CTS Technology
Enertechnos has developed a disruptive power delivery technology: the first fundamental change to power cable design and fabrication in decades
Capacitive Transfer System (CTS)
Capacitive Transfer System (CTS) is an innovative concept for power cables design, introducing a “linear capacitor” through the cable length leading to lower losses and allowing delivery of more power than equivalent legacy cable systems.
Originally developed for electricity distribution networks, Enertechnos has refined CTS to be applicable in a wider area of applications, in offshore grids, wireless EV charging, aviation and other sectors.
To minimise the risk of adoption for our solutions, we optimised CTS to be manufactured on conventional cable-making equipment; developed jointing methods; and designed a cable protection system.
Capacitive Transfer System (CTS)
Capacitive Transfer System (CTS) is an innovative concept for power cables design, introducing a “linear capacitor” through the cable length leading to lower losses and allowing delivery of more power than equivalent legacy cable systems.
Originally developed for electricity distribution networks, Enertechnos has refined CTS to be applicable in a wider area of applications, in offshore grids, wireless EV charging, aviation and other sectors.
To minimise the risk of adoption for our solutions, we optimised CTS to be manufactured on conventional cable-making equipment; developed jointing methods; and designed a cable protection system.
Comparison: Conventional Cable and CTS
Conventional Cable
CTS Cable
In a cable the power it’s capable of transmitting is mainly defined by the system voltage and conductor impedance. Impedance consists of two distance-dependant parameters: resistance and inductive reactance, that increase with the power frequency. As impedance increases with the distance the cable can reach its limit, thus forcing users to go for higher voltages or thicker cables.
To combat this inductive reactance, CTS cable is designed to form its conductor into two “electrodes” along the entire length. One electrode is connected to the generator and the other is connected to the load. In this way the CTS cable acts as a capacitor offsetting most of the inductive reactance, leaving very nearly only the resistance part of impedance.
Voltage Drop
Voltage drop between the generation and load is a limiting factor for how long the cable line can be. With reduced voltage, a given load will draw greater current which in turn increases energy losses. In medium voltage and high-frequency cables reactance is the key factor influencing the voltage drop. CTS, by reducing impedance, delivers power more efficiently.
Voltage Drop
Voltage drop between the generation and load is a limiting factor for how long the cable line can be. With reduced voltage, a given load will draw greater current which in turn increases energy losses. In medium voltage and high-frequency cables reactance is the key factor influencing the voltage drop. CTS, by reducing impedance, delivers power more efficiently.
Losses and Skin Effect
Losses, mostly through heating, increase with resistance and frequency due to skin effect. Innovative cable design with CTS allows for more evenly distributed current across the cable core, leading to increased area conducting current and further reducing energy losses.
Losses and Reactance
Losses, mostly through heating, increase with resistance and frequency due to skin effect. Innovative cable design with CTS allows for more evenly distributed current across the cable core, leading to increased area conducting current and further reducing energy losses.
CTS and Capacitance
Typically, when dealing with cables, capacitance is to be avoided, so why is CTS adding it? The capacitance referred to in cable specifications is the capacitance between the core and the earth shield outside the cable’s insulation. This capacitance leads to current leaking to earth and is detrimental to performance. The longer the cable the worse this “shunt” capacitance problem becomes. CTS capacitance is inside the core and rather than leaking current, it is the means by which the current is delivered to the load, so the longer the cable the higher the capacitance of a CTS cable and the more “series capacitance” it can supply.
CTS and Capacitance
Typically, when dealing with cables, capacitance is to be avoided, so why is CTS adding it? The capacitance referred to in cable specifications is the capacitance between the core and the earth shield outside the cable’s insulation. This capacitance leads to current leaking to earth and is detrimental to performance. The longer the cable the worse this “shunt” capacitance problem becomes. CTS capacitance is inside the core and rather than leaking current, it is the means by which the current is delivered to the load, so the longer the cable the higher the capacitance of a CTS cable and the more “series capacitance” it can supply.
Advantages of CTS
The CTS cable design counteracts the inductive reactance generated by current flow, reducing total cable impedance and thus voltage drop. This significantly expands the range where a conventional cable has reached its limit and reduces energy losses.
In addition to reducing energy losses, our CTS enabled solutions have numerous advantages. This includes minimising capital costs, reducing maintenance requirements, saving raw materials and preserving natural beauty.
Lower power delivery losses
Innovative cable design provides up to 47% reduction in losses allowing more power to be delivered from sustainable generation
Lower capital costs
CTS cable solutions require smaller cable cross section or operate at a lower voltage level to deliver the same power as existing cables
Lower ongoing operating costs
Reduced number of system components lead to lower maintenance requirements or operation at lower voltage with less technically complex solutions
Higher availability
CTS-enabled high frequency power system solutions allow for flexible topologies and diverse operating regimes
Expandability
CTS cable opens opportunities to develop power systems that allow for easy-to-expand and modular solutions, accelerating implementation of low carbon technologies