Modulation method for bridge circuits for the particular control of direct current motors

A control system for modulating the supply voltage of a load fed by a bridge circuit, wherein the load is switched as a function of a predetermined setpoint value for the input current isoll by means of power electronics to an intermediate circuit voltage UDC, characterized by

• a pulse generator (9) to put out pulses having the period T,
• an integrator (6) for the integration of the intermediate circuit current iDC over the period T, wherein the integrator is reset by the pulses of the pulse generator,
• a comparator (7) to compare the integrated value with a predetermined setpoint value T·Isoll, wherein the comparator sends out a signal when the setpoint value is exceeded,
• a bistable trigger circuit (10) that is switched to a first state by the pulses of the pulse generator and is switched to a second state by the signal of the comparator.

A control system for modulating the supply voltage of a load (1) fed by a bridge circuit, wherein the load is switched as a function of a predetermined setpoint value for the input power P1soll by means of power electronics (2) to an intermediate circuit voltage UDC, characterized by

• a pulse generator (9) to put out pulses having the period T,
• an integrator (6) for the integration of the input power P1=uDCiDC over the period T,
• wherein the integrator is reset by the pulses of the pulse generator,
• a comparator (7) to compare the integrated value with a predetermined setpoint value T·P1soll, wherein the comparator sends out a signal when the setpoint value is exceeded,
• a bistable trigger circuit (10), that is switched to a first state by the pulses of the pulse generator and is switched to a second state by the signal of the comparator.