Quebec – New England Transmission

The HVDC Quebec - New England is a high-voltage direct current transmission line from Radisson, Quebec to Sandy Pond in Ayer, Massachusetts. In contrast to most other HVDC plants, it is a multi-point connection. Originally it consisted of the 172 km section between Des Cantons and Comerford Reservoir in Quebec, New Hampshire, which had to be performed because of the asynchronous operation of both power grids as HVDC. This line went into operation in 1986 and was able to transfer a maximum power of 690 MW. The bipolar operation voltage is ± 450 kV.

It was planned to extend the line through the endpoints in Des Cantons and Comerford addition to transfer power from the hydroelectric power plants at La Grande in the Baie- James region in the Boston area. For this reason, the line was extended to 1100 km north to the Radisson converter station and south to the converter station Sandy Pond in Massachusetts. The transmission power was increased in this case by expanding the converter stations 2 GW. The operating voltage was unchanged at ± 450 kV. For the connection of the area around Montreal was built in the year 1992, another converter station at Nicolet with a transmission capacity of 2 GW.

Crossing the St. Lawrence River

The crossing of the St. Lawrence River is remarkable since it was first performed as an overhead line crossing, and later replaced by a cable tunnel. This unusual procedure system has been used, because only with an overhead power line crossing a timely commissioning was possible, but it was feared the lack of acceptance of the overhead line crossing in the population of Grondines and Lotbinière.

In 1988, construction work on three artificial islands in the St. Lawrence River, which were provided with dams to the mainland, as a building site for the masts of the overhead line crossing. This 20,000 truck loads were transported a total of 400,000 tons between July 1988 and spring 1989. 1989 erected the five masts of the overhead line crossing, which took a total of five months. The two pylons on each side of the fairway were 140 m high, to ensure the required headroom. The erection of these masts took five months. The end of 1989 the overhead line crossing was completed.

In the spring of 1989, the work for the 3954 -meter-long cable tunnel began. The average rate of penetration was 27 m per day. On March 26, 1990, the tunnel boring machine reached the surface, 8 cm away from its target point. Later, the tunnel has been covered with concrete and grooves mounted on the cord. On 1 November 1990, the line went with a transmission capacity of 1.2 GW in operation, which was increased on July 1, 1991 to 2.25 GW. 1992 dismantled to the overhead line crossing, including the dams and man-made islands. One of the masts was to build up the observation tower of the Cite de l' uses energy. The cost of the reduction amounted to 16 million Canadian dollars.

Coordinates

  • Endpoint Radisson, Quebec: 53 ° 43 '30 " N, 77 ° 44' 13" W53.725 - 77.736944444444
  • Northern end of the cable tunnel under the St. Lawrence River: 46 ° 37 '32 "N, 72 ° 0' 51" W46.625555555556 - 72.014166666667
  • Endpoint Sandy Pond in Ayer, Massachusetts: 42 ° 34 ' 13 " N, 71 ° 31' 27" W42.570277777778 - 71.524166666667
  • Reusing one of the pylons as a lookout at a theme park in Shawinigan, Quebec 46 ° 32 ' 11.9 "N, 72 ° 45' 28.1 " W46.536652 - 72.757816
Deschambault-Grondines
390799
de