Controlling voltage in electrical power distribution grid

A system for controlling grid voltage in a power grid, the system comprising:

• a power transformer with primary leads and secondary leads, wherein the power transformer is configured to convert alternating current (AC) electrical power at a higher voltage on the primary leads to AC electrical power at a lower grid voltage on the secondary leads;
• a first auxiliary AC/AC power converter with first input conductors and first output conductors, wherein the first auxiliary AC/AC power converter is configured to convert input AC electrical power at the first input conductors to output AC electrical power at the first output conductors, wherein the first auxiliary AC/AC power converter is configured to convert substantially less electrical power than the AC electrical power converted by the power transformer;
• wherein the secondary leads of the power transformer are series-connected to the first output conductors of the first auxiliary AC/AC power converter;
• wherein the first input conductors of the first auxiliary AC/AC power converter are parallel-connected to the primary leads of the power transformer;
• wherein the output alternating voltage of the first auxiliary AC/AC power converter adds to the output alternating voltage of the power transformer to control the grid voltage in the power grid.

A system for controlling grid voltage in a power grid, the system comprising:

• a power line with input leads and output leads, wherein the power line carries alternating current (AC) electrical power between the input and output leads;
• an auxiliary AC/AC power converter with input conductors and output conductors, wherein the auxiliary AC/AC power converter is configured to convert input AC electrical power at the input conductors to output AC electrical power at the output conductors, wherein the auxiliary AC/AC power converter is configured to convert substantially less electrical power than the AC electrical power carried by the power line;
• wherein the output leads of the power line are series-connected to the output conductors of the auxiliary AC/AC power converter;
• wherein the input conductors of the auxiliary AC/AC power converter are parallel-connected to the input leads of the power line;
• wherein the output alternating voltage of the auxiliary AC/AC power converter adds to the output alternating voltage of the power line to control the grid voltage in the power grid.