Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
139 words
A protection arrangement for use in protecting the valves in the valve branches of an inverter, the inverter being of a type having first and second fuses connected in series with its respective first and second d-c inputs, which inputs are adapted to receive a d-c input voltage, and of a type having a control unit for delivering firing pulses to said valve branches, said protection arrangement comprising: an electronic voltage monitoring device for monitoring said d-c input voltage by monitoring the voltage across two points each situated between one of said fuses and the d-c input to which said one fuse is connected, said device including means for delivering a protection signal to said control unit for causing said control unit to release firing pulses to said valve branches when said monitored voltage drops below a predetermined value.
Claim 2
Dependent Claim
139 words
A protection arrangement for use in protecting the valves in the valve branches of an inverter, the inverter being of a type having first and second fuses connected in series with its respective first and second d-c inputs, which inputs are adapted to receive a d-c input voltage, and of a type having a control unit for delivering firing pulses to said valve branches, said protection arrangement comprising: an electronic voltage monitoring device for monitoring said d-c input voltage by monitoring the voltage across two points each situated between one of said fuses and the d-c input to which said one fuse is connected, said device including means for delivering a protection signal to said control unit for causing said control unit to release firing pulses to said valve branches when said monitored voltage drops below a predetermined value.
Claim 3
Dependent Claim
81 words
A protection arrangement in accordance with claim 1 in which the inverter to be protected is included in a cycloconverter which compirses in addition to the inverter, an intermediate d-c link connected to the inverter and a rectifier connected to the intermediate d-c link and supplied by a supply network, and in which said voltage monitoring device further includes: a blocking gate adapted to block the delivery of said protection signal for a predetermined period during the starting-up of said cycloconverter.
Claim 4
Dependent Claim
88 words
A protection arrangement in accordance with claim 1 in which the inverter to be protected is included in a cycloconverter which comprises, in addition to the inverter, an intermediate d-c link connected to the inverter and a rectifier connected to the intermediate d-c link and supplied by a supply network, and in which said voltage monitoring device further includes: a blocking gate adapted to block the delivery of said protection signal as a function of the output signal of a voltage indicator indicating the intermediate link d-c voltage.
Claim 5
Dependent Claim
38 words
A protection arrangement in accordance with claim 1 in which said voltage monitoring device monitors said input voltage by monitoring the voltages between said fuses at the points at which said fuses are connected to said d-c inputs.
Claim 6
Dependent Claim
67 words
A protection arrangement in accordance with claim 1 in which said monitoring device further includes: a threshold member comprising a Zener diode; and a potential-free transmission device for converting the output signal of said member to said protection signal, said potential-free transmission device comprising an opto-electronic coupler which includes: a light emitting semiconductor element; a light-sensitive semiconductor element; and light guides separating said light-emitting and light-sensitive elements.
Claim 7
Dependent Claim
115 words
A protection arrangement for use in protecting the valves in the valve branches of an inverter, the inverter being of a type having first and second fuses connected in series with its respective first and second d-c inputs, which inputs are adapted to receive a d-c input voltage, and of a type having a control unit for delivering firing pulses to said branches, said protection arrangement comprising: an electronic voltage monitoring device for monitoring the voltages across each of said fuses and including means for delivering a protection signal to said control unit for causing said control unit to release firing pulses to said valve branches when a voltage being monitored exceeds a predetermined value.
Claim 8
Dependent Claim
115 words
A protection arrangement for use in protecting the valves in the valve branches of an inverter, the inverter being of a type having first and second fuses connected in series with its respective first and second d-c inputs, which inputs are adapted to receive a d-c input voltage, and of a type having a control unit for delivering firing pulses to said branches, said protection arrangement comprising: an electronic voltage monitoring device for monitoring the voltages across each of said fuses and including means for delivering a protection signal to said control unit for causing said control unit to release firing pulses to said valve branches when a voltage being monitored exceeds a predetermined value.
Claim 9
Dependent Claim
68 words
A protection arrangement in accordance with claim 6 in which said monitoring device further includes: a threshold member comprising a Zener diode; and a potential-free transmission device for converting the output signal of said member to said protection signal, said potential-free transmission device comprising an electronic coupler which includes: a light-emitting semiconductor element; a light-sensitive semiconductor element; and light guides separating said light emitting and light sensitive elements.