Electronic Speed Controller Research Articles

Noise pollution in the city of Curitiba, Brazil

A study carried out in 2000 in the city of Curitiba, Brazil, showed that the noise levels generated by the traffic have decreased when compared to the levels obtained in a similar survey conducted in 1992. Noise levels were measured in 350 points spread through the city considering the same criterium adopted in 1992. A study conducted by Maschkle showed that levels higher than 65 dB(A) are likely to cause health disturbances. The current survey showed that 80.6% out of the measured points presented noise levels over 65 dB(A), whereas in the previous survey 93.4% out of the measured points presented levels over that value. In spite of this, the 2000 levels are still too high considering the local legislation, putting the city in a high risk category to health impairments. Among the possible reasons that caused such a reduction on the noise levels some can be cited: better conditions of the new road vehicles circulating in the Brazilian cities and in Curitiba as well, installation of electronic speed controllers, and the establishment of speed limits for some urban streets and avenues.

Towards A Non-competitive Motoring System:Unexplored Opportunities For Social, Cultural,Ecological And Economic Progress

The paper explores the use of standardized and limited speeds and acceleration with steady traffic flow without overtaking and competing. This approach could be a condition for substantially reducing traffic damage and saving traffic expense. Enforced by law and by compulsory built-in electronic speed controllers, non-competitive traffic would provide new possibilities instead of speed restrictions. Theoretical and empirical studies indicate benefits for social, cultural, economic and environmental conditions.

98/03853 Prediction of internal temperature in three-phase induction motors with electronic speed control

98/03853 Prediction of internal temperature in three-phase induction motors with electronic speed control

Prediction of internal temperature in three-phase induction motors with electronic speed control

Internal temperatures of induction motors with electronic control are not only affected by the harmonic components of the electronic source but also by the reduction of the cooling capacity as the motor speed drops. This paper develops a model able to determine the internal temperatures in a squirrel-cage three-phase induction motor fed by an inverter. The temperatures are calculated in a 20-node-thermal network whose parameters depend on the voltage wave supplied by the source and the motor speed. Through this model, it is possible to determine the temperatures in the tested motor and to analyze the influence of the fundamental frequency voltage on steady state temperatures and motor performance limitation, specifically the maximum acceptable load, so that the motor does not exceed its normal steady state temperature when is supplied by an inverter.

Design of an Electronic Speed Controller for a Gasoline Engine. 2nd Report, Improvement of Follow-Up Control using Two Degree of Freedom Control.

We present an application of two degree of freedom control combined with H-infinity control to an electronic speed controller for a gasoline engine. The electronic speed controller is used for speed control of the gasoline engine of a forklift truck. This system needs a function of engine speed follow-up to the reference speed set with open rate of the accelerator pedal. It also needs a function of constant engine speed against torque disturbance, that is the load of a hydraulic pump during loading operation. The results of both simulations and experiments show that two degree of freedom control combined with H-infinity control enables excellent in the capabilities of follow up control, torque disturbance control and robust stability.

Design of an Electronic Speed Controller for a Gasoline Engine. 1st Report. Torque Disturbance Control Using H-infinity Control.

Design of an Electronic Speed Controller for a Gasoline Engine. 1st Report. Torque Disturbance Control Using H-infinity Control.

Fuzzy Auto-Tuning for a Gasoline Engine's Electronic Speed Controller.

PID (Proportional, Integral and Derivative) control is generally used in industrial products today, because of its simple algorithm and good adaptability on the scene. However, the matching of PID control parameters is difficult, thus we are looking forward to the development of auto-tuning of PID control parameters. In this study, we attempted fuzzy auto-tuning for a gasoline engine's electronic speed controller with PID control. Here fuzzy production rules are independently applied, and each rule is weighted by the degree of inputs of assumed parts. This fuzzy reasoning method is useful in simplifying the description of fuzzy production rules and provides a simple means of control similar to that performed by humans.

A New Speed Controller for Induction Motors Driving Agricultural Fans

Traditional electronic speed controllers for agricultural fans consist of analogue circuitry which senses room temperature and adjusts the motor voltage, and consequently its speed, to vary the fan airflow. Fan controllability is compromised by inherent nonlinearity of fan airflow as related to temperature. This paper describes the design and testing of an electronic speed controller which solves this problem by linearizing fan airflow versus temperature. The controller circuitry uses an erasable programmable read-only memory (EPROM) chip. The input to the EPROM is an analogue representation of temperature converted to digital form. The digital contents then are converted to an analogue signal that fires a triac and consequently controls the voltage input to the fan motor. A linearized control characteristic, i.e., temperature versus airflow rate, can be obtained by storing appropriate voltage values in the EPROM. These values correspond linearly to the desired fan speeds.The paper documents the testing of the electronic speed controller (ESC) for agricultural ventilation fans. The controller was developed and tested with three commecially available fan systems. Linearized temperature versus airflow rate characteristics were obtained. The improved linearity of this controller at a minimal cost (less than £25 in parts) solves a major problem experienced with variable speed ventilation fans.

Skeptics and Visionaries Examine Energy Saving

Amory Lovins of Rocky Mountain Institute in Snowmans, Colorado reported at the Dahlen workshop on 'Limiting the Greenhouse Effect: Options for Controlling Atmospheric CO{sub 2} Accumulation' that his institute has identified 50 energy-saving technologies that, if implemented worldwide, would cut global energy use in half. In the three sectors of energy use, lighting, motors, and appliances, the possibility of saving two-thirds of the total U.S. demand for electricity exists now according to Lovins. Compact fluorescent tubes could save 10% electricity, new electronic speed control systems, new materials and designs, new drive trains, and new bearings for electric motors could save nearly 60% of the electricity used by motors, and better insulation could make refrigerators (the most energy consumptive appliance except space and water heaters) as much as 90% more efficient. Price seems to be the overall barrier to realizing these energy savings. Some incentives for energy savings are being offered by utilities, and with massive energy efficiency, the global warming might be mitigated.

Electronic speed control for the analytical ultracentrifuge

An electronic speed control for the Spinco model E analytical ultracentrifuge is described. An accuracy of better than 1:104 is obtained, using digital circuits and a crystal-controlled reference oscillator. Acceleration is automatic and the circuitry is provided with several safety devices.

Low-cost electronic speed controller for induction motors

There are three basic methods available for the speed control of induction motors. One of these—the variation of the supply frequency—is probably the most versatile method. It permits continuous variation of speed while maintaining a constant slip for all rotor speeds

New Pin-Registered High-Speed 16mm Motion-Picture Camera

The development of the Locam series of intermittent pin-registered cameras has included a patented crank used in the intermittent mechanism which has proven superior to geared designs, especially during high-speed operation, for eliminating backlash and induced vibration. Module construction provides for interchange- ability of major components, greater reliability and easier maintenance. The shutter is conventional but operates at a half-revolution per frame, making possible an equivalent opening of 180°, which was not before available in cameras of this type. A solid-state electronic speed control offers infinitely variable frame-rate selection over the entire range and regulates film speed to within 1% at 400 frames s. Film shot at this speed was projected to show picture quality and extreme steadiness.

Automatic platelet counting with the Couler particle counter.

A method for accurately counting platelets is described using the Coulter counter model B fitted with a standard 100mu aperture tube. This enables the counter to be used for red and white cell as well as platelet counts using the same aperture tube. The method uses standard equipment except for a small inexpensive electronic speed controller.

Automatic Acceleration and Speed Control for an Analytic Ultracentrifuge

A complete profile of automatic acceleration for an analytic ultracentrifuge is established with an electronic speed control system. Motor current is controlled by a Sola (resonant transformer) resonant current source during acceleration and when the rotor reaches full speed the Sola saturates, forming a constant voltage regulator. As full speed is approached, a closed loop system is introduced which compares the frequency of a magnetic-geartooth counter to a reference circuit and then applies the error as voltage increments to the drive motor. To evaluate performance, a computer program was developed to compare manual control with the automated system. Results indicate greater accuracy in the automated system for the integrated ω2dt during the acceleration phase of ultracentrifuge operation, and extremely stable and accurate control of final speed (to within 10 ppm or less).

Speed control of large wind tunnels

The paper describes an electronic speed control which has been installed for the composite drive of the 8 ft high-speed wind tunnel at the Royal Aircraft Establishment, Bedford. A description of the requirements of a wind-tunnel speed control is given, and several methods of control are discussed. The selected control system, which is discussed in detail, although of the conventional closed-loop technique, has special problems when gas-turbine prime movers power part of the composite drive. A full description of these special features is given, together with a mathematical analysis of the closed-loop system.

An electronic speed control for the towing carriage of a ship-model testing tank

An electronic speed control for the towing carriage of a ship-model testing tank

An electronic speed control for the towing carriage of a ship-model testing tank

The paper describes an electronic speed control which has been fitted to one of the two ship-model testing tanks at the National Physical Laboratory. A description of certain aspects of ship-model testing is included in a discussion of the reasons for fitting electronic control and of the performance required of such a control. The control system is a particular application of closed-loop automaticcontrol technique. A general description of it includes full details of those features which are special to this particular application, and a mathematical analysis of the design. Some typical test results obtained are shown in the form of graphical records and Tables.

Electronic speed control of motors

IN THE EARLY years of the electrical industry there was no acceptable a-c motor. After the development of the induction motor and the synchronous motor two machines were available which are unsurpassed in simplicity, reliability, and economy. These motors are, however, both inherently constant speed machines. In later years, a variety of a-c motors have been developed and a number of these have had adjustable or variable speed characteristics. There is, however, as yet, no adjustable-speed a-c motor so flexible as the Ward-Leonard combination, and there is still room for much improvement in adjustable speed a-c motors.