Static high voltage switch usable in a switchable high voltage D.C. generator

Claim 2

A static high voltage switch for controllably coupling and decoupling a high voltage D.C. source to and from a load, comprising: a bridge of n series-connected, electrically controllable switch circuits, each switch circuit including at least one semiconductor switching element and having a current input, a current output and a control port including a control input and a contol return, the current output of a switch circuit being connected to the current input of the adjacent switch circuit of the bridge to form the series connection of switch circuits, the current input of the first switch circuit of the bridge and the current output of the last switch circuit of the bridge comprising terminal ends of the bridge for connection to the high voltage D.C. source and load, respectively; a plurality of n-toroidal cores, one core being associated with each of the switch circuits, each core being wound with a secondary winding including first and second ends and an intermediate tap; a plurality n of circuit means, one circuit means being associated with each toroidal core and its corresponding switch circuit for coupling the secondary winding of its associated toroidal core to the control port of its associated switch element, each circuit means including a first diode and series resistor coupling the first end of its associated secondary winding to the control input of its associated switch circuit, a second diode coupling the second end of the associated secondary winding to the control input, means for coupling the control return to the intermediate tap of the secondary, and a capacitor coupling the control input to the control return; and a primary winding formed by an insulated wire element passing through each of the n-toroidal cores for coupling to an external control signal source for controlling the static high voltage switch.

Claim 3

A switch according to claim 1, wherein (a) the toroidal cores are stacked so as to have a common axis, (b) the wire element forming the primary winding comprises a high voltage cable element, and (c) the switch is constructed in modules, each module including one of the toroidal cores with its secondary winding, its associated switch circuit and its associated circuit means coupling the secondary winding to the switch circuit.

Claim 4

A switch according to claim 1 or 2, wherein (a) the switch element comprises a thyristor having a gate forming the control input and an avalanch diode in parallel with the thyristor, and (b) the primary winding is coupled to a D.C. power source through a primary switch controlled by periodic pulses from the external control signal source.

Claim 5

A switch according to claim 1 or 2, further including primary winding circuit means comprising: a first primary switching element for coupling a first end of the primary winding to a D.C. power source, the switching element being adapted to receive a pulse signal from the control signal source; and means for coupling a second end of the primary winding to the D.C. power source.

Claim 6

A switch according to claim 4, wherein the primary winding circuit means further comprises a second primary switching element coupled in circuit with the primary winding and being adapted to receive a binary digital control signal from the control signal source for controlling the starting and stopping of the static high voltage switch.

Claim 7

A switch according to claim 1 or 2, further including an output diode bridge for coupling the terminal ends of the bridge of n series-connected switch circuits to the high voltage D.C. source and load, the terminal ends of the series connected switch circuits being coupled to a first diagonal of the output bridge, the second diagonal of the output bridge, being connected to the high voltage D.C. source and load whereby the high voltage static switch can be operated bidirectionally.

Claim 8

A static high voltage switch for controllably coupling and decoupling a high voltage D.C. source to and from a load, comprising: a first bridge of n1 series-connected electrically controllable switch circuits each switch circuit including at least one semiconductor switching element and having a current input, a current output and a control port including a control input and a control return, the current output of a switch circuit being connected to the current input of the adjacent switch circuit of the bridge to form the series connection of switch circuits, the current input of the first switch circuit of the bridge and the current output of the last switch circuit of the bridge comprising terminal ends of the bridge; a second bridge of n2 series connected electrically controllable switch circuits each switch circuit including at least one semiconductor switching element and having a current input, a current output and a control port including a control input and a control return, the current output of a switch circuit being connected to the current input of the adjacent switch circuit of the bridge to form the series connection of switch circuits, the current input of the first switch circuit of the bridge and the current output of the last switch circuit of the bridge comprising terminal ends of the bridge; a first plurality of n1-toroidal cores, one core being associated with each of the switch circuits of said first bridge, each core being wound with a secondary winding including first and second ends and an intermediate tap; a second plurality of n2-toroidal cores, one core being associated with each of the switch circuits of said second bridge, each core being wound with a secondary winding including first and second ends and an intermediate tap; a first plurality n1 of circuit means, one circuit means being associated with each toroidal core of the first plurality n1 of toroidal cores and its corresponding switch element for coupling the secondary winding of its associated toroidal core to the control port of its associated switch element, each circuit means including a first diode and series resistor coupling the first end of a secondary to the control input of its associated switch circuit, a second diode coupling the second end of the secondary to the control input, means for coupling the control return to the intermediate tap of the secondary, and a capacitor coupling the control input to the return; a second plurality n2 of circuit means, one circuit means being associated with each toroidal core of the second plurality n2, of toroidal cores and its corresponding switch element for coupling the secondary winding of its associated toroidal core to the control port of its associated switch element, each circuit means including a first diode and series resistor coupling the first end of a secondary to the control input of its associated switch circuit, a second diode coupling the second end of the secondary to the control input, means for coupling the control return to the intermediate tap of the secondary, and a capacitor coupling the control input to the return; a primary winding formed by an insulated wire element passing through all of the n toroidal cores (n=n1+n2) for coupling to an external control signal source for controlling the static high voltage switch; a pair of terminals for connection to the high voltage D.C. source and load, respectively; and first and second diode circuit means for coupling the terminals to the terminal ends of the first and second bridges, the diodes coupling the terminals to the two bridges being arranged in opposite polarity so that bidirectional operation of the static high voltage switch is made possible.

Claim 9

A static high voltage switch for controllably coupling and decoupling a high voltage D.C. source to and from a load, comprising: a first bridge of n1 series-connected electrically controllable switch circuits each switch circuit including at least one semiconductor switching element and having a current input, a current output and a control port including a control input and a control return, the current output of a switch circuit being connected to the current input of the adjacent switch circuit of the bridge to form the series connection of switch circuits, the current input of the first switch circuit of the bridge and the current output of the last switch circuit of the bridge comprising terminal ends of the bridge; a second bridge of n2 series connected electrically controllable switch circuits each switch circuit including at least one semiconductor switching element and having a current input, a current output and a control port including a control input and a control return, the current output of a switch circuit being connected to the current input of the adjacent switch circuit of the bridge to form the series connection of switch circuits, the current input of the first switch circuit of the bridge and the current output of the last switch circuit of the bridge comprising terminal ends of the bridge; a first plurality of n1-toroidal cores, one core being associated with each of the switch circuits of said first bridge, each core being wound with a secondary winding including first and second ends and an intermediate tap; a second plurality of n2-toroidal cores, one core being associated with each of the switch circuits of said second bridge, each core being wound with a secondary winding including first and second ends and an intermediate tap; a first plurality n1 of circuit means, one circuit means being associated with each toroidal core of the first plurality n1 of toroidal cores and its corresponding switch element for coupling the secondary winding of its associated toroidal core to the control port of its associated switch element, each circuit means including a first diode and series resistor coupling the first end of a secondary to the control input of its associated switch circuit, a second diode coupling the second end of the secondary to the control input, means for coupling the control return to the intermediate tap of the secondary, and a capacitor coupling the control input to the return; a second plurality n2 of circuit means, one circuit means being associated with each toroidal core of the second plurality n2, of toroidal cores and its corresponding switch element for coupling the secondary winding of its associated toroidal core to the control port of its associated switch element, each circuit means including a first diode and series resistor coupling the first end of a secondary to the control input of its associated switch circuit, a second diode coupling the second end of the secondary to the control input, means for coupling the control return to the intermediate tap of the secondary, and a capacitor coupling the control input to the return; a primary winding formed by an insulated wire element passing through all of the n toroidal cores (n=n1+n2) for coupling to an external control signal source for controlling the static high voltage switch; a pair of terminals for connection to the high voltage D.C. source and load, respectively; and first and second diode circuit means for coupling the terminals to the terminal ends of the first and second bridges, the diodes coupling the terminals to the two bridges being arranged in opposite polarity so that bidirectional operation of the static high voltage switch is made possible.