Research on a permanent magnet passively compensated pulsed alternator with ultra low mutual inductance research on a permanent magnet passively compensated pulsed alternator with ultra low mutual inductance
In this investigation, a permanent magnet passively compensated pulsed alternator (PMPCPA) with ultra low mutual inductance has been designed to provide an electrical pulse with the large power for the load in the shorter period. The electric excitation is replaced by the permanent magnet excitation, the passively compensated mode is adopted, and two-phase symmetrical windings with an electric angle difference of 90 degrees are respectively placed in the stator slots with both deep and shallow specifications to reduce the mutual inductance between the windings. On the basis of design scheme, the inductance of armature winding of alternator is calculated. Both noumenon and short circuit discharge models for the PMPCPA are established to perform the simulation, and the mutual inductance of PMPCPA is measured. The simulated and experimental results show that the present alternator can meet the design requirements, and the effectiveness of method for reducing the mutual inductance is verified.
Simulation research of CPA powered railgun system
The railgun, as a novel kinetic energy weapon, is being taken seriously by each country military. The pulse power source and railgun barrel, directly related to the performance of the total system, are important parts of the railgun system. The compensation pulse alternator, with its high energy storage density and power density, becomes one of the most potential pulse powers. The simulation of the pulse generator powered railgun system is researched in this paper. In order to accurately simulate the characteristic of the railgun system, the time-varying characteristic of the parameters and the kinetic resistance are taken into account in the process of building the raigun model. The railgun model is completed through the Matlab/simulink. The generator model is set up in FLUX. The coupling module between the two softwares is utilized to realize the co-simulation of the railgun system. The simulation results show that the optimum length (the displacement of the projectile exiting the muzzle while the current exactly reduces to zero) of the barrel has the relation with trigger moment of alternator. The velocity of the projectile will decrease when the trigger moment is delayed or the distance between the breech and the armature becomes further.
A technique for large-field, superficial electron therapy.
The application of electron beams to radiation therapy has received increased attention in recent years. This interest stems largely from the special characteristics of the electron depth-dose distribution; the fall-off in depth dose near the end of the range of the electrons is particularly rapid for electron beams having energies less than about 10 Mev. Such an electron beam is suitable for the treatment of widespread, superficial lesions, where it is desirable to minimize the dose to deep tissues. All the common sources of super-voltage x-rays, apart from radioactive substances, are inherently capable of producing an external beam of electrons, though with varying degrees of complexity. Electrons of about the energy suitable for superficial therapy (several Mev) may be used to produce an x-ray beam which is sufficiently penetrating for the treatment of even the deepest lesions. The Stanford medical linear accelerator was designed to provide both x-rays and electron beams. The accelerator and its applic...