Abstract: A tokamak plasma vessel. The tokamak plasma vessel comprises a toroidal plasma chamber, a plurality of poloidal field coils, an upper divertor assembly, and a lower divertor assembly. The plurality of poloidal field coils are configured to provide a poloidal magnetic field having a substantially symmetric plasma core and an upper and lower null, such that ions in a scrape off layer outside the plasma core are directed by the magnetic field past one of the upper and lower nulls to divertor surfaces of the respective upper and lower divertor assembly. Each of the upper and lower divertor assembly comprises a liquid metal inlet and a liquid metal outlet located below the liquid metal inlet. Each of the upper and lower divertor assembly is configured such that in use liquid metal flows from the liquid metal inlet to the liquid metal outlet over at least one divertor surface of the divertor assembly.

Abstract: A method of controlling a plasma in a nuclear fusion reactor. The nuclear fusion reactor comprises sensors and plasma control inputs. An initial control model is provided, relating readings of at least a subset of the sensors to control of the plasma control inputs. A control loop is performed, comprising: operating the plasma control inputs in dependence upon the sensors according to the control model; determining correlations between readings of each of the sensors, and/or between readings of the sensors and states of the plasma control inputs; and adjusting the control model based on the determined correlations.

Abstract: A method of controlling a plasma in a nuclear fusion reactor. The nuclear fusion reactor comprises sensors and plasma control inputs. An initial control model is provided, relating readings of at least a subset of the sensors to control of the plasma control inputs. A control loop is performed, comprising: operating the plasma control inputs in dependence upon the sensors according to the control model; determining correlations between readings of each of the sensors, and/or between readings of the sensors and states of the plasma control inputs; and adjusting the control model based on the determined correlations.

Abstract: A method of controlling a plasma in a nuclear fusion reactor. The nuclear fusion reactor comprises sensors and plasma control inputs. An initial control model is provided, relating readings of at least a subset of the sensors to control of the plasma control inputs. A control loop is performed, comprising: operating the plasma control inputs in dependence upon the sensors according to the control model; determining correlations between readings of each of the sensors, and/or between readings of the sensors and states of the plasma control inputs; and adjusting the control model based on the determined correlations.

Abstract: A tokamak comprising a vacuum chamber, a toroidal field coil, and a solenoid. The solenoid is wound around the toroidal field coil within a central column region of the tokamak. The solenoid comprises an inner portion and two outer portions. The inner portion comprises windings extending axially for a first distance either side of the midpoint of the length of the solenoid. The outer portions, each comprise windings extending axially from an end of the inner portion. The inner portion has a number of turns per unit length which is greater than a number of turns per unit length of the outer portion.

Abstract: A tokamak plasma vessel. The tokamak plasma vessel comprises a toroidal plasma chamber, a plurality of poloidal field coils, an upper divertor assembly, and a lower divertor assembly. The plurality of poloidal field coils are configured to provide a poloidal magnetic field having a substantially symmetric plasma core and an upper and lower null, such that ions in a scrape off layer outside the plasma core are directed by the magnetic field past one of the upper and lower nulls to divertor surfaces of the respective upper and lower divertor assembly. Each of the upper and lower divertor assembly comprises a liquid metal inlet and a liquid metal outlet located below the liquid metal inlet. Each of the upper and lower divertor assembly is configured such that in use liquid metal flows from the liquid metal inlet to the liquid metal outlet over at least one divertor surface of the divertor assembly.

Abstract: A poloidal field coil assembly for use in a tokamak. The poloidal field coil assembly comprises inner and outer poloidal field coils and a controller. The inner poloidal field coil is configured for installation inside a toroidal field coil of the tokamak. The outer poloidal field coil is configured for installation outside the toroidal field coil. The controller is configured to cause current to be supplied to the inner and outer poloidal field coils such that the combined magnetic field produced by the inner and outer poloidal field coils has a null at the toroidal field coil.

Abstract: A tokamak plasma vessel. The tokamak plasma vessel comprises a toroidal plasma chamber, a plurality of poloidal field coils, an upper divertor assembly, and a lower divertor assembly. The plurality of poloidal field coils are configured to provide a poloidal magnetic field having a substantially symmetric plasma core and an upper and lower null, such that ions in a scrape off lay outside the plasma core are directed by the magnetic field past one of the upper and lower nulls to divertor surfaces of the respective upper and lower divertor assembly. Each of the upper and lower divertor assembly comprises a liquid metal inlet and a liquid metal outlet located below the liquid metal inlet. Each of the upper and lower divertor assembly is configured such that in use liquid metal flows from the liquid metal inlet to the liquid metal outlet over at least one divertor surface of the divertor assembly.

Abstract: A tokamak plasma vessel. The tokamak plasma vessel comprises a toroidal plasma chamber, a plurality of poloidal field coils, an upper divertor assembly, and a lower divertor assembly. The plurality of poloidal field coils are configured to provide a poloidal magnetic field having a substantially symmetric plasma core and an upper and lower null, such that ions in a scrape off lay outside the plasma core are directed by the magnetic field past one of the upper and lower nulls to divertor surfaces of the respective upper and lower divertor assembly. Each of the upper and lower divertor assembly comprises a liquid metal inlet and a liquid metal outlet located below the liquid metal inlet. Each of the upper and lower divertor assembly is configured such that in use liquid metal flows from the liquid metal inlet to the liquid metal outlet over at least one divertor surface of the divertor assembly.

Abstract: A poloidal field coil assembly for use in a tokamak. The poloidal field coil assembly comprises inner and outer poloidal field coils and a controller. The inner poloidal field coil is configured for installation inside a toroidal field coil of the tokamak. The outer poloidal field coil is configured for installation outside the toroidal field coil. The controller is configured to cause current to be supplied to the inner and outer poloidal field coils such that the combined magnetic field produced by the inner and outer poloidal field coils has a null at the toroidal field coil.

Abstract: A method of controlling a plasma in a nuclear fusion reactor. The nuclear fusion reactor comprises sensors and plasma control inputs. An initial control model is provided, relating readings of at least a subset of the sensors to control of the plasma control inputs. A control loop is performed, comprising: operating the plasma control inputs in dependence upon the sensors according to the control model; determining correlations between readings of each of the sensors, and/or between readings of the sensors and states of the plasma control inputs; and adjusting the control model based on the determined correlations.