Motors applications

Smeaton, R.W.. Motor Application and Maintenance Hand Book, McGraw Hill, New York (1969). 

Single phase motors do exhibit operational problems in pony motor applications. The capacitors in these motors store energy and the motors resist external attempts to rotate them. Single phase motors can be made to work on pony motor applications by splicing into the capacitor circuit and connecting it in series with an open auxiliary switch in the active motor starter. 

Most induction ac motors are fixed-speed. However, a large number of motor applications would benefit if the motor speed could be adjusted to match process requirements. Motor speed controls are the devices which, when properly applied, can tap most of the potential energy savings in motor systems. Motor speed controls are particularly attractive in applications where there is variable fluid flow. In many centrifugal pump, fan, and compressor applications mechanical power grows roughly with the cube of the fluid flow. To move 80 percent of the nominal flow only half of the power is required. Centrifugal loads are therefore excellent candidates for motor speed control. Other loads that may benefit from the use of motor speed controls include conveyers, traction drives, winders, machine tools and robotics. 

The factors presented in the preceding paragraphs must be evaluated in the light of a given motor application. In general, they may be summarized for a general-purpose application. Also see references 47, 57, and 87. 

The following listing of data to be supplied to manufacturers when ordering motors or requesting bids is based on the requirements and recommendations of a number of representative manufacturers. This list is split into vital and desirable information and is intended as a checklist in preparing both requisitions and purchase orders. By using this list, you will give the manufacturer a clear picture of your needs for most motor applications in the oil and petrochemical industries and eliminate call-backs, requests for supplementary information, and so on. 

In general, the typical electric motor applications in the oil and gas industry arc polyphase motors (either squirrel-cage or wound-rotor motors). 

Motor applications of PVC plastisol propellants have been notably free of unstable burning problems. 

A knowledge and understanding on the nature of the helix switching may be helpful in designing PM-transition capability and characteristics in diverse screw-sense inversion related applications, such as chiroptical switches and memory, switchable chiral separation columns, molecular recognition and molecular motor applications. 

New prepolymers based on 3,3-bis (azidomethyl) oxetane (BAMO) and 3-nitratomethyl- 3-methy-loxetane (NMMO) are used in advanced pintle-controllable solid rocket motor applications. These polymers yield favorable propellant energy with the combination of nitrato esters and ammonium nitrate, and allow solid propellant designs to compete with liquid propellants in arenas of energy management, approaching true start-stop-restart operation. 

The kinetics of formation of this zirconium diboride platelet reinforced zirconium carbide have been discussed, as have possible formation mechanisms [36] and detailed microstructural and orientation relationships between the phases [37]. These materials, in addition to being very refractory, are quite hard. Potential applications typically involve wear resistance, either at low to moderate temperatures or for short times at very high temperatures, such as in biomedical and rocket nozzle or rocket motor application [35]. 

Application of Types of Motors and Typical Costs. A classification of types of motors applicable to specific processing equipment has been prepared by Kropf in Fig. 4-5 with costs of motors given in Table 6-2 and Fig. 6-22. 

Willner, I. (2005). Nanoparticle- and nanorod-biomaterial hybrid systems for sensor, circuitry and motor applications. Contrib Sci 3, 79-90. 

In the case of constantly fluxed synchronous motors, the stator cmrent will follow the motor torque more closely. After adding excitation losses, the synchronous motor efficiency is still shghtly better than the induction motor. The drive inverter for a synchronous motor supplies the armature or torque producing current, compared to the induction motor apph-cation where the inverter must supply torque producing current and magnetising current In the synchronous motor application, the motor operates at unity power factor, which reduces current demand in the inverter section. As a result, there are fewer losses in the inverter and motor, and to a lesser extent fewer losses in the converter. 

The advantage of reduced RMS kVA at the converter also applies to synchronous motor application. Listed below are the data and results for a similar synchronous motor application ... 

Drive Power Demand Induction Motor Application Synchronous Motor Application 12 Pulse Parallel DC Drive... 

For the induction motor in the application in Table 1, the motor specified has a 9% margin (i.e., is 91% loaded on RMS). A similar 9% margin applied to the drive transformer for the AC drive application would require a drive transformer rated 2,675 kVA for the 3,000 kW induction motor application. This result has sometimes lead to questions by the client who is concerned with a drive supply transformer rated at a lower power than the hoist motor it is supplying. The results also demonstrate the benefits of Voltage source IGBT drives over DC drives in reducing the kVA demand on mine hoist applications. 

These materials are used for high-performance electrical and electronic parts, under-the-bonnet motor applications, etc. 

Electrical motor applications, wire, cable, transformer and high-voltage distribution equipment, hermetic applications with refrigerator and air conditioner motor (22)... 

Motors are familiar to all operations personnel, and most will have had a great deal of experience with motors. Each motor application is different, however, and requires a specific review. This is especially important when making changes in operation or when installing stock motors. 

Electric-motor application for the plant engineer is the common-sense matching of load requirements with motor characteristics. Motor types, styles, sizes, mountings, and enclosures vary greatly. So the first step in using electric motors correctly is to understand them and the terminology the motor industry uses to describe them. 

Motor application begins by matching load requirements with motor characteristics. A correctly applied motor must be able to start the load, bring it up to operating speed, and run as long as necessary through all expected variations in the load. 

Some Basic Differences. The primary difference between lEC and traditional NEMA starters is one of concept. A 10-hp (7.5-kW) NEMA starter can be used in virtually any 10-hp (7.5-kW) motor application. This is not the case for lEC control, which must be derated for difficult applications. 

Operating requirements for specific motor applications must also be considered and generally include constant, variable, adjustable, and multispeed operation. 

Figure 63 Schematic of a pressurised oven curing rig used in rocket motor applications.

Applications for non-reserve batteries include fire and burglar alarm systems, barricade lights, lantern and flasher applications, small d.c. motor applications, such as tape recorders, toys, etc., light packs for emergency slide crates in commercial aircraft, and emergency location transmitters on aircraft. 

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