Inverter controller
AssigneeMitsubishi Electric Corporation
InventorHisanori Yamasaki
Life of this patent
Estimating the term…
Abstract
A PWM operation unit includes a modulation-mode selecting unit selecting a two-phase modulation mode signal and a carrier-wave-synchronous-mode select command, a modulation-wave generating unit generating a modulation wave in response to the two-phase modulation mode signal, a carrier-wave generating unit generating a carrier wave in response to the carrier-wave-synchronous-mode select command, and a comparing unit comparing the modulation wave with the carrier wave. In a two-phase modulation mode, the PWM operation unit controls the carrier-wave generating unit such that a carrier wave frequency is set to an integral multiple of a modulation wave frequency.
Claims17
An inverter controller comprising:
- an inverter main circuit that supplies a power to a three-phase load;
- and
- a pulse-width-modulation operation unit that outputs a switching command to the inverter main circuit, wherein
- the pulse-width-modulation operation unit includes
- a modulation-mode selecting unit that selects an optimal two-phase modulation mode signal for modulation and a carrier-wave-synchronous-mode select command based on information on a voltage command value for applying a voltage to the three-phase load,
- a modulation-wave generating unit that generates a modulation wave as a voltage command value to the inverter main circuit in response to the two-phase modulation mode signal,
- a carrier-wave generating unit that generates a carrier wave that becomes a reference for the switching command in response to the carrier-wave-synchronous-mode select command, and
- a comparing unit that compares the modulation wave and the carrier wave and determines a switching pattern based on a result of comparison, and
- in a two-phase modulation mode in which switching of any one of three phases configuring the inverter main circuit is turned off, the pulse-width-modulation operation unit controls the carrier-wave generating unit such that a carrier wave frequency that is a frequency of the carrier wave is set to an integral multiple of a modulation wave frequency that is a frequency of the modulation wave.
An inverter controller comprising:
- an inverter main circuit that supplies a power to a three-phase load;
- and
- a pulse-width-modulation operation unit that outputs a switching command to the inverter main circuit, wherein
- the pulse-width-modulation operation unit includes
- a modulation-wave generating unit that generates a modulation wave as a voltage command value to the inverter main circuit,
- a carrier-wave generating unit that generates a carrier wave that becomes a reference for the switching command, and
- a comparing unit that compares the modulation wave and the carrier wave and determines a switching pattern based on a result of comparison, and
- in a two-phase modulation mode in which switching of any one of three phases configuring the inverter main circuit is turned off, the pulse-width-modulation operation unit controls the carrier-wave generating unit such that a carrier wave frequency that is a frequency of the carrier wave is set to an integral multiple of a modulation wave frequency that is a frequency of the modulation wave, and changes over a ratio of the carrier wave frequency to the modulation wave frequency by time of one cycle of the modulation wave while maintaining a condition that the carrier wave frequency is an integral multiple of the modulation wave frequency.
Dependencies are inferred from the claim text.