scispace - formally typeset
Search or ask a question
Topic

Isolation transformer

About: Isolation transformer is a research topic. Over the lifetime, 8145 publications have been published within this topic receiving 72396 citations.


Papers
More filters
Patent
William E Bray1
19 Sep 1978
TL;DR: In this paper, a self-referencing power converter operates at a high frequency with a low loss, light weight ferrite core transformer, selectively connected across a DC source of rectified AC power, followed by a predetermined time period of disconnect to provide energy transfer by way of transformer flyback.
Abstract: A self-referencing power converter operates at a high frequency with a low loss, light weight ferrite core transformer. The transformer primary is selectively connected across a DC source of rectified AC power to provide energy storage followed by a predetermined time period of disconnect to provide energy transfer by way of transformer flyback. The energy storage cycle begins when the voltage across the primary winding of the transformer does not exceed a predetermined value and the predetermined time period of disconnect has ended. A current sensing circuit senses the current flowing through the primary winding, permitting such current to flow until a power reference is reached. A comparison circuit in the transformer secondary compares a reference voltage with an operating voltage and returns any error voltage to the primary circuit, the error voltage then being used to set the power reference.

56 citations

Journal ArticleDOI
TL;DR: The proposed floating bridge topology eliminates the need for isolation transformer in a dual inverter system and therefore reduces the size, weight, and losses in the system.
Abstract: This paper presents a model predictive control technique applied to a dual-active bridge inverter where one of the bridges is floating. The proposed floating bridge topology eliminates the need for isolation transformer in a dual inverter system and therefore reduces the size, weight, and losses in the system. To achieve multilevel output voltage waveforms, the floating inverter dc-link capacitor is charged to the half of the main dc-link voltage. A finite-set model predictive control technique is used to control the load current of the converter as well as the floating capacitor voltage. Model predictive control does not require any switching sequence design or complex switching time calculations as used for space vector modulation; thus, the technique has some advantages in this application. A detailed analysis of the converter as well as the predictive control strategy is given in this paper. Simulation and experimental results to validate the approach are also presented.

56 citations

Patent
10 Jan 1994
TL;DR: In this article, a modified boost converter accomplishes power transfer to a load with an electrical isolation, a zerovoltage and a zero-current switching, a transformer core resetting mechanism, and component stresses identical to those in the conventional boost converters.
Abstract: A modified boost converter accomplishes power transfer to a load with an electrical isolation, a zero-voltage and a zero-current switching, a transformer core resetting mechanism, and component stresses identical to those in the conventional boost converters. The power converter contains two switching devices, a main one connected in parallel and a secondary one connected in series with a transformer primary winding. A secondary winding of the transformer is connected through an output rectifier to the load. Zero-voltage switching and proper transformer-core resetting are achieved from the resonance that exists between the parasitic capacitance of the secondary switching device and the magnetization inductance of the transformer. A transformer leakage inductance facilitates zero-current switching; thus, reducing the recovery time and current in the output rectifier, and the turn-on switching loss in the conventional main switching device. The switching converter contains a lossless clamping circuit, to limit the voltage stresses across both of the power switching devices to the reflected output voltage appearing across the primary.

56 citations

Patent
13 Apr 1982
TL;DR: In this article, the authors proposed a circuit for bi-directionally bypassing a delta-wye transformer with a balanced phase-to-neutral power line communications signal, using passive components.
Abstract: A circuit for bi-directionally bypassing a delta-wye transformer with a balanced phase-to-neutral power line communications signal, using passive components. The circuit includes a set of three capacitors connected in a wye configuration, each having one side connected to one of the three phase power lines on the delta side of the transformer. The circuit further includes a network connected from the node of the wye configuration of capacitors to the neutral conductor or conductors associated with the power lines on the two sides of the delta-wye transformer. The network includes a single phase transformer, as well as a capacitance connected from the secondary of this transformer to the node of the wye of the delta-wye transformer. The network further includes an inductive reactor connected from the neutral on the wye side of the delta-wye transformer to the node of the wye transformer. Component values of the network are selected so that the network is resonant from the three phase lines on the delta side of the transformer to the node on the wye side of the delta-wye transformer. Further, by selection of the voltage ratio of the single phase transformer, the voltage transformation ratio of the communications signal from the delta side to the wye side is made the same as the corresponding power voltage ratio of the delta-wye transformer.

56 citations

Patent
04 Jun 1998
TL;DR: In this article, a large bandwidth analog isolation circuit is disclosed, where the non-floating side is isolated from the floating side by isolation transformers (11, 12) on the right hand and a multiplier on the left hand.
Abstract: A large bandwidth analog isolation circuit is disclosed. Isolation transformers (11, 12) isolate the nonfloating side on the right hand from the floating side on the left hand. The input signal (1a, 1b) and a high frequency sinusoidal signal (3a, 3b) via a transformer (16) from an oscillator (18) are applied to a multiplier (20). The floating multiplied signal is supplied to a nonfloating multiplier (60). Thereby, the signal (6a, 6b) is multiplied by the high frequency sinusoidal signal (8a, 8b). The nonfloating multiplied signal (9a, 9b) is obtainable and is filtered (67, 68) to send out the output signal (2a, 2b) reproduced from the input signal (1a, 1b). Thus, replica of the input signal is obtained in the nonfloating side.

56 citations


Network Information
Related Topics (5)
AC power
80.9K papers, 880.8K citations
86% related
Voltage
296.3K papers, 1.7M citations
86% related
Electric power system
133K papers, 1.7M citations
84% related
Stator
112.5K papers, 814.8K citations
83% related
Capacitor
166.6K papers, 1.4M citations
82% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202313
202251
202144
2020151
2019211
2018266