# hysteresis current control

Views:

Category: Entertainment

## Presentation Description

No description available.

By: prakashkumar1986 (84 month(s) ago)

this is very nice presentation

By: ramakrishna0245 (81 month(s) ago)

i want to see ur presentation

## Presentation Transcript

### Slide 1:

Single-Phase Diode Rectifier Bridge Large capacitor at the dc output for filtering and energy storage

### Slide 2:

Diode-Rectifier Bridge Analysis Two simple (idealized) cases to begin with

### Slide 3:

Waveforms with a purely resistive load and a purely dc current at the output In both cases, the dc-side voltage waveform is the same

### Slide 4:

Diode-Rectifier Bridge Input Current Idealized case with a purely dc output current

### Slide 5:

Diode-Rectifier Bridge Analysis with AC-Side Inductance Output current is assumed to be purely dc

### Slide 6:

Effect of DC-Side Current on THD, PF and DPF Very high THD at low current values

### Slide 7:

Diode-Rectifier with a Capacitor Filter Power electronics load is represented by an equivalent load resistance

### Slide 8:

Diode-Bridge Rectifier: Waveforms Analysis using PSpice

### Slide 9:

Analysis using PSpice Input Line-Current Distortion

### Slide 10:

Line-Voltage Distortion PCC is the point of common coupling

### Slide 11:

Distortion in voltage supplied to other loads Line-Voltage Distortion

### Slide 12:

Three-Phase, Full-Bridge Rectifier Commonly used

### Slide 13:

Three-Phase, Full-Bridge Rectifier: Redrawn Two groups with three diodes each

### Slide 14:

Three-Phase, Full-Bridge Rectifier Waveforms Output current is assumed to be dc

### Slide 15:

Three-Phase, Full-Bridge Rectifier: Input Line-Current Assuming output current to be purely dc and zero ac-side inductance

### Slide 16:

Three-Phase, Full-Bridge Rectifier Including the ac-side inductance

### Slide 17:

Rectifier with a Large Filter Capacitor Output voltage is assumed to be purely dc

### Slide 18:

Three-Phase, Full-Bridge Rectifier THD, PF and DPF as functions of load current

### Slide 19:

Harmonic Guidelines: IEEE 519 commonly used for specifying limits on the input current distortion

### Slide 20:

B. Hysteresis (Bang-bang) PWM (1) Three-phase inverter for hysteresis Current Control Fig. 8 Three-phase inverter for hysteresis current control. 15

### Slide 21:

II. PWM METHODS B. Hysteresis (Bang-bang) PWM (2) Hysteresis Current Controller Fig. 9 Hysteresis current controller at Phase “a”. 16

### Slide 22:

II. PWM METHODS B. Hysteresis (Bang-bang) PWM (3) Characteristics of hysteresis Current Control Advantages Drawbacks 17 Excellent dynamic response Low cost and easy implementation Large current ripple in steady-state Variation of switching frequency No intercommunication between each hysterisis controller of three phases and hence no strategy to generate zero-voltage vectors. As a result, the switching frequency increases at lower modulation index and the signal will leave the hysteresis band whenever the zero vector is turned on. The modulation process generates subharmonic components