| 摘要 |
The invention relates to a current sensor operating in accordance with the principle of compensation, comprising
- a primary winding through which the current to be measured flows, creating a magnetic field,
- a secondary winding, through which a compensation current flows, which generates a magnetic field compensating the primary winding,
- a magnetic core ...
- a terminating resistor connected in series to the secondary winding,
- sensor means, which are exposed to the resulting magnetic field of the primary and secondary windings,
- a booster circuit connected downstream of the sensor means which feeds the compensation current to the secondary winding via the terminating resistor, whereby the booster circuit comprises a switched mode amplifier with a pulse width and density modulator that operates based on pulse width and density modulation, turning the compensation current into a pulse width and density modulated current, with a switching frequency that is a function of the compensation current in the sense that the switching frequency is high at small currents and low at high currents. |
