Patents
Sitemap › H01 - Basic electric elements › H01F - Magnets; Inductances; Transformers; Selection of materials for their magnetic properties › H01F 29 - Variable transformers or inductances not covered by group
Patents for H01F 29 - Variable transformers or inductances not covered by group (3,889)
06/1999
06/09/1999CN1219276A Controllable inductor
06/09/1999CN1219275A Controllable inductor
06/03/1999WO1999027546A1 Electromagnetic device
06/03/1999CA2309733A1 Electromagnetic device
05/1999
05/25/1999US5907236 Resonance tapped transformer
05/19/1999CN2319910Y Transformer annular coil dual-side electrical brush voltage regulator
05/19/1999CN1216853A Reactive compensation transformer
05/06/1999EP0913916A2 Three-phase transformer
05/05/1999CN1215901A Magnetic core for saturable reactor, multi-output switching regulator and computer having multi-output switching regulator
05/04/1999US5900795 Controllable inductor
04/1999
04/28/1999EP0911842A2 Method for monitoring a tap changer
04/22/1999CA2250625A1 Method of monitoring a tap changer
04/08/1999WO1999017316A2 Induction controlled voltage regulator
04/08/1999WO1999017315A2 A method and an arrangement for regulating a transformer/reactor, and a transformer/reactor
04/08/1999WO1999017314A2 A step-free induction controlled voltage regulator
04/08/1999WO1999017313A2 Magnetic tap changer
04/08/1999DE19844132A1 Magnetic core for a saturable reactor used in a multiple output computer switch regulator
04/08/1999CA2305426A1 Induction controlled voltage regulator
04/08/1999CA2305420A1 Magnetic tap changer
04/08/1999CA2305416A1 A method and an arrangement for regulating a transformer/reactor, and a transformer/reactor
04/07/1999EP0907193A2 Tap changer
04/07/1999EP0906651A2 Rotating electrical machine plants
04/04/1999CA2249520A1 Tap changer
03/1999
03/31/1999CN2312513Y On-load voltage regulation arrangement of transformer made of thyristor and interlock circuit
03/25/1999DE19733321A1 Voltage tap change-over switch for medium voltage transformer
03/24/1999CN1212061A Method and device for automatically switching three-phase voltage for power-saving transformer
03/23/1999US5886507 Controlled ferroresonant transformer
03/17/1999EP0901706A2 A method and a device for reducing third harmonic phenomena in a rotating electric alternating current machine
03/16/1999US5883559 Adjustable asymmetric available saturation flux transformer
03/10/1999EP0900444A1 A controllable inductor
03/10/1999EP0900443A1 A controllable inductor
03/10/1999CN2310420Y Single, three phases leakage flux magnetic path type magnetic voltage regulator
03/09/1999US5880946 Magnetically controlled transformer apparatus for controlling power delivered to a load
02/1999
02/25/1999WO1999009569A1 Controlled ferroresonant transformer
02/17/1999CN2308152Y No-excitation tap changer
02/16/1999CA2151550C Multiphase load control system with switch connected split sources of phase voltage
02/10/1999EP0896269A1 Method and device for automatically switching three-phase voltage for power saving transformer
02/10/1999CN2307342Y Step-up transformer
02/04/1999DE19746574C1 Method of functional monitoring of step switches
01/1999
01/21/1999DE19730289A1 Voltage pick-up shifter for MV transformer
01/20/1999EP0891625A1 Electrical apparatus having electrical conductors mounted in electrical insulation
01/20/1999EP0771518B1 Electrical power control system
01/13/1999CN2304177Y Cross-flux voltage regulator
01/07/1999EP0888662A2 Electromagnetic device
01/07/1999EP0888661A2 An electric high voltage ac machine
01/07/1999EP0888628A1 Transformer/reactor
01/07/1999EP0888627A1 A dc transformer/reactor
12/1998
12/30/1998EP0886785A1 Method for monitoring of tap changers by acoustic analysis
12/30/1998CN2302587Y On-load switch for air-immersed transformer
12/02/1998EP0881647A1 Transformer with controlled interwinding coupling and controlled leakage inductances and circuit using such transformer
12/02/1998EP0807311B1 Device for voltage control
12/01/1998US5844402 In-line buck/boost voltage-regulation systems and apparatus
12/01/1998CA2143264C Zero phase sequence current filter with adjustable impedance
11/1998
11/18/1998EP0878826A2 Use of variable impedance to control coil sputter distribution
11/18/1998EP0878825A2 Use of a variable impedance to control RF coil heating, substrate heating, and film deposition uniformity in a plasma reactor
11/18/1998CN2297786Y Contacting voltage regulator
10/1998
10/29/1998WO1998048432A1 Circuit arrangement for a load transfer switch
10/28/1998CN1197278A Capacity adjustable energy saving transformer of electrical furnace
10/22/1998WO1998047159A1 A controllable inductor
10/14/1998EP0835548A4 Resonance tapped transformer
10/13/1998US5821844 D.C. reactor
10/13/1998US5821739 Electric adjuster
10/13/1998US5821716 Method of controlling a tap changer of a transformer
10/01/1998WO1998043259A1 An arrangement at a conductor on high voltage potential
10/01/1998WO1998043257A1 A core for a controllable inductor and a method for producing thereof
09/1998
09/16/1998CN2291714Y Combined regulation contact voltage regulator
09/16/1998CN1193171A Load adapter switch
08/1998
08/19/1998CN2288549Y Drive for automatic voltage regulator
08/19/1998CN1190820A 静态磁铁发电机 Static magnet generator
08/13/1998DE19804277A1 Dynamo with static permanent magnet(s) for water-power stations, thermal power stations or atomic power stations
08/06/1998WO1998034249A1 Transformer with voltage regulating means
08/06/1998WO1998034244A1 Winding in transformer or inductor
08/06/1998CA2278236A1 Winding in transformer or inductor
08/04/1998US5789907 For controlling the power from an alternating input power source to a load
07/1998
07/30/1998WO1998033256A1 An a.c. current distribution system
07/29/1998CN1189257A Resonance tapped transformer
07/28/1998US5786552 Switching arrangement for load change-over switches of step switches and for selector switches
07/16/1998WO1998031024A1 A controllable inductor
07/09/1998WO1998029929A1 Device and method relating to protection of an object against over-currents comprising over-current reduction and current limitation
07/09/1998WO1998029788A1 Method and device for automatically switching three-phase voltage for power saving transformer
07/09/1998CA2275619A1 Device and method relating to protection of an object against over-currents comprising over-current reduction and current limitation
06/1998
06/30/1998US5773970 Tap changer with tickler coil for arcless tap changing
06/25/1998WO1998027636A1 Device and method relating to protection of an object against over-currents comprising over-current reduction
06/25/1998WO1998027635A1 Device and method relating to protection of an object against over-currents comprising over-current reduction and current limitation
06/25/1998WO1998027634A1 Device and method relating to protection of an object against over-currents comprising over-current reduction
06/25/1998CA2279394A1 Device and method relating to protection of an object against over-currents comprising over-current reduction
06/25/1998CA2275638A1 Device and method relating to protection of an object against over-currents comprising over-current reduction and current limitation
06/25/1998CA2275616A1 Device and method relating to protection of an object against over-currents comprising over-current reduction
06/24/1998EP0849655A2 Alternating current power control device
06/24/1998CN1185600A A. C. electricity control device
06/17/1998EP0748471A4 An electrically controllable inductor
06/02/1998US5760491 Method and circuit for disconnecting a transformer in dependence on whether a load connected thereto requires power, or not
05/1998
05/28/1998WO1998022959A1 Saturation choke coil
05/19/1998US5754034 Electrically controllable inductor
05/13/1998EP0841670A1 Current transformer, trip device and circuit breaker comprising such a transformer
04/1998
04/29/1998CN2280344Y Dry type vacuum load provision switch
04/15/1998EP0835548A1 Resonance tapped transformer
04/08/1998CN2278288Y Dry type vacuum load dividing intermediate voltage-regulating switch
04/08/1998CN1178597A Device for voltage control
03/1998
03/10/1998US5726618 Forward switched mode converter
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