* Cuts operating f'cast to 180 bln yen from 220 bln yen

* Q3 operating profit up 91% y/y at 53 bln yen

TOKYO, Jan 24 (Reuters) - Japanese electric motor maker Nidec Corp slashed its full-year operating profit forecast by nearly a fifth on Wednesday, warning of uncertainty in demand and intensifying price competition in China's electric vehicle market.

The sobering outlook for the company's signature e-axle traction motor business highlights the challenges parts makers face in the world's biggest auto market, a price war and fewer subsidies for EV buyers has increased pressures to cut costs.

The Kyoto-based manufacturer cut its operating profit forecast for the financial year to March 31 by 18% to 180 billion yen ($1.22 billion), versus an average forecast of 219.7 billion yen by 18 analysts surveyed by LSEG.

Kazuyoshi Saito, a senior analyst at Iwai Cosmo Securities, said the filings suggested it may take longer than expected for Nidec to revitalise the e-axle traction motor business, adding the company is known for its heavy dependence on China.

The company has invested heavily in developing and producing the motor, which combines an EV's gear, motor and power-control electronics, and is keen to expand the business.

"It feels like it won't be able to survive unless they implement a major change in strategy," Saito said, commenting on the traction motor business in China. "I'm concerned it will be a negative surprise for the stock price."

Third-quarter operating profit nearly doubled to 53.6 billion yen, compared to 28.0 billion yen a year earlier. That was slightly lower than a 55.6 billion yen average profit in a survey of eight analysts by LSEG.

Nidec said in presentation materials it expected to book expenses for structural reforms of its EV-traction business before improving the segment's profitability, without adding exact details of the measures it plans to take.

The company is set to hold a briefing about the results at 0800 GMT on Wednesday, where its billionaire founder Shigenobu Nagamori will address journalists and analysts.

It aims to improve its EV-traction business in China through limiting unprofitable orders and localising product development and procurement, it said in the presentation materials. ($1 = 147.9500 yen) (Reporting by Daniel Leussink; Editing by Tom Hogue and Kim Coghill and Miral Fahmy)