Active solid-state devices (e.g. – transistors – solid-state diode – Regenerative type switching device – With integrated trigger signal amplification means
Patent
1996-03-08
1998-09-15
Whitehead, Jr., Carl W.
Active solid-state devices (e.g., transistors, solid-state diode
Regenerative type switching device
With integrated trigger signal amplification means
257213, 257691, 257901, H01L 2974
Patent
active
058083278
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to an AC power controller which operates with at least two reverse-connected series semiconductor regions. The semiconductor regions, which are each provided with an electron donor (source), an electron sink (drain) and an electrode (gate) which controls the flow of electrons, have the same characteristic curves as FETs. According to contemporary knowledge, they also have an internal body diode, dictated by the technology, which operates in the inverse mode.
BACKGROUND INFORMATION
A known power circuit-breaker (WO 93/11608) operates with two FETs reverse-connected in series. In such a power circuit-breaker, the release element of the component acting as a relay is arranged electrically in parallel with a semiconductor element having two FETs reverse-connected in series. The component can interrupt a line train to be protected by means of interrupter contacts. In such a case, the semiconductor element is set such that its internal impedance has a low value when there is a specific control voltage across a control electrode and an operating voltage across working electrodes that are situated in the direction of continuity in the line train. The internal impedance of the semiconductor element rises abruptly as the voltage across the working electrodes rises. In the event of an increase in the internal impedance, voltage is applied to the release element arranged in parallel, which voltage results in tripping of the circuit-breaker.
Electrical installations have to be connected to and isolated from an electricity supply. In the case of mechanical switches, there are optimized solutions which in practice satisfy certain technical requirements. For example, in the case of drives, motor protective circuit-breakers provide overload protection and short-circuit protection. It is generally desirable in the case of protective switchgear, which includes power circuit-breakers, motor protection circuit-breakers and line protection circuit-breakers, to rapidly detect overload currents that occur, in particular short-circuit currents, and to limit them to small values and finally to disconnect them.
Mechanical protective switchgear has the disadvantages of contact wear, frequent maintenance and a comparatively slow switching time in the event of a short circuit, as well as comparatively low temporal accuracy of the switching instance.
In contrast, semiconductor switches can operate without any wear and switch rapidly; they have low switching losses and they can be controlled in a variable manner. On the other hand, the disadvantages of semiconductor switches are: high costs, large space requirements and comparatively high forward losses.
In general terms, it is frequently desirable to limit alternating currents rapidly to specific values, so that over-currents become tolerable or to allow time for disconnection. Semiconductor elements can also be operated in such a way that they reduce current all the way down to the point of disconnection.
SUMMARY OF THE INVENTION
The present invention is based on the object of developing an advantageous AC power controller using semiconductor technology. The invention is, at the same time, based on the knowledge that the previously discussed devices and elements can be designed as AC power controllers in the broadest sense.
According to an embodiment of the invention, the above-mentioned object is achieved by an AC power controller semiconductor regions with reverse-connected in series. The gate-source voltage for a respective semiconductor region in the forward direction is set to be large enough for a desired limiting of the drain-source current to be established. For the semiconductor region in the inverse mode, the respective gate-source voltage is only set to be large enough for the body diode to remain de-energized. In other words, the second semiconductor region has at this current a voltage drop such that its body diode is still de-energized.
The invention is based on the knowledge here that the forward losses in relev
REFERENCES:
patent: 5225741 (1993-07-01), Auld, Jr. et al.
Maier Reinhard
Mitlehner Heinz
Zierhut Hermann
Siemens Aktiengesellschaft
Whitehead Jr. Carl W.
LandOfFree
AC controller does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with AC controller, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and AC controller will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-91173