Abstract: A mass transit vehicle traction motor control system includes an automatic control block for receiving and processing a tachometer signal having a first resonance signal superimposed thereon to produce a rate request signal having a corresponding second resonance signal superimposed thereon. A filter is provided for decreasing an amplitude of the second resonance signal whereupon the rate request signal is isolated therefrom. A communication and control block and a propulsion and control block co-act to process the isolated rate request signal to produce a speed control signal that is configured to cause a traction motor of a mass transit vehicle to provide motive force to the mass transit vehicle at a rate related to the value of the speed control signal.

Abstract: A device for detecting the unbalance .DELTA.i between the two fractions of the return traction current flowing in the two rails of a railroad track, in the presence of a signalling current in the respective track circuit, includes a linear combination circuit (3) that receives two signals (i.sub.1 and i.sub.2) which are proportional to the two currents actually present in the two rails and obtains both the difference (i.sub.1 -i.sub.2) and the sum (i.sub.1 +i.sub.2) thereof. A demodulating circuit (4), fed with the difference signal, takes from it the modulating signal of the signalling current and feeds it to a sample generator circuit (5), which generates a sample function M(t). The sample function is supplied to two successive sampling circuits (106 and 206), one of which also receives the difference signal and produces a sampled difference signal M(i.sub.1 -i.sub.2), while the other also receives the sum signal and produces a sampled sum signal M(i.sub.1 +i.sub.2).

Abstract: Control apparatus for determining the power regenerating operation of a train vehicle is disclosed in relation to the provision of a control signal in conjunction with the operation of the power supply rail of the train vehicle track, such that power regenerating operation of the train vehicle is prevented unless such operation is desired as indicated by the presence of that control signal.