The reliability evaluation indices of distribution system are load point average failure rate, load point average interruption duration every time, annual load point average interruption duration, annual customer interruptions, the customer interruption duration, system average interruption frequency, system average interruption duration, customer average interruption duration and average service availability index.

In this paper, a method of discriminating the working si tuation of a time frequency system composed of frequency standards and dividers on realtime basis is described and the function principle of the diseriminator is presented.

The tested is a 6kv/22kv system in testing room,in actual usage it is a 6kV/400k Wvariable frequency system device,the assay given the tested results and its analytics.

The one-line production capacity can be increased by 20% for 1.56 dtex staple fiber through using a new 2 698 f spinneret, replacing booster pump motor and frequency system, reforming carrier box of oiling roll and appropriately elevating spinning velocity.

It is shown that the kinetic energy of the quasi-two-week oscillation is larger than that of the intraseasonal oscillation, and is another important low-frequency system in the tropical atmosphere.

A multiple-frequency system of equations is averaged to obtain the relativistic equations of motion for a charged particle in the field of a quasimonochromatic wave propagating along a strong magnetic field.

The possibility of using the generalized WKB method for studying the steady states of a single-frequency system in three-dimensional potential fields which do not allow the variables to be separated in the Schr?dinger equation is considered.

Four-frequency system with a nonlinear capacitance

A helpful first step in building an adequate structural model of the present Russian economy is to build a high-frequency system based on monthly statistics for very short run projections of overall economic performance.

The equipment is aimed at manipulating five sectionalizing posts and provided with both, telecontrol and telesignaling. Time-frequency system is employed for the channel. Telesignaling from the five sectionalizing posts works continually and automatically in cyclic order. Self-checking duel information codes are adopted for each operation, in which the direct code is being compared with its inverse counterpart. The logic design is suitable for use, the circuitry is simple, and the equipment is reliable...

The equipment is aimed at manipulating five sectionalizing posts and provided with both, telecontrol and telesignaling. Time-frequency system is employed for the channel. Telesignaling from the five sectionalizing posts works continually and automatically in cyclic order. Self-checking duel information codes are adopted for each operation, in which the direct code is being compared with its inverse counterpart. The logic design is suitable for use, the circuitry is simple, and the equipment is reliable and easy in maintenance.

The standard tachometric equipment described in this paper applies a difference-frequency system for stabilizing speed and a frequency synthesizer is used as the given frequency; a scheme of linear and logical difference-frequency in parallel is provided in the controlling part and a double loop system with a silicon-controlled power supply is used in the adjusting unit. The measuring unit consists of stroboscopic measuring system, which is checked by a digital measuring device...

The standard tachometric equipment described in this paper applies a difference-frequency system for stabilizing speed and a frequency synthesizer is used as the given frequency; a scheme of linear and logical difference-frequency in parallel is provided in the controlling part and a double loop system with a silicon-controlled power supply is used in the adjusting unit. The measuring unit consists of stroboscopic measuring system, which is checked by a digital measuring device of speed. The overall accuracy of this equipment is better than±15×10~(-5)within the range from 30 to 100000 r.p.m.

The wind generating systems utilizing variable-speed constant-frequency systems can allow the rotational speed of wind turbine to vary with wind speed and operate at a constant and optimal tip speed ratio. Therefore, the wind turbines can maintain an optimal power coefficient over wide range of wind speed and the complex and expensive speed regulating mechanism can be eliminated.The field modulated generator system is a new variable-speed constant-frequency generating device. In this...

The wind generating systems utilizing variable-speed constant-frequency systems can allow the rotational speed of wind turbine to vary with wind speed and operate at a constant and optimal tip speed ratio. Therefore, the wind turbines can maintain an optimal power coefficient over wide range of wind speed and the complex and expensive speed regulating mechanism can be eliminated.The field modulated generator system is a new variable-speed constant-frequency generating device. In this system, a specially designed three phase high frequency alternator is excited by low frequency alternating current. The output, which is a modulated sine wave, is rectified, inverted and filtered to yield the constant frequency output independent of the prime-mover. This generator is specially suited for wind generating system operated in parallel with power grid. In this case, the excitation of the generator may be immediately got from the grid. The generator system synchronizes with the grid automatically. Therefore, the control and stabilization problems of the system can be greatly simplified.This paper makes a comparison between constant-speed constant-frequency and variable-speed constant-frequency wind generating systems, describes the electric circuit and the principle of operation of the field modulated generator system, presents the operational and control aspects of wind generating system utilizing this generator and experimental results of a 4 kW prototype coupled with 6m Darrieus vertical axis wind turbine in the large wind tunnel.