|
"Other Related
Patents for EET
Technology"
| 4,190,793 |
Energy
Economizer for Induction Motors:
A standard, unmodified AC induction motor has its stator
winding energized from a sine wave power source through a signal-responsive wave
modifier operative to control the portion of each cycle of the swine
wave which is coupled from said source
to the stator winding. Load detecting means, comprising a
comparatively small AC generator coupled to the rotor of
the motor, produces a control signal, varying with variations in
the load on the motor, for controlling the wave modifier
to increase the field density of the stator winding with
increases in load on the motor, and to decrease
the field density of the stator winding with
decreases in said load. |
  |
| 4,242,625 |
Energy
Economizer for Poly-phase induction motors: A standard three
phase induction motor starts with all three of its input
connections connected to the three phase power line. Two of these connections
are through triacs which remain continously conducting below said motor's particular most
energy-efficient speed, which is above about
95% of synchronous speed. This assures full starting torque and undiminished overload
handling capability. The triacs, in response to a control signal,
may open the circuits over a sufficiently wide portion of the
sine wave input voltage to substantially maintain said particular
efficient speed under all rated load conditions. To assure smooth operation and
maximum energy savings, the two triacs conduct differently at very light motor
loads. The DC control voltage which determines the operation of the triacs
is generated by a frequency discriminator circuit which receives
its information from a load detecting device that is frequency modulated
by load/speed related properties inherent to induction motors. |
|
| 4,297,628 |
Energy
Economizer for Induction Motors: A standard,
unmodified AC induction motor has its stator winding energized from
a sine wave source through a signal-responsive wave modifier
operative to control the portion of each cycle of the sine wave
which is coupled from said source to the stator winding. A motor current
demodulator, responsive to efficiency-related parameters of the inrush current to
the stator winding each time the current in the stator winding increases
from zero, produces a control signal for the wave modifier, which signal
varies with a decrease in motor operating
efficiency below the maximum inherent efficiency of the motor
to increase the field density of the stator winding
in response to increases in motor load and to decrease
said stator field density in response to decreases in said
load and/or to maintain the most energy-efficient stator field density
at rated motor loads when the voltage magnitude of
the sine wave source increases or decreases from
its nominally rated magnitude. |
|
| 4,382,223 |
Voltage and
Frequency-controlled AC Wave modifier:
A standard, unmodified AC induction motor has its stator
winding energized from a sine wave power source through a signal-responsive wave
modifier operative to control the portion of each cycle of the sine
wave which is coupled from said source
to the stator winding. Load detecting means, comprising a
comparatively small AC generator coupled to the rotor of
the motor, produces a control signal, varying with variations in
the load on the motor, for controlling the wave modifier
to increase the field density of the stator winding with
increases in load on the motor, and to decrease
the field density of the stator winding with
decreases in said load. |
|
| 4,414,499 |
Motor
Protecting Improved Energy Economizer for Induction
Motors:A standard, unmodified AC
induction motor has its stator winding energized from a sine
wave source through a signal-responsive wave modifier operative to control
the portion of each cycle of the sine wave
which is coupled from said source to the stator
winding. An improved motor current demodulator, responsive to efficiency-related parameters
and excessive stator winding inrush current each
time said current increases from zero, produces signals
for controlling the wave modifier, thereby to maintain optimum
motor efficiency with varying motor loads and power
source variations, and the signals also control a motor protector circuit which
inhibits said wave modifier thereby to deenergize said stator winding under
excessive input current conditions, excessive motor temperature or a
potentially damaging combination thereof. |
|
| 4,636,702 |
Energy
Economizer Controlled-Current Start and Protection for Induction
Motors: A standard, unmodified induction motor
starts with reduced input current, energy consumption and mechanical
stress and is further protected from AC power source "phase loss",
excessively low or high voltage or a locked-rotor condition during
start-up or any subsequent moment while running when its stator
winding is energized from a sine wave source through a
signal-responsive wave modifier operative to control the portion of
each cycle of the sine wave which is coupled from said source to the
stator winding. A stator current sampling arrangement, and a motor current demodulator responsive to the first few hundred
microseconds of stator winding initial inrush current each time said
current increases from zero cooperate under certain conditions to produce signals for
an associated wave modifier, thereby to achieve a preferred magnitude of motor
starting current under rated load conditions and
achieve near-optimum motor operating efficiency during start-up and subsequent
running with reduced loads and associated motor protection circuits
which inhibit said wave modifier thereby to de-energize said stator
winding under locked-rotor conditions that occur when motor start-up is
attempted or later when the motor is running, or an
AC power source anomaly occurs which would otherwise cause
start-up stalling, excessive motor running current or motor
stalling under rated loads. |
|
| 4,910,450 |
Low Cost Three
Phase Energy Economizer: An energy economizing AC
power control system for energizing the stator windings of a three
phase induction motor comprises an AC generator connected to the
motor rotor shaft for generating an AC signal that is frequency
modulated in response to load induced speed variations of the rotor,
a variable resistance whose magnitude is responsive to the frequency modulated signal, an AC
power proportioning switch which produces a single phase output consisting
of pulses whose widths vary with variations in the magnitude of the
variable resistance, a single phase-to-three phase converter coupled to the output of
the proportioning switch for producing three control
signals that occur respectively at the frequency of and
during each voltage phase alternation of a three phase
sine wave power supply, and three solid state switches that
are respectively controlled by said control signals for controlling the
time duration that each alternation of the three phase power
supply is coupled via an associated one of the
solid state switches to an associated one of
the motor stator windings. |
|
does not include the other 40 or so
International Patents... |
Technical