| 摘要 |
The active smoothing device has the advantage of being able to operate with capacitors of relatively low capacitance compared to an equivalent three-pole filter circuit with a series impedance and a capacitor connected in parallel. For this purpose, a field effect transistor (FET) is present, the anode-cathode section of which forms the series impedance, and the control terminal of which is connected to a reference terminal (B') via a circuit consisting of the collector-emitter section of a transistor (T) and a limiting resistor (R6), which are connected in series. Also, the output signal of an operational amplifier (OP) is applied to the base of the transistor (T). The non-inverting input of the operational amplifier (OP) is connected both via a capacitor (C1) to the third pole (B) of the three-pole network, and via a first resistor (R1) to a regulating potential terminal (Q), which is connected on the one hand via a first bridge resistor (R2, R3) to the input (E) of the three-pole network, and on the other hand via a second bridge resistor (R8) to the reference potential (B'). The inverting input of the operational amplifier (OP) is connected on the one hand via a reference voltage source (Ub, R10) to the output (A) of the three-pole network, and on the other hand via another bridge resistor (R9) to the reference potential (B'). Also, a control resistor (R5) is inserted between the input (E) of the three-pole network and the control input of the field effect transistor (FET). <IMAGE> |
