power converter and method of operation thereof. In one embodiment, the asymmetrical power converter includes (1) an isolation transformer having series-coupled first and second primary windings providing differing turns ratios therefrom, (2) a first power switch and a first input capacitor series-coupled to the first primary winding to form a first circulation path between the isolation transformer and an input of the asymmetrical power converter and (3) a second power switch and a second input capacitor series-coupled to the second primary winding to form a second circulation path between the isolation transformer and the input.

46 citations


Patent
11 Aug 1999
TL;DR: In this article, a compliance monitoring circuit that generates a constant current output to the isolation transformer of a patient monitoring device is presented, which can be measured and compared against a reference to generate a visible or audible compliance alarm.
Abstract: A method and apparatus for evaluating the connection between the patient monitor and the patient The apparatus is a compliance monitoring circuit that generates a constant current output to the isolation transformer of a patient monitoring device Changes in the impedance of the patient connection cause changes in the output voltage of the constant current generator This voltage can be measured and compared against a reference to generate a visible or audible compliance alarm

44 citations


Proceedings ArticleDOI
14 Mar 1999
TL;DR: In this paper, the authors derived the explicit equation of the bias of the magnetizing current for the first time and provided the transformer design procedures according to the derived equations, and showed that the bias can saturate the transformer core, cause diode reverse recovery problem, and make the active clamp switch lose zero voltage turn-on.
Abstract: In the forward converter with active-clamp reset circuit, the leakage inductance of the transformer and the parasitic capacitances of the switches produce a DC bias of the magnetizing current of the transformer. The DC bias of the magnetizing current could saturate the transformer core, cause diode reverse recovery problem, and make the active clamp switch lose zero voltage turn-on if the bias is not considered in the transformer design. This paper derives the explicit equation of the DC bias of the magnetizing current for the first time and provides the transformer design procedures according to the derived equations.

Patent
04 Oct 1999
TL;DR: In this article, a transformer for switched mode power supplies and the like comprises an input stage transformer section which is designed for very good coupling and very low primary leakage inductance, without regard for insulation above "working insulation" or for interwinding capacitance.
Abstract: A transformer for switched mode power supplies and the like comprises an input stage transformer section which is designed for very good coupling and very low primary leakage inductance, without regard for insulation above "working insulation" or for interwinding capacitance. One or more additional stage transformer sections are optimized for very low interwinding capacitance and very high dielectric isolation. The secondary of the input stage drives the primary of the next stage, so that the transformer stages are in series. Accordingly, the total interwinding capacitance from end to end is very low and the total dielectric isolation from end to end is very high. The secondary of the input stage transformer is isolated from both the input and the output, so it can be grounded as a safety ground. Because the input stage can be designed without regard for capacitance or isolation, it can be smaller, lighter, less expensive and have better thermal and high frequency characteristics, enough so that the transformer as a whole can be smaller, lighter, less expensive and have better thermal and high frequency characteristics than a single stage transformer of comparable rating.

Proceedings ArticleDOI
11 Apr 1999
TL;DR: In this article, the authors describe a computer model which can predict hot-spot temperatures for different types of cooling regimes and transformer winding geometries, which can be used as a design tool, to verify if the hot spot temperature is not too high and to verify the influence of different parameters (winding geometry as well as cooling method or number of radiators) on the temperatures.
Abstract: Power transformers are key components in the distribution of electrical energy, so it is very important to protect them from a breakdown. Hot spot temperature is an important parameter in aging of a transformer so it's both for customers and producers of transformers very useful to have an accurate measurement or computer model prediction of the hot spot temperature. This paper describes a computer model, which can predict hot-spot temperatures for different types of cooling regimes and transformer winding geometries. The program can be used as a design tool, to verify if the hot spot temperature is not too high and to verify the influence of different parameters (winding geometry as well as cooling method or number of radiators) on the temperatures. This knowledge can be shared with the customers allowing improved loading conditions.

Patent
15 Oct 1999
TL;DR: In this paper, the primary and standby AC power signals are passed through an isolation transformer and through an output rectifier to obtain an output DC power signal, respectively, and a switch circuit is provided to connect one or more of the output AC and DC power signals to one or multiple loads of the communications system.
Abstract: A UPS system for communications systems. The UPS system comprises an input stage that generates primary and standby AC power signals. The primary and standby AC power signals are passed through an isolation transformer and through an output rectifier to obtain an output DC power signal. A plurality of output inverters are used to generate a plurality of output AC power signals from the output DC power signal. A switch circuit is provided to connect one or more of the output DC power signals to one or more loads of the communications system.

Journal ArticleDOI
TL;DR: In this paper, a digital technique for protecting power transformers using positive and negative-sequence models of the power system in a fault-detection algorithm is described, while phase voltages and currents at the transformer terminals are used to detect a fault, no information concerning parameters of the transformer and power system is required.
Abstract: Summary form only given as follows. This paper describes a digital technique for protecting power transformers. The technique uses positive- and negative-sequence models of the power system in a fault-detection algorithm. While phase voltages and currents at the transformer terminals are used to detect a fault, no information concerning parameters of the transformer and power system is required. The performance of the proposed technique was studied for a variety of operating conditions using data generated by EMTP simulations. The impact of ratio-mismatch and saturation of current transformers on the performance of the technique was also examined. Results indicate that the proposed technique is stable during these conditions.

Patent
07 May 1999
TL;DR: In this article, a power supply device for a battery-operated electric tool for converting an AC input voltage into a DC output voltage and supplying the output voltage to a power tool is described.
Abstract: A power supply device for a battery-operated electric tool for converting an AC input voltage into a DC output voltage and supplying the DC output voltage to a power tool (78), said power supply device comprising: a housing (76, 82); So as to be electrically connected to the AC input voltage comprises a transformer (12) formed in the housing (76, 82) that reduces a voltage level of the AC input voltage; a first thermal protection means to electrically disconnect the AC input voltage from the transformer (12) (22, 60) which is thermally connected to the transformer (12), if enabled, in response to the exceeding of a predetermined temperature through the transformer (12) ; a second thermal protection means (24) which is connected to the transformer (12) to separate the transformer (12) electrically isolated from the AC input voltage when the temperature of the transformer (12) exceeds a maximum temperature which is greater than the predetermined temperature is; a rectifier (26) electrically connected to the transformer (12) is connected to the through ...

Patent
07 Nov 1999
TL;DR: In this paper, an electronic transformer (10) for lighting inlcudes a rectifier (13) coupled to an inverter (18, C2, C3, Q1, Q2) and a drive transformer (T2, T11).
Abstract: An electronic transformer (10) for lighting inlcudes a rectifier (13) coupled to an inverter (18, C2, C3, Q1, Q2) an output transformer (T1, T10) and a drive transformer (T2, T11). A protection mechanism (VR1, VR2) is responsively coupled to a winding of the output transformer and to a winding of the drive transformer such that the voltage across each of the windings are approximately equal and opposite during normal operation but differ substantially during a short-circuit.

Proceedings ArticleDOI
02 May 1999
TL;DR: The multifunction digital protective relay, used to protect the windings of resistance grounded transformers, can be adapted to continue this form of protection.
Abstract: Transformer ground differential protection relays (device 87G) have been used to protect the windings of resistance grounded transformers. A number of strategies have been utilized with electromechanical relays in the past. With the advent of the multifunction digital protective relay, these strategies can be adapted to continue this form of protection.

Patent
02 Jun 1999
TL;DR: A buck derived isolated DC-DC converter includes a half or full bridge of switching devices which are asymmetrically controlled so that top and bottom switches are opened and closed at mutually exclusive times as mentioned in this paper.
Abstract: A buck derived isolated DC-DC converter includes a half or full bridge of switching devices which are asymmetrically controlled so that top and bottom switches are opened and closed at mutually exclusive times. Primary side and secondary side DC blocking capacitor(s) and a small valued inductor are placed in series with an isolation transformer. A single secondary rectification uncontrolled switch and inductor-capacitor output filter are included. Additionally a voltage clamping circuit is added across the rectifier which includes an active switch which also may be connected to a tap on the output inductor.

Journal ArticleDOI
18 May 1999
TL;DR: In this article, a transcutaneous transformer for an artificial heart system is presented, where the primary and secondary cores are made of ferrite and amorphous magnetic materials respectively.
Abstract: A new geometrical design of a transcutaneous transformer for an artificial heart system is presented in this paper. The primary and secondary cores are made of ferrite and amorphous magnetic materials respectively. The experimental results indicate that it is possible to transmit an electrical power of 20 W which is sufficient to drive the heart pump. With a gap of 5 mm between the coils, its transmission efficiency with the inverter can be up to 90% with a switching frequency 102.5 kHz. Some characteristics of the proposed transformer are also shown and discussed in this paper.

Patent
20 Apr 1999
TL;DR: In this paper, a small-sized heat resistant high voltage transformer and an ignition transformer using a casting resin and an inorganic filler are provided and used to produce an output voltage of 10-35 kV.
Abstract: A small-sized heat resisting high voltage transformer and an ignition transformer using the high voltage transformer are provided and utilize both a heat resistant casting resin and a bobbin, which contain an inorganic filler. The high voltage transformer is capable of producing an output voltage of 10-35 kV and comprises a primary coil, a secondary coil, and a magnetic core, wherein a casting resin is injected into the coil part and subsequently cured. The casting resin and bobbin material used for making the coils have heat distortion temperature of at least 130° C., and contain an inorganic filler. The surface of the bobbin may be pretreated. Thereby, adhesion between a bobbin and a casting resin is enhanced to ensure operating properly under the sever heat cycle condition and provide a small-sized heat resistant high voltage transformer.

Journal ArticleDOI
TL;DR: In this article, a new zero voltage and zero current switching (ZVZCS) full bridge DC-DC converter with transformer isolation is proposed for arc welding machines, which provides load current control capability even under short circuit conditions.
Abstract: A new zero voltage and zero current switching (ZVZCS) full bridge DC-DC converter with transformer isolation is proposed for arc welding machines. The proposed DC-DC converter uses an auxiliary transformer to obtain ZCS for the leading leg, which provides load current control capability even under short circuit conditions. The power rating of the auxiliary transformer is /spl sim/10% or more of the main transformer. The operation is verified by experiments.

Patent
07 May 1999
TL;DR: An isolating cover for mounting on a top of a bobbin of a small-scaled transformer to cover windings and pins provided on the bobbin and isolate them from a frame core of the transformer is presented in this article.
Abstract: An isolating cover for mounting on a top of a bobbin of a small-scaled transformer to cover windings and pins provided on the bobbin and isolate them from a frame core of the transformer. The isolating cover is so designed that it has isolating walls to provide increased creepage distances between any two components on the transformer and therefore prevents a hipot from directly crossing from a high-tension end to a low-tension end on the transformer. The increased creepage distances at all areas of the bobbin enable upgraded quality and reliability of the transformer. The isolating cover can be easily mounted to the bobbin to replace conventional insulating tape for covering the top of the bobbin, and has dimensions that do not exceed an overall volume defined by the bobbin. The transformer with the isolating cover can therefore be manufactured with simplified procedures and at reduced cost.

Journal ArticleDOI
TL;DR: A review of known magnetic-coupled current-sensing techniques is presented and a novel technique is introduced, based on a configuration discussed in a previous paper, to obtain a high bandwidth and very high common-mode rejection current transformer without the need for a Hall effect probe.
Abstract: A review of known magnetic-coupled current-sensing techniques is presented, Subsequently, a novel technique is introduced, based on a configuration discussed in a previous paper. The previous technique made use of a galvanomagnetic device (Hall effect sensor) to sense the magnetization of a current transformer core, so that the sum of the Hall voltage and the voltage across the secondary shunt resistor would yield a faithful copy of the input current. The technique described in this paper makes use of the same principle to obtain a high bandwidth (from DC to 1 MHz) and very high common-mode rejection current transformer, without the need for a Hall effect probe. This is achieved by subtracting the high-frequency components, detected across the secondary shunt resistor, from the voltage across a primary shunt resistor connected in series with the primary of the current transformer. The resulting signal is an accurate image of the transformer magnetizing current, which is then transferred to the secondary side by means of a low-bandwidth isolation amplifier. The high-frequency components are subsequently added, to the amplified and filtered low-frequency components, by means of a third transformer winding, the number of turns of which is chosen to be equal to the gain of the low-frequency amplifier.

Journal ArticleDOI
TL;DR: In this paper, the authors discuss the differences in dielectric design and insulation coordination required for a transformer and their effect on the operation of large power transformers, and discuss the impact of these differences on the performance of large transformers.
Abstract: The dielectric design and insulation coordination required for a transformer are predominantly a function of the requirements of the user. Applicable standards provide both a methodology and criteria through which the industry can then construct and proof test a unit. This permits the user to coordinate the insulation of the transformer with its application in a power system. However, the transformer is then subjected to the actual conditions and operating practices at its installed location. These conditions, and the passage of time, present challenges to the dielectric design different from those of the factory. This paper discusses those differences, and their effect on the operation of large power transformers.

Patent
18 Aug 1999
TL;DR: In this paper, the measuring device is a printed circuit board-based current transformer (1, 2) and the evaluating device is the unit for the early detection of short circuits (20, 40).
Abstract: Protection devices of this type usually have a measuring device and an evaluating device connected downstream. According to the invention, the measuring device is a printed circuit board-based current transformer (1, 2) and the evaluating device is a unit for the early detection of short circuits (20, 40). The printed circuit board-based current transformer (1, 2) is preferably a multi-winding transformer (W1 to W4) and the short circuit detection unit (20, 40) operates on the basis of so-called circle diagram methods which use the instantaneous current (i) and rate of current rise (di/dt) values to detect a short circuit.

Patent
30 Nov 1999
TL;DR: In this article, an uninterruptable power supply includes a rechargeable battery, having a positive terminal and a negative terminal, and a transformer, which is inductively coupled to the battery side transformer via the core.
Abstract: An uninterruptable power supply includes a rechargeable battery, having a positive terminal and a negative terminal, and a transformer. The transformer includes a battery side transformer winding having a first terminal, a second terminal and a third terminal; a load side transformer winding inductively coupled to the battery side transformer winding via a core; and a power supply side transformer winding that is inductively coupled to the battery side transformer winding via the core. An inverter bridge circuit couples the positive terminal of the battery to the first terminal of the battery side transformer winding and couples the negative terminal of the battery to the second terminal and the third terminal of the battery side transformer winding. The inverter bridge circuit includes a switching circuit that forms a bridge circuit that allows current from the battery side transformer winding to flow in only one direction into the battery when the switching circuit is in a first switching state so that current from the power supply slide transformer winding induces an alternating current in the battery side transformer winding that passes through the bridge circuit to generate a direct current that charges the battery when the switching circuit is in the first switching state. The switching circuit also forms an inverter circuit that generates an alternating current from a direct current supplied by the battery when the switching circuit is in a second switching state, thereby inducing an alternating current in the load side transformer winding. A control circuit drives the switching circuit into the first switching state when at least a predetermined power level is supplied to the power side transformer winding. The control circuit also drives the switching circuit into the second switching state when less than the predetermined power level is supplied to the power side transformer winding.

Patent
02 Nov 1999
TL;DR: In this article, a DC-DC converter has an isolation transformer that conveys an alternating voltage of about a first frequency between a primary winding and at least one secondary winding thereof and a four-quadrant inverter, coupled to one of the at least secondary winding, that converts a portion of the alternating voltage into a waveform having about a second frequency that is less than the first frequency.
Abstract: A power supply and a method of operating the same. In one embodiment, the power supply includes: (1) a DC-DC converter having an isolation transformer that conveys an alternating voltage of about a first frequency between a primary winding and at least one secondary winding thereof and (2) a four-quadrant inverter, coupled to one of the at least secondary winding, that converts a portion of the alternating voltage into a waveform having about a second frequency that is less than the first frequency, including: (2a) a bi-directional switch, coupled between an input and an output of the four-quadrant inverter and (2b) a controller, coupled to the switch, that activates the switch to couple the input to the output during a portion of a switching cycle of the alternating voltage to change voltages in the waveform.

Patent
11 May 1999
TL;DR: In this paper, the poles of an inverter are connected in series with the wye connected transformer primary winding which is also connected to the source end of the power line, and a rectifier circuit or a power interface inverter in the DVR and APLC, respectively, is connected to a second secondary winding on the transformer.
Abstract: DVRs and APLCs utilize a single transformer for injection of compensating voltages into an ac power line and for drawing power from or exchanging power with the ac power line. The poles of an inverter are connected in series with the wye connected transformer primary winding which is also connected to the source end of the power line. A first secondary winding is connected to the load end of the power line. A rectifier circuit or a power interface inverter in the DVR and APLC, respectively, is connected to a second secondary winding on the transformer. For high pulse numbers, the rectifier circuit or interface inverter can have additional rectifier bridges or inverter poles connected to additional transformer secondary windings phase shifted with respect to each other. The single transformer can be a load transformer already provided in the power line, thereby further reducing the cost of the arrangement.

Patent
04 Jan 1999
TL;DR: In this article, a current-to-voltage converter with a serially connected partial system (16, 18, 20) has a branch with an input inductance and at least one transistor circuit breaker (T1, T2, T3), and the inductances are applied electrically in series to input voltage U E at least temporarily over the corresponding transistor circuit breakers and produce a balanced voltage between the partial systems.
Abstract: A current-to-voltage converter (10), in particular for high input voltages, comprising a primary side (14), which comprises several serially connected partial systems (16, 18, 20), including respectively at least one transistor circuit breaker (T1, T2, T3) and at least one separate associate transformer primary winding (TP1, TP2, TP3), and a secondary side (22), over which the partial systems (16, 18, 20) are coupled into a common load output (24). In order to make available a current-to-voltage converter having an uncomplicated design and partial systems with improved balanced voltage, the invention herein provides that each of the serially connected partial systems (16, 18, 20) has a branch with an input inductance (L16.1, L18.1, L20.1) and at least one transistor circuit breaker (T1, T2, T3), that the inductances (L16.1, L18.1, L20.1) are applied electrically in series to input voltage U E at least temporarily over the corresponding transistor circuit breakers (T1, T2, T3) and produce a balanced voltage between the partial systems (16, 18, 20), and that one output each of the partial systems (16, 18, 20) is connected with respectively one transformer primary winding (TP1, TP2, TP3) acting as isolating transformer (TR1, TR2, TR3) for power supply.