Quasi-resonant pole inverter

• US 5,717,584 A
• Filed: 12/08/1995
• Issued: 02/10/1998
• Est. Priority Date: 12/08/1995
• Status: Expired due to Fees

• Current Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Original Assignee: General Motors Corporation (Motors Liquidation Co. GUC Trust)
• Inventors: Rajagopalan, Venkatachari, Rajashekara, Kaushik
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): Riley, Shawn
• Application Number:
  US08/569,856
• Time in Patent Office: 795 Days
• Field of Search: 363/37, 363/41, 363/95, 363/97, 363/98, 363/131, 363/132, 363/56, 363/71, 318/800, 318/801, 318/803
• US Class Current: 363/98
• CPC Class Codes: H02M 7/4811 having auxiliary actively switched resonant commutation circuits connected to intermediate DC voltage or between two push-pull branches
• CPC Class Codes: H02M 7/5387 in a bridge configuration
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A quasi-resonant pole inverter provides soft-switching of the main inverter switch devices only when such opportunities are required by the pulse width modulation control. The inverter includes a main switching section and an auxiliary switching section. A phase-pole of the main switching section swings from source to ground potential with the assistance of the auxiliary switching section. The phase-pole swings from ground to source potential with the assistance of the auxiliary switching section. Low switch stresses are characteristic in both the main switching section devices and the auxiliary section switching devices. Main power is carried predominantly through the DC rails thereby minimizing power handling requirements of quasi-resonant reactive components.

Claims

1. A soft-switched, multi-phase, quasi-resonant pole inverter comprising:

a DC source including a positive DC rail at a first voltage and a negative DC rail at a second voltage, a multi-phase main switching section including a plurality of phase-pairs of main switch devices between said positive and negative DC rails, each one of said plurality of phase-pairs of main switch devices including an upper and a lower main switch device and a respective main phase-pole therebetween, an auxiliary switching section including one pair of auxiliary switch devices between said positive and negative DC rails including an upper and a lower auxiliary switch device and an auxiliary pole therebetween, and a plurality of series combined inductor and capacitor pairs, each one of said plurality of series combined inductor and capacitor pairs coupled between the auxiliary pole and a respective one of said main phase-poles.

2. A soft-switched, multi-phase, quasi-resonant pole inverter as claimed in claim 1 wherein each upper and lower main switch device includes a respective solid state main switch and each upper and lower auxiliary switch device including a respective solid state auxiliary switch, each main and auxiliary switch having a respective anti-parallel diode coupled thereacross, each main switch further having a capacitor coupled thereacross, said inverter further comprising a control for executing a quasi-resonant cycle of a predetermined main phase-pole by sequentially commanding on the lower auxiliary switch to catalyze a swing of the predetermined main phase-pole to the negative DC rail voltage, commanding off the upper main switch corresponding to the predetermined main phase-pole to release the predetermined main phase-pole from the positive DC rail voltage to thereby swing the predetermined main phase-pole to the negative DC rail voltage, commanding on the lower main switch corresponding to the predetermined main phase-pole while the respective anti-parallel diode is forward biased, commanding off the lower auxiliary switch while the respective anti-parallel diode is forward biased, commanding on the upper auxiliary switch to catalyze a swing of the predetermined main phase-pole to the positive DC rail voltage, commanding off the lower main switch corresponding to the predetermined main phase-pole to release the predetermined main phase-pole from the negative DC rail voltage to thereby swing the predetermined main phase-pole from the negative DC rail voltage to the positive DC rail voltage, commanding on the upper main switch while the respective anti-parallel diode is forward biased, and commanding off the upper auxiliary switch corresponding to the predetermined main phase-pole while the respective anti-parallel diode is forward biased.

3. A method of executing a quasi-resonant cycle of a predetermined main phase-pole of a quasi-resonant pole inverter having a DC source including a positive DC rail and a negative DC rail, a multi-phase main switching section including a plurality of phase-pairs of main switch devices between said positive and negative DC rails, each one of said plurality of phase-pairs of main switch devices including a respective main phase-pole between an upper and a lower solid state main switch, each main switch having a respective anti-parallel diode and capacitor coupled thereacross, an auxiliary switching section including one pair of auxiliary switch devices between said positive and negative DC rails including an auxiliary pole between an upper and a lower solid state auxiliary switch, each auxiliary switch having a respective anti-parallel diode coupled thereacross, and a plurality of series combined inductor and capacitor pairs, each one of said plurality of series combined inductor and capacitor pairs coupled between the auxiliary pole and a respective one of said main phase-poles, the method comprising the steps of:

commanding on the lower auxiliary switch to catalyze a swing of the predetermined main phase-pole to the negative DC rail voltage, commanding off the upper main switch corresponding to the predetermined main phase-pole to release the predetermined main phase-pole from the positive DC rail voltage to thereby swing the predetermined main phase-pole to the negative DC rail voltage, commanding on the lower main switch corresponding to the predetermined main phase-pole while the respective anti-parallel diode is forward biased, commanding off the lower auxiliary switch while the respective anti-parallel diode is forward biased, commanding on the upper auxiliary switch to catalyze a swing of the predetermined main phase-pole to the positive DC rail voltage, commanding off the lower main switch corresponding to the predetermined main phase-pole to release the predetermined main phase-pole from the negative DC rail voltage to thereby swing the predetermined main phase-pole from the negative DC rail voltage to the positive DC rail voltage, commanding on the upper main switch corresponding to the predetermined main phase-pole while the respective anti-parallel diode is forward biased, and commanding off the upper auxiliary switch while the respective anti-parallel diode is forward biased.

4. A soft-switched, multi-phase, quasi-resonant pole inverter comprising:

a DC source including a positive DC rail at a first voltage and a negative DC rail at a second voltage, a multi-phase main switching section including a plurality of phase-pairs of main switch devices between said positive and negative DC rails, each one of said plurality of phase-pairs of main switch devices including an upper and a lower main switch device and a respective main phase-pole therebetween, an auxiliary switching section including a plurality of phase-pairs of auxiliary switch devices between said positive and negative DC rails, each one of said plurality of phase-pairs of auxiliary switch devices including an upper and a lower auxiliary switch device and a respective auxiliary phase-pole therebetween, and a plurality of series combined inductor and capacitor pairs, each one of said plurality of series combined inductor and capacitor pairs coupled between a respective one of said auxiliary phase-poles and a respective one of said main phase-poles.

5. A soft-switched, multi-phase, quasi-resonant pole inverter as claimed in claim 4 wherein each upper and lower main switch device includes a respective solid state main switch and each upper and lower auxiliary switch device includes a respective solid state auxiliary switch, each main and auxiliary switch having a respective anti-parallel diode coupled thereacross, each main switch further having a capacitor coupled thereacross, said inverter further comprising a control for executing a quasi-resonant cycle of a predetermined phase-pole by sequentially commanding on the lower auxiliary switch to catalyze a swing of the predetermined main phase-pole to the negative DC rail voltage, commanding off the upper main switch corresponding to the predetermined main phase-pole to release the predetermined main phase-pole from the positive DC rail voltage to thereby swing the predetermined main phase-pole to the negative DC rail voltage, commanding on the lower main switch corresponding to the predetermined main phase-pole while the respective anti-parallel diode is forward biased, commanding off the lower auxiliary switch while the respective anti-parallel diode is forward biased, commanding on the upper auxiliary switch to catalyze a swing of the predetermined main phase-pole to the positive DC rail voltage, commanding off the lower main switch corresponding to the predetermined main phase-pole to release the predetermined main phase-pole from the negative DC rail voltage to thereby swing the predetermined main phase-pole from the negative DC rail voltage to the positive DC rail voltage, commanding on the upper main switch while the respective anti-parallel diode is forward biased, and commanding off the upper auxiliary switch corresponding to the predetermined main phase-pole while the respective anti-parallel diode is forward biased.

6. A method of executing a quasi-resonant cycle of a predetermined main phase-pole of a quasi-resonant pole inverter having a DC source including a positive DC rail and a negative DC rail, a multi-phase main switching section including a plurality of phase-pairs of main switch devices between said positive and negative DC rails, each one of said plurality of phase-pairs of main switch devices including a respective main phase-pole between an upper and a lower solid state main switch, each main switch having a respective anti-parallel diode and capacitor coupled thereacross, an auxiliary switching section including a plurality of phase-pairs of auxiliary switch devices between said positive and negative DC rails, each one of said plurality of phase-pairs of auxiliary devices including a respective auxiliary phase-pole between an upper and a lower solid state auxiliary switch, each auxiliary switch having a respective anti-parallel diode coupled thereacross, and a plurality of series combined inductor and capacitor pairs, each one of said plurality of series combined inductor and capacitor pairs coupled between the auxiliary phase-pole and a respective one of said main phase-poles, the method comprising the steps of:

commanding on the lower auxiliary switch to catalyze a swing of the predetermined main phase-pole to the negative DC rail voltage, commanding off the upper main switch corresponding to the predetermined main phase-pole to release the predetermined main phase-pole from the positive DC rail voltage to thereby swing the predetermined main phase-pole to the negative DC rail voltage, commanding on the lower main switch corresponding to the predetermined main phase-pole while the respective anti-parallel diode is forward biased, commanding off the lower auxiliary switch while the respective anti-parallel diode is forward biased, commanding on the upper auxiliary switch to catalyze a swing of the predetermined main phase-pole to the positive DC rail voltage, commanding off the lower main switch corresponding to the predetermined main phase-pole to release the predetermined main phase-pole from the negative DC rail voltage to thereby swing the predetermined main phase-pole from the negative DC rail voltage to the positive DC rail voltage, commanding on the upper main switch corresponding to the predetermined main phase-pole while the respective anti-parallel diode is forward biased, and commanding off the upper auxiliary switch while the respective anti-parallel diode is forward biased.