Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
255 words
An electrical power converter arrangement comprising: a converter having positive side semiconductor switching elements connected in series and negative side semiconductor switching elements connected in series, said converter converting a DC voltage to an AC output phase voltage having at least three potential levels; and a control unit for controlling turn on and turn off of the positive side and negative side semiconductor switching elements of said converter to operate said converter dependent upon a voltage amplitude command input to said control unit for a fundamental wave in a first modulation mode in which the AC output phase voltage in a half cycle thereof is realized by alternating positive and negative output pulses and in a second modulation mode in which the AC output phase voltage in a half cycle thereof is realized by output pulses having only the same polarity as the corresponding fundamental modulation wave, wherein transition between the first modulation mode operation and the second modulation mode operation is performed via a third modulation mode in which the AC output phase voltage in a first period in a half cycle thereof is realized by alternating positive and negative output pulses and the AC output phase voltage in a second period in the half cycle thereof is realized by output pulses having only the same polarity as the corresponding fundamental modulation wave and the intervals of the first and second periods in the half cycle of the AC output phase voltage varies dependent upon the voltage amplitude command for the fundamental modulation wave.
Claim 2
Dependent Claim
255 words
An electrical power converter arrangement comprising: a converter having positive side semiconductor switching elements connected in series and negative side semiconductor switching elements connected in series, said converter converting a DC voltage to an AC output phase voltage having at least three potential levels; and a control unit for controlling turn on and turn off of the positive side and negative side semiconductor switching elements of said converter to operate said converter dependent upon a voltage amplitude command input to said control unit for a fundamental wave in a first modulation mode in which the AC output phase voltage in a half cycle thereof is realized by alternating positive and negative output pulses and in a second modulation mode in which the AC output phase voltage in a half cycle thereof is realized by output pulses having only the same polarity as the corresponding fundamental modulation wave, wherein transition between the first modulation mode operation and the second modulation mode operation is performed via a third modulation mode in which the AC output phase voltage in a first period in a half cycle thereof is realized by alternating positive and negative output pulses and the AC output phase voltage in a second period in the half cycle thereof is realized by output pulses having only the same polarity as the corresponding fundamental modulation wave and the intervals of the first and second periods in the half cycle of the AC output phase voltage varies dependent upon the voltage amplitude command for the fundamental modulation wave.
Claim 3
Dependent Claim
113 words
An electrical power converter arrangement according to claim 1, wherein said control unit comprises: first means for preparing the fundamental modulation wave based upon the voltage amplitude command and a frequency command to be output from an inverter; second means for preparing a positive biased modulation wave and a negative biased modulation wave dependent upon the voltage amplitude command; third means for preparing a positive side modulation wave and a negative side modulation wave dependent upon both the positive and negative biased modulation waves; and fourth means for generating pulse width modulation pulse trains for the positive side and negative side semiconductor switching elements based upon the positive and negative side modulation waves.
Claim 4
Dependent Claim
69 words
An electrical power converter arrangement according to claim 2, wherein said third means produces the positive side modulation wave by adding a positive component of the negative biased modulation wave to the positive component of the positive biased modulation wave (ap1*) and produces the negative side modulation wave by adding a negative component of the positive biased modulation wave to the negative component of the negative biased modulation wave.
Claim 5
Dependent Claim
115 words
An electrical power converter arrangement according to claim 2, wherein said third means suppresses outputting of the positive and negative side modulation wave below predetermined positive and negative values which produce a pulse having a width corresponding to the minimum "on" time of the positive side and negative side semiconductor switching elements, and produces the positive side modulation wave by adding a component of the negative biased modulation wave above the predetermined negative value to the unsuppressed component of the positive biased modulation wave and the negative side modulation wave by adding a component of the positive biased modulation wave below the predetermined positive value to the unsuppressed component of the negative biased modulation wave.
Claim 6
Dependent Claim
56 words
An electrical power converter arrangement according to claim 2, wherein said fourth means are applied to reference clock signals CK for determining timing of the pulse generation therefrom, and the frequency of the reference clock signals CK is adapted to increase in accordance with the increase of the voltage amplitude command for the fundamental modulation wave.
Claim 7
Dependent Claim
117 words
An electrical power converter arrangement according to claim 1, wherein: said control unit comprises: first means for preparing the fundamental modulation wave based upon the voltage amplitude command and frequency command to be outputted from an inverter; second means for preparing a positive biased modulation wave and a negative biased modulation wave dependent upon the voltage amplitude command; third means for preparing a positive side modulation wave dependent upon the both positive and negative biased modulation waves and a negative side modulation wave dependent upon the both positive and negative biased modulation waves; and fourth means for generating pulse width modulation pulse trains for the semiconductor switching elements based upon the positive and negative side modulation waves.
Claim 8
Dependent Claim
66 words
An electrical power converter arrangement according to claim 2, wherein said third means produces the positive side modulation wave by adding a positive component of the negative biased modulation wave to the positive component of the positive biased modulation wave and the negative side modulation wave by adding negative component of the positive biased modulation wave to the negative component of the negative biased modulation wave.
Claim 9
Dependent Claim
110 words
An electrical power converter arrangement according to claim 2, wherein said third means suppresses outputting of the positive and negative side modulation wave below predetermined positive and negative values which produce a pulse having a width corresponding to the minimum on time of the semiconductor switching elements, and produces the positive side modulation wave by adding a component of the negative biased modulation wave above the predetermined negative value to the unsuppressed component of the positive biased modulation wave and the negative side modulation wave by adding a component of the positive biased modulation wave below the predetermined positive value to the unsuppressed component of the negative biased modulation wave.
Claim 10
Dependent Claim
54 words
An electrical power converter arrangement according to claim 2, wherein said fourth means are applied of reference clock signals for determining timing of the pulse generation therefrom and the frequency of the reference clock signals is adapted to increase in accordance with the increase of the voltage amplitude command for the fundamental modulation wave.
Claim 11
Dependent Claim
259 words
An electrical power converter comprising: a converter having positive side semiconductor switching elements connected in series and negative side semiconductor switching elements connected in series, which converts a DC voltage to an AC output phase voltage having at least three potential levels; a control unit for said converter which turns said semiconductor switching elements on and off to operate said converter; wherein said converter operates dependent upon a voltage amplitude command inputted to said control unit for a fundamental modulation wave in a plurality of modulation modes; and wherein said plurality of modulation modes comprise a first modulation mode in which the AC output phase voltage in a half cycle thereof is realized by alternating positive and negative output pulses, a second modulation mode in which the AC output phase voltage in a half cycle thereof is realized by output pulses having only the same polarity as the corresponding fundamental modulation wave, wherein transition between said first modulation mode and said second modulation mode operation is performed via a third modulation mode in which the AC output phase voltage in a first period in a half cycle thereof is realized by alternating positive and negative output pulses and the AC output phase voltage in a second period in the half cycle thereof is realized by output pulses having only the same polarity as the corresponding fundamental modulation wave and the intervals of the first and second periods in the half cycle of the AC output phase voltage varies dependent upon the voltage amplitude command for the fundamental modulation wave.
Claim 12
Dependent Claim
259 words
An electrical power converter comprising: a converter having positive side semiconductor switching elements connected in series and negative side semiconductor switching elements connected in series, which converts a DC voltage to an AC output phase voltage having at least three potential levels; a control unit for said converter which turns said semiconductor switching elements on and off to operate said converter; wherein said converter operates dependent upon a voltage amplitude command inputted to said control unit for a fundamental modulation wave in a plurality of modulation modes; and wherein said plurality of modulation modes comprise a first modulation mode in which the AC output phase voltage in a half cycle thereof is realized by alternating positive and negative output pulses, a second modulation mode in which the AC output phase voltage in a half cycle thereof is realized by output pulses having only the same polarity as the corresponding fundamental modulation wave, wherein transition between said first modulation mode and said second modulation mode operation is performed via a third modulation mode in which the AC output phase voltage in a first period in a half cycle thereof is realized by alternating positive and negative output pulses and the AC output phase voltage in a second period in the half cycle thereof is realized by output pulses having only the same polarity as the corresponding fundamental modulation wave and the intervals of the first and second periods in the half cycle of the AC output phase voltage varies dependent upon the voltage amplitude command for the fundamental modulation wave.