If a small DC-link capacitor is used in the DC-link fed by single phase AC source, the DC-link voltage fluctuates severely with twice of the source frequency. To handle this fluctuation, the concept of `average voltage constraint' is proposed in this study. On the basis of the concept, a flux weakening scheme generating d-axis current reference (idsr*) for Interior Permanent Magnet Synchronous Machine (IPMSM) is devised. And, q-axis current reference (iqsr*) is modified for the unity power factor operation to AC source. The proposed scheme has been applied to inverter driven 1 kW compressor of an air-conditioner. From the experimental results, it has been verified that the compressor operates well at required operating condition regardless of the severe fluctuation of DC-link voltage due to the reduced DC-link capacitor. Also the frequency spectrum of the AC source current reveals that the harmonics of the source current meet IEC 61000-3-2 Class A and that the overall power factor is above 97% without any additional circuit such as an input filter and the power factor correction circuit.
[1]
Remus Teodorescu,et al.
A New Single-Phase PLL Structure Based on Second Order Generalized Integrator
,
2006
.
[2]
Peter Mutschler,et al.
Permanent magnet drives with reduced dc-link capacitor for home appliances
,
2009,
2009 35th Annual Conference of IEEE Industrial Electronics.
[3]
T.G. Habetler,et al.
Condition Monitoring of Electrolytic Capacitor in Power Electronic Circuits using Adaptive Filter Modeling
,
2005,
2005 IEEE 36th Power Electronics Specialists Conference.
[4]
Isao Takahashi,et al.
Power factor improvement of single‐phase diode rectifier circuit by field‐weakening of inverter‐driven IPM motor
,
2005
.