25-01-2013, 12:44 PM
History of Power Electronics for Motor Drives in Japan
[attachment=48429]
Abstract
Power electronics today is one of a wide range of
well defined technologies. The object of this paper is to
review the 50-year history of motor drives in three major
application fields, which are the industrial field, the railway,
and the elevator in Japan. Furthermore, the progress of
power semiconductors and cooling systems, which are
prerequisites for power electronics, are summarized in
historical order. Important inventions from overseas and
their impact on Japanese industries are also introduced.
INTRODUCTION
Power electronics today is one of a wide range of
well defined technologies. It has a key role in the
transformation and adaptation of electrical energy
between the supplier and the user. As the motor drive is
one of major application fields of power electronics, a lot
of developments have been achieved and evolutional
systems have been produced for motor drives in Japan.
The emergence of many kinds of power semiconductors
and the digital control technology such as the use of
microprocessor, made it possible to realize epoch-making
products.
In this paper, the 50-year history of power
electronics for drive systems in Japan is summarized. In
the first place the developments of power semiconductor
devices and cooling systems are stated. Afterwards
various converters and their control methods are sorted
out and classified with historical events. Finally the
developments in three application fields, which are the
industrial field, the railway, and the elevator, are
presented with the introduction of major products.
POWER SEMICONDUCTTOR DEVICES
The invention of the transistor in 1948 revolutionized
the electronics industry. Semiconductor devices were first
used in low power level applications for communications,
information processing, and computers. In 1958, General
Electric developed the first Tyristor, which was at that
time called SCR [1]. With the arrival of Thyristors, the
era of power electronics began. The progress of power
semiconductor devices is summarized in Fig. 1. Since the
production of the 400 V 80 A Thyristor with the wafer of
20 mm’s in diameter in 1961 in Japan, development work
led to a constant improvement in the semiconductor
components and the assorted circuit technology,
Converters for AC motor drive systems
The idea of using a variable-frequency supply to
control the AC motors was old, and rotating frequency
converters had been employed for many years before the
80s. These were used principally in multi-motor mill
drives and in special applications where a high operating
frequency was chosen in order to permit the use of
compact AC motors. Since the 60s, the rotating machine
methods had been supplanted by static conversion
methods.
According to Prof. R. G. Hoft, University Missouri-
Columbia, “The Bibliography on Electronic Power
Converters,” published by AIEE in February/1950
contains a chronological list of references, and it listed
that the first inverter paper was published in 1925 [3]. In
subsequent years, inverter equipments were developed,
using the controlled electronic valve of that era – the grid
controlled, gas-filled tube. In addition to the limitations of
the available valves, circuit configurations themselves had
problems for the stable operations.
Control for AC Motor Drives
A static converter which delivers variable-frequency
power to a motor must also vary the terminal voltage as a
function of frequency in order to maintain the proper
magnetic conditions in the core. The applied
voltage/frequency ratio must be constant in order to
maintain constant flux, and this mode of operation is
known as constant V/f. This open-loop operation of an
induction motor at variable frequency provides a
satisfactory variable-speed drive when the motor is
required to operate at steady speeds for long periods.
When the drive requirements include rapid acceleration
and deceleration, an open-loop system is unsatisfactory,
since the supply frequency cannot be varied very quickly.
When a fast dynamic response is necessary, closed-loop
feedback methods are essential.
CONCLUSION
The 50-year history of power electronics for motor
drives in Japan was stated. Although many important
technologies and basic principles were introduced from
overseas, power electronics for motor drives in Japan has
been thriving with our further efforts and ideas. Power
electronics will be expected to play an important role in
our future society.
[attachment=48429]
Abstract
Power electronics today is one of a wide range of
well defined technologies. The object of this paper is to
review the 50-year history of motor drives in three major
application fields, which are the industrial field, the railway,
and the elevator in Japan. Furthermore, the progress of
power semiconductors and cooling systems, which are
prerequisites for power electronics, are summarized in
historical order. Important inventions from overseas and
their impact on Japanese industries are also introduced.
INTRODUCTION
Power electronics today is one of a wide range of
well defined technologies. It has a key role in the
transformation and adaptation of electrical energy
between the supplier and the user. As the motor drive is
one of major application fields of power electronics, a lot
of developments have been achieved and evolutional
systems have been produced for motor drives in Japan.
The emergence of many kinds of power semiconductors
and the digital control technology such as the use of
microprocessor, made it possible to realize epoch-making
products.
In this paper, the 50-year history of power
electronics for drive systems in Japan is summarized. In
the first place the developments of power semiconductor
devices and cooling systems are stated. Afterwards
various converters and their control methods are sorted
out and classified with historical events. Finally the
developments in three application fields, which are the
industrial field, the railway, and the elevator, are
presented with the introduction of major products.
POWER SEMICONDUCTTOR DEVICES
The invention of the transistor in 1948 revolutionized
the electronics industry. Semiconductor devices were first
used in low power level applications for communications,
information processing, and computers. In 1958, General
Electric developed the first Tyristor, which was at that
time called SCR [1]. With the arrival of Thyristors, the
era of power electronics began. The progress of power
semiconductor devices is summarized in Fig. 1. Since the
production of the 400 V 80 A Thyristor with the wafer of
20 mm’s in diameter in 1961 in Japan, development work
led to a constant improvement in the semiconductor
components and the assorted circuit technology,
Converters for AC motor drive systems
The idea of using a variable-frequency supply to
control the AC motors was old, and rotating frequency
converters had been employed for many years before the
80s. These were used principally in multi-motor mill
drives and in special applications where a high operating
frequency was chosen in order to permit the use of
compact AC motors. Since the 60s, the rotating machine
methods had been supplanted by static conversion
methods.
According to Prof. R. G. Hoft, University Missouri-
Columbia, “The Bibliography on Electronic Power
Converters,” published by AIEE in February/1950
contains a chronological list of references, and it listed
that the first inverter paper was published in 1925 [3]. In
subsequent years, inverter equipments were developed,
using the controlled electronic valve of that era – the grid
controlled, gas-filled tube. In addition to the limitations of
the available valves, circuit configurations themselves had
problems for the stable operations.
Control for AC Motor Drives
A static converter which delivers variable-frequency
power to a motor must also vary the terminal voltage as a
function of frequency in order to maintain the proper
magnetic conditions in the core. The applied
voltage/frequency ratio must be constant in order to
maintain constant flux, and this mode of operation is
known as constant V/f. This open-loop operation of an
induction motor at variable frequency provides a
satisfactory variable-speed drive when the motor is
required to operate at steady speeds for long periods.
When the drive requirements include rapid acceleration
and deceleration, an open-loop system is unsatisfactory,
since the supply frequency cannot be varied very quickly.
When a fast dynamic response is necessary, closed-loop
feedback methods are essential.
CONCLUSION
The 50-year history of power electronics for motor
drives in Japan was stated. Although many important
technologies and basic principles were introduced from
overseas, power electronics for motor drives in Japan has
been thriving with our further efforts and ideas. Power
electronics will be expected to play an important role in
our future society.