EPE Journal Volume 01-1 
 You are here: EPE Documents > 02 - EPE Journal Papers > EPE Journal Volume 01-1 
EPE Journal Volume 01-1 - Editorial
EPE Journal Volume 01-1 - Papers
EPE Journal Volume 01-1 - The Association



 EPE Journal Volume 01-1 - Editorial 

The EPE President's Address  [Details]
By J. C. Sabonnadière

The Editorial of the EPE Journal Volume 1 N°1, "The EPE President's Address", written by Prof. J. C. Sabonnadière, the President of EPE Association.


 EPE Journal Volume 01-1 - Papers 

Power Electronics: The Silent Revolution, its Technical Importance and Economical Impact  [Details]
By F. D. Althoff

The title of this paper is certainly not very new, imaginative or original.

Silent Electronics? Thingking of a rock band with tens of kW of music power electronics or a 1000 kW short-wave radio station spreading political slogans makes one shudder and doubt this description. But this paper is dealing striuctly with industrial electronics. However, thinking of the squealing noise emitted by some frequency controlled drive system or variable frequency chopper, the word "silent" meaning quiet is, at least sometimes the wrong description.

Unfortunately, power electronics is "silent" in the negative sense of "not noticed" by the public and not heard by the decision makers. There is an old saying: Silent babies are getting less milk, less attention and less love; silent babies stay weaker and grow less than their louder brothers.

Nowadays large, important and expensive technologies are made, carried through, fed or starved out not only by engineers and their managers but by the media, politicians, administrations, by the public and ultimately the tax payer.

Power electronics must be heard, promoted and sponsored according to its paramount technical and economic importance. Therefore, we must speak up, we must explain, we must be heard.

Let's trigger a few more thoughts with this worn title: Unnoticed revolutions are either no revolutions or particularly dangerous ones.

If we continue as before, if we stay silent and don't wake up any body, our domain "power electronics" might soon be governed by firms and nations from outside Europe.

30 Years Space Vectors, 20 Years Field Orientation, 10 Years Digital Signal Processing with Controlled AC-Drives, a Review (Part 1)  [Details]
By W. Leonhard

The dynamic interactions of AC-machines are far more complex than those of DC-machines and important quantities are not directly measurable. This has given rise to considerable difficulties in designing high performance AC-drive controls. About 20 years ago, they were overcome by the emergence of new methods of control, using moving frames of reference determined by the angular position of flux waves, hence called field orientation. Their application requires extensive on-line signal processing that can only be realised economically with microprocessors or special digital hardware.

The paper presents a review of this evolution, which has matured in less than 2 decades from research studies to a universally accepted method for controlling AC-machines. The method of field orientation has proved to be well adaptable to all types of power converters and AC-machines; modifications and extensions to include self-tuning and adaptive features are possible. It now seems to be generally accepted that field orientation in one of its many forms is the most promising control method for high performance AC-drives.

Part II of this paper can be read in EPE Journal Volume 1991-2.

A PWM Current-Source Inverter for high Quality Drives  [Details]
By G. Amler

With fast microprocessors and suitable switching devices such as GTO thyristors CSI-drives are considerably improved. Sinusoidal input and output currents are replacing the block-shaped currents of sequentially commutated inverters and a sophisticated control permits fast dynamic response. To achieve this goal, the resonant circuit consisting of the capacitors at the inverter terminals and the machine inductances has to be kept under close control. With an online calculation of the PWM switching times, not only the voltages but also the currents are maintained very close to the reference value, even at limited switching frequency. Measurements at the machine side converter show the distinctive features of this drive system at various operating points.

Commutation Modes in Resonant Converters - Control and Safety in DC-DC Conversion  [Details]
By J. Roudet; J. P. Ferrieux

In this paper the authors present the two different soft commutation modes for DC-DC power conversion applications and resonant systems.

Spontaneous commutations become possible in a resonant converter.
Two basic functions are studied: thyristor for a zero-current-switching mode (ZCS) and dual-thyristor for a zero-voltage-switching mode (ZVS).
The dual-thyristor mode is more suited for a voltage inverter structure whereas the thyristor mode is usually used in current inverters.

For this last mode a control strategy is proposed which ensures safe operation in voltage inverter.

Then, this control is applied on a series resonant DC-DC converter operating in ZCS mode. In that case the switching frequency is below the resonant frequency.
The theoretical study is carried out with snubbers (series inductances) which don't disturb the normal operation for all the loads.

The Innovation in the Field of High Voltage Bipolar Transistor  [Details]
By P. Aloïsi

The power mosfet technology gives a lot of new possibilities in the low and medium voltage application field:
- High switching speed for low volume, efficient applications,
- Power switches easy to design and to drive.
In the range of medium and high voltage and medium and high power application, the same type of requests come up for the bipolar devices:
* Increase of the device ruggedness by increasing the safe operating area's
* Capability to sustain accidental overloads or energy discharge from the parasitic inductances
* Improvement the device switching speed to increase the working system frequency
* Narrowing the electrical parameter distribution
* Capability to drive products easily
And also, improve the best characteristics of the bipolar devices:
* The saturation voltage
* Decrease the die cost by an easy manufacturing and process control.

Protection of IGBT Modules in Inverter Circuits  [Details]
By F. Eschrich

For many applications new, light weight, small size, low accoustic noise and high efficiency inverters are demanded. For these applications several new power semiconductor devices have been developed. One of thee devices is the IGBT (Insulated Gate Bipolar Transistor). With the low saturation voltage of the Bipolar Transistor and the high switching speed characteristic of the MOS-FET, it is the most interesting device at the moment. A VVVF (variable voltage / variable frequency) inverter is taken as an example for overvoltage and overcurrent protection of IGBTs.

Specific Integrated Circuits for Power Electronics  [Details]
By P. Mathys; J. L. Van Eck

This paper shows through examples that microelectronics plays an important role in modern power electronics devices. The main requirements of power electronics designers are reliability, performances, easy maintenance, user friendly interface, ruggedness to electromagnetic, mechanical and thermal constraints. Besides the development of new types of power semicondfuctors and the improvement of existing ones, integrated circuits have increased the performance and reliability of the control of power equipments. Ana&log integrated circuits are used for simple, but high speed functions like controlling switched mode power supplies. Microprocessors have brought the versatility of programmed logic, the ability to implement complex control algorithms, and to handle communications with the operator and with different parts of an equipment. To avoid the saturation of a microprocessor by the more and more nbumerous tasks they have to perform, one can resort to multiprocessor systems, to Digital Signal Processors (DSP) or to wired logic. Those solutions are rather complex and increase the volume. An interesting alternative is the resort to Application Specific Integrated Circuits (ASIC). The design effort and cost to develop an ASIC are now affordable for every power electronics manufacturer. Using ASIC considerably reduces the number of chips, boards, connectors, testing operations and hence increases reliability, noise immunity, speed, temperature range and mechanical strength.

Vision of the future for electronic test and measurement solutions  [Details]
By Hewlett Packard Brussels

Since the early 1970's automated measurement systems have become easier to integrate. The development of the Hewlett Packard Interface Bus (HP-IB) led to this area of systems integration. After HP-IB was adopted as an industry standard (IEEE 488, IEC 625), the course was firmly set for the next two decades. The system integrator's choice of products grew with the increasing number of vendors offering products with this industry-standard interface. Systems could be scaled more easily to meet the user's application requirements. IEEE-488 instruments have met the needs in the past but for some applications the 1 MHz data rate and lack of support for multiple masters controllers have limited their application. Today the pressure on instrument manufacturers to downsize instrumentation and standardize on hardware, operating systems and instrument language architectures is growing.


 EPE Journal Volume 01-1 - The Association 

EPE Conference, Association, Journal... - History, why, how, what for...  [Details]
By G. Maggetto; P. Lataire

This article, written by the founding members Prof. Maggetto and Prof. Lataire, and gives an introduction into the bigger framework of the EPE Conference, the Association, the Journal, etc....

EPE and the International Scene  [Details]
By R. M. Davis; P. Evans

This article, written by Mr. R.M. Davis, founding member of EPE Association and Mr. P. Evans, member of EPE's International Steering Committee, gives an insight in EPE Association and the international scene.