Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
120 words
A method of operating an inverter having a constant DC input voltage and an AC output voltage having a controlled fundamental frequency during pulse operation with voltage time integrals resulting in an approximately sinusoidal current curve, and having a conductance dependent on the output frequency and having a switching component having a conductive condition in which it conducts current and a nonconductive condition in which it prevents current conduction, said method comprising preventing the operation of the switching component so that said switching component is prevented from being changed to its nonconductive condition thereby bridging the shortest noncurrent interval in a half-cycle of the output voltage when the duration of the noncurrent interval decreases to less than a predetermined magnitude.
Claim 2
Independent Claim
120 words
A method of operating an inverter having a constant DC input voltage and an AC output voltage having a controlled fundamental frequency during pulse operation with voltage time integrals resulting in an approximately sinusoidal current curve, and having a conductance dependent on the output frequency and having a switching component having a conductive condition in which it conducts current and a nonconductive condition in which it prevents current conduction, said method comprising preventing the operation of the switching component so that said switching component is prevented from being changed to its nonconductive condition thereby bridging the shortest noncurrent interval in a half-cycle of the output voltage when the duration of the noncurrent interval decreases to less than a predetermined magnitude.
Claim 3
Dependent Claim
21 words
A method as claimed in claim 1, wherein a plurality of successive noncurrent intervals of the voltage time integrals are bridged.
Claim 4
Dependent Claim
48 words
A method as claimed in claim 1, wherein preventing the operation of the switching component so that said switching component is prevented from being changed to its nonconductive condition bridges a plurality of successive noncurrent intervals when the duration of a noncurrent interval reaches an adjustable minimum value.
Claim 5
Dependent Claim
37 words
A method as claimed in claim 1, wherein the voltage time integrals and the noncurrent intervals are so determined that the selected pulse frequency is a whole number multiple of the frequency of the AC output voltage.
Claim 6
Dependent Claim
25 words
A method as claimed in claim 1, wherein a plurality of successive voltage time integrals are bridged stepwise at predetermined values of the output frequency.
Claim 7
Dependent Claim
38 words
A method as claimed in claim 1, wherein the inverter is connected to a rotary field machine and the output voltage is selected at predetermined values of the output frequency to produce a rated flux in the machine.
Claim 8
Dependent Claim
32 words
A method as claimed in claim 3, wherein the switching of the switching component to its nonconductive condition is permitted only when a noncurrent interval of longer than minimum duration is required.
Claim 9
Dependent Claim
42 words
A method as claimed in claim 5, wherein at approximately the same magnitudes of the output frequency the ratio of abrupt variation of the AC output voltage to its fundamental frequency remains approximately constant for the entire range of stepwise frequency variation.
Claim 10
Dependent Claim
23 words
A method as claimed in claim 5, wherein the voltage time integrals and noncurrent intervals are varied in duration within the predetermined values.
Claim 11
Dependent Claim
31 words
A method as claimed in claim 6, wherein the correspondence of the frequency steps to the values of the output voltage is varied in accordance with the load of the machine.
Claim 12
Dependent Claim
14 words
A method as claimed in claim 8, wherein the ratio is less than 20:100.
Claim 13
Dependent Claim
14 words
A method as claimed in claim 8, wherein the ratio is less than 10:100.
Claim 14
Dependent Claim
13 words
A method as claimed in claim 8, wherein the ratio is about 6:100.
Claim 15
Dependent Claim
138 words
An inverter system comprising an inverter network having a constant DC input voltage circuit and an AC output voltage circuit having a controlled fundamental frequency during pulse operation with voltage time integrals resulting in an approximately sinusoidal current curve, said network having a conductance dependent on the output frequency and comprising a switching component having a conductive condition and a nonconductive condition, said inverter system comprising pulse-shaping means for producing a quenching pulse for changing said switching component to its nonconductive condition; time-comparing means coupled to said pulse-shaping means for comparing said quenching pulse in duration to a predetermined reference time interval; and suppressing means coupled to said time-comparing means for preventing the application of said quenching pulse to said switching component as long as the duration of said quenching pulse is less than said reference time interval.
Claim 16
Dependent Claim
138 words
An inverter system comprising an inverter network having a constant DC input voltage circuit and an AC output voltage circuit having a controlled fundamental frequency during pulse operation with voltage time integrals resulting in an approximately sinusoidal current curve, said network having a conductance dependent on the output frequency and comprising a switching component having a conductive condition and a nonconductive condition, said inverter system comprising pulse-shaping means for producing a quenching pulse for changing said switching component to its nonconductive condition; time-comparing means coupled to said pulse-shaping means for comparing said quenching pulse in duration to a predetermined reference time interval; and suppressing means coupled to said time-comparing means for preventing the application of said quenching pulse to said switching component as long as the duration of said quenching pulse is less than said reference time interval.