Patent · US Expired

Power regulator with overcurrent protection

US4855858A · kind A · utility

19Cited by
25References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 29, 1987
Grant dateAug 8, 1989
Priority date
Expiry dateDec 29, 2007

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02M3/3378
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A regulator includes a switching transformer (TR) whose primary winding is divided into two halves through which current flows alternatingly via one respective switching transistor (Q1, Q2). The pulses on the secondary side of the transformer are rectified to attain the output voltage. The output voltage is controlled by pulse width modulated driver pulses for the two switching transistors. A protective circuit (12) with immediate effect terminates the currently applied driver pulse when the current flowing through the conductive switching transistor reaches a critical current value. A protective circuit (14) with delay effect prevents the generation of further driver pulses upon a further increased overload, this prevention being limited with respect to time. The protective system directly is controlled by the primary current of the power regulator.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.