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Rare earth mines in Ganzhou, China to halt production by end of year

Xinhua. Eastern Ganzhou city has ordered three rare earth mines to halt production by year-end, according to local mining authorities.

The city issued a notice telling three of its eight major rare earth producing counties to halt production by the end of this year, said Li Guoqing, director of the city’s mining management bureau, on Monday. The three counties are mining areas that are allowed to be exploited, Li said.

...It is unknown when production will resume, as they have to wait for directives from the provincial government, Li said. The notice also told the counties to set production quotas to rare earth mines to prevent over-exploitation.

Ganzhou, Jiangxi Province, produces nearly 40% of China’s ionic rare earths, while China produces more than 90% of the world’s rare earth metals. China’s rare earth reserves only account for about one third of the world’s total, Xinhua notes, adding that to control environmental damage and protect resources, China has announced various policies, such as suspending the issuance of new licenses for rare earth prospecting and mining, imposing production caps and export quotas, and implementing tougher environmental standards.


Henry Gibson

Switched Reluctance motors are lighter weight and less costly to build and require no permanent magnets.

In the US there is a massive deposit of thorium and rare earths at the very spot where the explorers Lewis and Clark first looked over the continental watershed divide, from present Montana into Idaho at Lemhi pass.

Modern electronics allow the use of the complicated switching required for the less costly and redundantly reliable reluctance drives that are not damaged as easily by over heating. ..HG..


Thanks Henry. I've never taken the time to read up on the SR motors before and it looks very promising.

I read everything I could find and the only place they seem to lag a bit is on low-end torque compared to PM motors and with the new 2-3 speed transmissions coming out for EVs, that would not be a factor anyway.


HG, what do you know of SepEx motors?


Switched or variable reluctance motors have been around in limited numbers since 1969. There are many reasons why they are not mass produced nor (yet) used for electrified vehicles.

They have many advantages such as: (1) simplicity and lower construction cost (2) no permanent magnets, no rare earth required (3) high starting torque depending or number of poles and control unit design. (4) high ambient temp capabilities.

Their inherent disadvantages have not all been fully addressed, the main remaining one are: (1) current versus torque is highly non-linear (a multi-speed transmission would help (needed) to keep it in the sweet spot) (2) Phase and current switching must be very precise to reduce torque ripple (recent high speed high power solid states controllers can address that) (3) High acoustical and electrical noise (can be reduce with improved design and multi-poles)(4) Complex/costly control issues (mass production could partially address this problem)

The scarcity of rare earth and the availability of lower cost control units may promote future use of those simple motors.


The availability of substitutes is one of the great unreported stories of this affair. Induction motors are also quite suitable for EVs and even hybrids; GM's BAS II uses an induction motor/generator, and the EV1 used twin induction motors. No REEs required in either.


Yes E-P..recent dual induction motors design are competitive and good potential candidates for electrified vehicles. Electronics may be harder hit, at least until such times as we learn to do without REEs.

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