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Tap into a totally clean source of AC energy, free from distortion and
high-frequency noise. Revolutionary waveform shaping technology
enables highly precise compensation, providing a pure energy source
with 230 V AC
±2% (or 120 V AC ±2%). Connect audio or video
equipment for a drastic improvement in sound and picture quality.
Monitor output power, input/output voltage, and input/output distortion
on the built-in meter.
Almost every electrical device used in an household converts the AC
supplied by the outlet into a DC current for powering its internal circuits.
This task is performed by a rectifier. As shown in photograph
, the
rectifier load current has a pulse waveform with a large current flowing
momentarily in the vicinity of the voltage peak. This causes a voltage
drop, resulting in clipping of the voltage waveform, as shown in
photograph
.
A clipped waveform with a high amount of distortion contains many
unwanted frequency components, or harmonics. When passing through
the PS-1200V, the deformed waveform is restored to its original sine
wave pattern, as shown in photograph
.
Photo Current waveform of
rectified load
Photo
Voltage waveform of AC
line (distortion approx. 3%)
Photo
PS-1200V output wave-
form (distortion approx. 0.2%)
Power supply waveform and PS-1200V output waveform
The Clean Power Supply components from
Accuphase are revolutionary products that remove
noise and impurities from the AC power line and
improve signal quality by continually monitoring
and shaping the power supply waveform. They
have been widely acclaimed for drastically
improving the sound and picture quality of audio
and video equipment. The PS-1200V is a further
upgraded version of the predecessor model PS-
1200. The circuitry has been optimized to fulfilleven higher performance demands, and the power
transformer that forms the heart of the system is
now a high-performance type with even more
muscle. Because the PS-1200V is a high-power
version of the PS-500V, a single unit can deliver
enough power to cover the requirements of almost
any high-quality system.
The PS-1200V uses waveform shaping technology
to turn the power from a regular AC outlet into a
highly pure sine waveform for use as a stable anduncontaminated energy source of A/V components.
To achieve this, the PS-1200V constantly monitors
the input voltage waveform and adds or subtracts
exactly the required amount of correction. The
compensation required by this innovative technique
typically is only a fraction of overall power. The
PS-1200V therefore operates with high efficiency
and produces little heat, allowing it to be designed
as a fairly compact and lightweight unit. Since it
contains no oscillators or switching circuitry, the
PS-1200V itself does not act as a source of
spurious high-frequency noise.
AC Voltage Stabilizer Based on Waveform
Shaping Technology
The PS-1200V accepts AC power on the input side,
processes it using internal control circuitry, and
supplies it as clean AC power on the output side.
Most of the AC energy from the input is carried
over to the output. The loss introduced by the PS-
1200V is very small, since it consists only of the
power required for waveform compensation.
Figure 1 shows a block diagram of the unit. The
signal from the secondary winding S
1 of the trans-
former reaches the adding/subtracting circuit and
appears at the output as output voltage (e
0). A part
of the output voltage is routed to the – input of the
waveform comparator for waveform comparison.
The S
2 signal from the transformer goes to the ref-
erence waveform generating circuit where it be-
comes the high-precision sine waveform (e
i) syn-
chronized to the input frequency of 50/60 Hz. This
sine wave sig-
nal is then
routed to the +
input of the
waveform com-
parator to be
used as a refer-
ence signal. By
comparing the
two input sig-
nals, a differen-
tial component
is extracted.
Based on this
information, the
adding/sub-
tracting circuit
can provide ex-
actly the re-
quired amount
of compensa-
tion for turning
the output into a
high-precision
sine waveform.
Excellent Current Capability
The power amplifier which performs waveform
compensation is configured as a pure
complementary symmetrical circuit using current
feedback for unsurpassed operational stability. The
output stage uses transistors rated for a maximum
current of 15 amperes. These devices are
connected in a 20-parallel complementary push-
pull arrangement which boasts excellent current
capability.
Frequency spectrum of power line
(photo )Frequency spectrum of PS-1200V
output (photo )
Frequency spectrum of power line
