HVDC
TRANSMISSION
Prepared By:
Gagandeep Kaur
 High voltage direct current (HVDC) power systems use D.C.
for transmission of bulk power over long distances.
INTRODUCTION
 For long-distance power transmission, HVDC lines are less
expensive, and losses are less as compared to AC
transmission.
 In a combined AC and DC system, generated AC voltage is
converted into DC at the sending end.
 Then, the DC voltage is inverted to AC at the receiving end, for
distribution purposes.
 Thus, the conversion and inversion equipment are also needed
at the two ends of the line.
INTRODUCTION
 HVDC transmission is economical only for long distance
transmission lines having a length more than 600kms and for
underground cables of length more than 50kms.
 In generating substation, AC power is generated which can be
converted into DC by using a rectifier.
 In HVDC substation or converter substation rectifiers and
inverters are placed at both the ends of a line.
How does HVDC
transmission
system work?
 The rectifier terminal changes the AC to DC, while the inverter
terminal converts DC to AC.
 The power remains the same at the sending and receiving ends
of the line.
 DC is transmitted over long distances because it decreases the
losses and improves the efficiency.
 When there are two converter stations at both ends and a single
transmission line is termed as two terminal DC systems.
How does HVDC
transmission
system work?
 When there are two or more converter stations and DC
transmission lines is termed as multi-terminal DC substation.
 EVOLUTION OF HVDC
 COMPARISON BETWEEN HVDC AND HVAC system
 Various problems in HVAC systems
 Advantages and Disadvantages
COURSE
CONTENT
 Various types of HVDC transmission system
 Components of HVDC transmission systel
 Evolution of HVDC Transmission
 Comparison of HVDC and HVAC systems
CHAPTER 1
 Types of HVDC transmission system
 Component of HVDC system
EVOLUTION
OF POWER
SYSTEM
EVOLUTION
OF POWER
SYSTEM
EVOLUTION
OF POWER
SYSTEM
HVDC System
• BULK power transmission
• POWER FLOW CONTROL
• To provide STABLITY
LIMITATIONS
OF
HVAC System
• Reactive power loss
• Stability
• Current carrying capability
• Skin effect & Ferranti effect
• Power flow control is not
possible
np+-1
6 pulse converter= 5,7 11, 13
ADVANTAGES • Cost of terminal Equipments is high
• Harmonics
OF
HVDC System • Blocking of reactive power
• Point to point transmission
• Limited overload
ADVANTAGES
OF
HVDC System
DISADVANTAGES
OF
HVDC System
TYPES OF
HVDC LINKS
TYPES OF
HVDC LINKS
Monopolar
Bipolar
homopolar
PRINCIPLE
PARTS OF HVDC
TRANSMISSION
SYSTEM
THREE PHASE
RECTIFIER
THREE PHASE
RECTIFIER
𝑃𝐼𝑉 = 3𝐸𝑚
p=3
THREE PHASE
RECTIFIER
THREE PHASE
RECTIFIER
THREE PHASE
RECTIFIER