ToshibaTEC: Press Release

Toshiba TEC Corporation (TTEC) now has technology with which we can build a new structural motor driven by a new method (pet name: Jet Motor). Using this technology, we also developed a motor-integrated pump (pet name: Jet Pump).

The Jet Pump opened up a new technological field, combining our unique motor technology and the new pump technology. TTEC has already applied for a patent for this new technology, in many countries.

For many years, TTEC has been developing, manufacturing, and marketing the motors used for vacuum cleaners and small precision motors and has the expertise in motor technology. As we are more aware of environmental problems, the market needs are moving to a motor which is environmentally friendly, highly-efficient (energy-saving), small (resource-saving), top-performing, and controllable.

To meet these market needs, TTEC conducted research and development to design a new structural motor with a new concept and succeeded in establishing the Jet-Motor technology.

Using the new technology such as a salient-pole rotor with permanent magnets, windings fixedly wound around the neighbor poles of different polarity, optimal torque control in the wide range, TTEC designed a highly-efficient, small, and light motor which can be driven by a brute supply. (For descriptions, see Pages 3 to 4.)

TTEC also designed the Jet Pump, a small and light motor-integrated pump, using the Jet-Motor technology and an impeller-structural rotor. (For a description, see Page 5.) As the Jet Motor rotates both in the forward and reverse directions, you can use the Jet Pump for both supplying and discharging purposes.

Applications for liquid:

1. Submersible pumps
2. Fuel pumps
3. Feedwater systems for high-rise buildings
4. Sump pumps
5. Swimming aids (motor-assisted swimming boards)

Changing the impeller structure will enable you to use the Jet Pump for both supplying and exhausting air.

Applications for gas:

1. Vacuum cleaners
2. Air pumps

In addition to the above, extensive applications can be expected.
The Jet Motor and Jet Pump will be commercially manufactured in 2001.

1. Jet-Motor Technology

The motor technology which TTEC has established made new structure and new driving method possible. The main features are as follows:

(1) New Structure

1) The two windings are wound around each pole so that the neighbor poles of each phase can be magnetized to a different polarity (conventionally, one winding was used). Electrical current flows in each winding in the same direction so that the two neighbor poles can be magnetized to a different polarity (conventionally, electrical current flowed in the winding in both directions).

2) The rotor has salient poles and uses permanent magnets to generate magnetic poles.

3) Windings from the diagonally positioned magnetic poles, in which electrical current flows in the same direction, are connected. (This is done for three pairs.) Then, each connected winding is connected in parallel with the winding from the neighbor pole, in which electrical current flows in the opposite direction. As a conclusion, there are three connected windings. One side of each connected winding is coupled and connected to the power supply. The other side is to the driving transistors respectively.

4) With this new structure, an excitable range of the Jet Motor has been extended to 60 degrees while that of the conventional switched reluctance motors is 30 degrees (which means that the rotatable range is 30 degrees). Thus, motor efficiency and motor controllability have been improved.

(2) New Driving Method

This method uses a microcontroller, position sensor, and driving circuit.

1) Control Circuit

- The target speed can be achieved in a short period of time by receiving a signal from the position sensor and controlling the time to start and stop exciting each phase with the microcontroller.

- Optimal control is carried out to achieve the target speed at the smallest current by updating the optimal time to start and stop exciting each phase using a learning mechanism of the microcontroller.

- Force is controlled by controlling the pulse width. High force requires a long exciting time and low force, a short exciting time.

2) With a new winding method, only three driving transistors are required while the conventional method required six; reduced by half.

3) Besides the very wide exciting range, the motor operates efficiently at the highest force and can be driven by a brute supply using a learning mechanism. Also, it operates efficiently because unnecessary magnetic fluxes disappear.

2. JetPump

Using the Jet-Motor technology, TTEC developed a motor-integrated pump.

(1) Structure
The Jet Pump is an axial-flow pump with the Jet Motor. The impeller is used in the rotor of the Jet Motor except for the salient-pole areas.