Category | Power Electronics Basics

High Frequency Inductive Heating

Posted on 06 February 2014

  Especially in the metal industry it is often necessary to heat objects, possibly for pouring, soldering, case hardening, melting or tempering of these parts. Mostly the heat is generated outside the object and via radiation or convection the heat is transferred to the object or work piece. A much more elegant method is to [...]

Closed loop sensor with flux-gate technology

Posted on 15 January 2014

  Flux gate sensor The flux gate principle is familiar from the flux-gate magnetometers. These were developed during the second world war and used by low flying aircraft to detect submarines. These days fluxgate sensors are used in gyro compasses and in lab equipment to measure remanent magnetism for example. The flux-gate magnetometer can measure [...]

Basics of EMC and EMI

Posted on 27 December 2013

  Originally electronics was synonymous with telecommunications (radio, television, telephony). During operation these electronic devices often produced frequencies and harmonics which interfered with the correct operation of other equipment. These undesirable effects were known as RFI (RFI = radio frequency interference = high-frequency disturbance). Since the last few decades the number of electrical and electronic [...]

Angular Position Sensors (Shaft Angle Transducer)

Posted on 09 December 2013

  Almost every machine or industrial process contains one or more rotating shafts. It is therefore important in most instrumentation systems or control systems to be able to measure the exact shaft angle of a mechanical shaft. This angular data can be used to control position, speed or acceleration of a mechanism. Standard shaft angle [...]

The Skin Effect

Posted on 25 September 2013

  If a DC current I flows through a conductor with diameter d, then the current density is J = \frac{4I}{\pi d^2} (A/mm2) and is constant throughout the cross-sectional area. In the case of an AC current this is not so. We can visualise this by imagining a conductor (fig. 1) as being composed of [...]

Hall Effect Sensors

Posted on 17 September 2013

  Hall effect If we place a current carrying conductor or semiconductor in a perpendicular magnetic field B (fig. 1) then an electric field arises perpendicular to the I-B surface. This effect is known as the Hall-effect. This effect was discovered in 1879 by the American physicist Edwin Herbert Hall. Figure 1. Hall effect Consider [...]

Opto-electronics

Posted on 04 September 2013

  LED (Light Emitting Diode) The light emitting diode (LED) has been used for years as a signal lamp, as number indicator and as a light emitting transmitter in an opto-coupler. In recent years the LED is becoming ever more popular as a light source. The operating principle of the LED rests on the release [...]

Power Module Basics

Posted on 21 May 2013

              Under normal circumstances, power electronics circuitry does not contain one single power semiconductor component but is composed of several components. When discrete devices are used, several of them, including their corresponding heat sinks, must be combined into one assembly to create a bundle of semiconductors that serve to [...]

Basic Considerations for Semiconductor Protection with Fuses

Posted on 23 April 2013

              Solid state devices have progressed through several generations of sophistication since their introduction in the 1940s. Fuse designs have changed to match solid state protection demands. The protection task seems simple - choose a fuse of correct voltage and ampere rating which will protect a solid state device [...]

Sintering Technology

Posted on 17 April 2013

              Sintering combines two fine grained ceramic or metallic materials, usually under high pressure, at temperatures below the melting point of both materials. At a temperature of around 250°C, fine silver powder is sintered under high pressure to form a low-porous silver bond layer between the parts to be [...]