11
INVERTER TECHNOLOGIES
Mitsubishi Electric inverters ensure superior performance including the optimum control of operation frequency. As a result,
optimum power is applied in all heating/cooling ranges and maximum comfort is achieved while consuming minimal energy.
Fast, comfortable operation and amazingly low running cost — That’s the Mitsubishi Electric promise.
Inverters electronically control the electrical voltage, current and frequency of electrical devices such as the compressor motor in an air conditioner.
They receive information from sensors monitoring operating conditions, and adjust the revolution speed of the compressor, which directly
regulates air conditioner output. Optimum control of operation frequency results in eliminating the consumption of excessive electricity and
providing the most comfortable room environment.
Quick & Powerful
Increasing the compressor motor speed by controlling the operation
frequency ensures powerful output at start-up, brings the room
temperature to the comfort zone faster than units not equipped with
an inverter. Hot rooms are cooled, and cold rooms are heated faster
and more efficiently.
Room Temperature Maintained
The compressor motor operating frequency and the change of room
temperature are monitored to calculate the most efficient waveform
to maintain the room temperature in the comfort zone. This elimi-
nates the large temperature swings common with non-inverter sys-
tems, and guarantees a pleasant, comfortable environment.
Vector-Wave Eco Inverter
This inverter monitors the varying compressor motor frequency and
creates the most efficient waveform for the motor speed. As the
result, operating efficiency in all speed ranges is improved, less
power is used and annual electricity cost is reduced.
Inverter size has been reduced using insert-
molding, where the circuit pattern is molded into
the synthetic resin. To ensure quiet operation,
soft PWM control is used to prevent the metallic
whine associated with conventional inverters.
Sine-wave drive soft PWM
Smooth wave pattern
MORE ADVANTAGES WITH MITSUBISHI ELECTRIC
INVERTERS – HOW THEY WORK
Impressively low operating cost is a key advantage of inverter air conditioners. We’ve combined advanced inverter technologies with cutting-edge
electronics and mechanical technologies to achieve a synergistic effect that enables improvements in heating/cooling performance efficiency.
Better performance and lower energy consumption are the result.
ECONOMIC OPERATION
KEY TECHNOLOGIES
Simple comparison of air conditioner operation control with and without inverter.
TRUE COMFORT
■
Inverter Operation Image (cooling mode)
Grooved Piping
High-performance grooved piping
is used in heat exchangers to in-
crease the heat exchange area.
DC Fan Motor
A highly efficient DC motor drives the fan of the outdoor unit.
Efficiency is much higher than an equivalent AC motor.
Joint Lap DC Motor
Mitsubishi Electric has developed a unique motor,
called the “Poki-Poki Motor” in Japan, which is
manufactured using a joint lapping technique.
This innovative motor operates based on a high-
density, high-magnetic force, leading to extremely
high efficiency and reliability.
Grooved piping
Cross-sectional view
Pipe image
Magnetic Flux Vector Sine Wave Drive
This drive device is actually a microprocessor that converts the com-
pressor motor’s electrical current waveform from a conventional wave-
form to a sine wave (180°conductance) to achieve higher efficiency by
raising the motor winding utilisation ratio and reducing energy loss.
Reluctance DC Rotary Compressor
Powerful neodymium magnets are used in the rotor of the reluc-
tance DC motor. More efficient operation is realised by strong mag-
netic and reluctance torques produced by the magnets.
DC compressor
motor ( rotor )
Neodymium
magnets
Magnetic torque
+
Reluctance torque
PAM
Conventional
inverter
Without PAM control
■
Merits of PAM Control
With PAM control
Supply
voltage
Current
Time
T
ime
PAM adjusts the form of the current wave so that it b
ecomes close to that of the supply
voltage wave. High harmonics are reduced and 9
8% of the electricity is utilized.
PAM is a technology that controls the current waveform so that it
resembles the supply voltage wave, thereby reducing loss and real-
ising more efficient use of electricity. Using PAM control, 98% of the
input power supply is used effectively.
PAM
(Pulse Amplitude Modulation)
Power increased
Efficient voltage increase
realises increased power
Significant energy savings
Remarkable reduction in power
loss saves electricity
Limited power
Insufficient power
when needed
Limited energy savings
Electricity is wasted
LEV1
Power
receiver
Heat
exchanger
Heat
exchanger
Compressor
LEV2
Power Receiver and Twin LEV Control
Mitsubishi Electric has developed a power receiver and twin linear
expansion valves (LEVs) circuit that optimise compressor perfor-
mance. This technology ensures optimum control in response to op-
erating waveform and outdoor temperature. Operating efficiency has
been enhanced by tailoring the system to the characteristics of R410A
refrigerant.
Temperature (°C)
Cooling capacity (W)
Operation time (min)
Rated capacity
Setting temperature
Indoor temperature
Measured capacity
Point 1
Point 1
When room temperature is higher than the
setting, capacity rises for the quickly adjust-
ing the temperature to the original setting.
When room temperature reaches the desired
setting, capacity eases in order to maintain
the set temperature level.
Point 2
Point 2
Highly Efficient DC Scroll Compressor
Higher efficiency has been achieved by adding a
frame compliance mechanism to the DC scroll
compressor. The mechanism allows movement
in the axial direction of the frame supporting the
cradle scroll, thereby greatly reducing leakage
and friction loss, and ensuring extremely high
efficiency at all speeds.
To fix internal parts in place, a “Heat Caulking
Fixing Method” is used, replacing the former arc
spot welding method. Distortion of internal parts
is reduced, realising higher efficiency.
Thrust gas power (minimum)
Cradle scrollFrame
Secondary back-pressure chamber
minimises thrust friction loss
Primary back-chamber minimises
leakage loss
Thrust friction loss (minimum)
Leakage loss (minimum)
Fixed scroll
Frame can
move in direction
of axis
Substantial
reduction in leakage
and friction loss
Our Rotary Compressor
Our rotary compressors use our original “Poki-Poki Motor” and
“Heat Caulking Fixing Method” to realise downsizing and higher
efficiency, and are designed to match various usage scenes in
residential to commercial applications. Additionally, development of
an innovative production method known as “Divisible Middle Plate”
realises further size/weight reductions and increased capacity while
also answering energy-efficiency needs.
Our Scroll Compressor
Our scroll compressors are equipped with an advanced frame
compliance mechanism that allows self-adjustment of the position
of the orbiting scroll according to pressure load and the accuracy of
the fixed scroll position. This minimises gas leakage in the scroll
compression chamber, maintains cooling capacity and reduces
power loss.
Heat Caulking Fixing Method
Heat Caulking
Fixing Method