NEW HYBRID POWER CONDITIONER

1. SILPA V
S7 F
ROLL NO: 58
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2. • Introduction
• Before hybrid power conditioner
• Hybrid power conditioner
• New hybrid power conditioner
• Three phase four wire hybrid filter
• System configuration
• Control principle
• Control block diagram
• Experimental results
• Advantages
• Applications
• Conclusions
• References
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3. Proposed for suppressing harmonic currents and neutral
line current.
Employed in three phase four wire distribution system.
Consists of neutral line current attenuator and a hybrid
power filter.
Hybrid power filter consists of three phase power
convertor and three phase tuned power filter.
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4.  Zig-zag transformer: Connected to the load in
parallel depends the ratio between utility and zig-zag
transformer
 Zig-zag transformer with single phase power converter :
inserted at neutral line fluctuation in the ground voltage of
the load
 Series of active power filters: connected to the neutral line
between the utility and load fluctuation in ground voltage of
the load
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5.  Passive power filters :advantage of low hardware cost, affected
by system impedance, large volume, parallel resonance and
series resonance
 Power semiconductor technology : Active power filters
suppress the neutral line current capacity and manufacturing
cost of power converter is very high
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 Developed to solve the problems of active and passive power
conditioners
 HPF consists of passive power filter and a power converter
 Passive power filter reduce the capacity of power converter
 Power converter improve the filter characteristics of
passive power filter
 HPF is divided into series linked and shunt linked type

7.  Power converter connected between the utility and load
through a linked transformer in series linked type.
 Passive power filter is parallel to the load
 Power converter is connected to the passive power filter in
series and then connected to load in parallel in shunt type.
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8.  Hybrid power conditioner: 1. neutral line current attenuator,
2. hybrid power filter.
 Hybrid power filter : 1. three phase power converter, 2. three
phase tuned power filter
 Neutral line current attenuator to attenuate neutral line current
 Can effectively reduce the power rating of passive and active
elements
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9. Fig 1. Configuration of the conventional shunt type hybrid filter
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10.  Configuration of a conventional shunt type hybrid power filter.
 Power converter series with power filter connected to
the load in parallel.
 Passive power filter three phase tuned power filters with an
inductor and a capacitor connected in series.
 Utility voltage drop on the passive power filter dc bus
voltage and voltage rating reduced harmonic current and
fundamental reactive currents not diminished.
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11. Fig.2 Configuration of the advanced hybrid power filter
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12. To reduce the power rating of the power converter.
Power convertor connected to the inductors of the three phase
tuned power filter in parallel.
Reactive current and harmonic current flows through the inductors
decreasing the current flowing through the power converter.
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13.  Major role is to filter the harmonic currents of the load.
 Neutral line current of the load contains a fundamental
component in unbalanced three phase loads.
 Conventional type cannot suppress the neutral line current
under the unbalanced load.
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14. Fig 3. System configuration
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15.  A neutral line current attenuator is integrated into the hybrid
filter
 Advance the filter performance under the unbalanced load
 With an increase in tuned frequency of the tuned power filters
volume and weight of the tuned power filter reduced
 Neutral line current attenuator phase voltage drop on
capacitors volume and weight of the transformer reduced
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16.  Current mode control-to control the three phase power
converter of the hybrid power filter
 Ica= K1Isah+K2VSA1
 Icb=K1Isbh+K2Vsb1
 Icc=K1Isch+K2Vsc1
 Isah, Isbh , Isch = harmonic components of the three phase utility
currents.
 VSA1 , Vsb1 Vsc1 =three phase fundamental voltages of the
utility.
 First term - suppress the non zero sequence harmonics
 Second term - regulate the dc bus voltage
 Reactive current of tuned power filters and harmonic currents
of the load-flows through the inductors - suppression attained
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17.  Feedforward control- adopts in single phase power converter
 Vcon=kcon Vm
 kcon = gain of the single phase converter
 Vm =modulation signal of the PWM circuit.
 The gain of the single phase converter is
 kcon=Vdc/Vtri
 Vdc = bus voltage
 Vtri = amplitude of the carrier of the PWM circuit.
 Neutral line current of the utility is detected, amplified and
sent to PWM circuit.
 Vcon= kconk3Isn , k3 =feedforward gain
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18. Fig 4.Control block diagram of the three phase and single phase
power converters
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19.  The current references contain fundamental signal and
harmonic signal
 The band stop filters are used to extract harmonic signals
 Fundamental signal is obtained as the result from the
multiplier
 The current references are sent to controllers
 The output of controllers sent to PWM circuit
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20.  To control single phase converter
 Neutral line current obtained by summing up detected three
phase utility currents
 Output of amplifier circuit sent to PWM circuit
 The control blocks of three phase and single phase power
converters can integrated into a digital signal processor chip
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21. Fig 4. Main parameters of the prototype
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22. Fig 5. Balanced three phase load and hybrid power conditioner
under the balanced three phase load
Total harmonic distortion of the load current is 47% and neutral
line current of load is 11.2A
Shows the utility currents after being compensated by HPC
The three phase utility current are nearly sinusoidal and THD is
3.9% and neutral line current is .81A
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23. Fig 6. Results of unbalanced three phase load and hybrid power
conditioner under the unbalanced three phase load
The results of unbalanced three phase load currents and neutral
load current
Only a single phase rectifier is applied between the phase a and
neutral line
Three phase utility currents are sinusoidal and THD are 7.35%
, 4.71% and 3.23% res. And neutral line current is .96A
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24.  Enhancing operation efficiency
 The power capacity of power converters in the hybrid power
filter and neutral line current attenuator can be effectively
reduced
 Suppress neutral line current and harmonic currents
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25.  Three phase four wire distribution systems applied to low
voltage applications
 Applicable whether the load is balanced or not
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26.  A new hybrid power conditioner composed of a hybrid power
filter and a neutral line current attenuator is proposed.
 Power capacity of power converters reduced and enhancing
the operation efficiency
 Effective solution to the problems of harmonic currents and
neutral line current in three phase four wire distribution
system
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27. [1]Jinn-Chang Wu,Hurng –Liahng Jou and Shun- Tian Xiao, “A
new hybrid power conditioner for suppressing harmonics and
neutral line current in three phase four wire distribution power
systems,”, IEEE Trans. Power Del., vol.29,no. 4 Aug 2014.
[2]B Singh, P. Jayaprakash and D.P.Kothari, “Reduced rating
VSC with a zig-zag transformer for current compensation in a
three phase four wire distribution system,” IEEE Trans. Power
Del., vol.24,no. 1,pp. 249-259,Jan. 2009.
[3]R. M.Ciric, L.F.Ochoa , A. Padilla-Feltrin and H. Nouri ,
“Fault analysis in four wire distribution networks,” Proc. Inst.
Elect .Eng., Gen., Transm . Distrib ., vol. 152,no.6,pp.977-
982,2005.
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