The longer you live in Japan the more likely it is that Japanese style rice will become an important part of your diet and something you enjoy. What to do when you want to duplicate that experience outside Japan?
Buy a Japanese Model
One option is to buy a Japanese rice cooker of your choice and then buy a step-down transformer to Japan’s unusual 100V power system. On the plus side this means you can buy any rice cooker you desire, including the newest models with features that export models may never see.
The downside however is that you must also buy a step-down transformer. Rice cookers draw a lot of power, typically over 1200W and the new IH + pressure cooking Zojirushi NW-AT10 draws 1450W. Worse, rice cookers run for extended periods of time which means the transformer must be able to provide stable, clean power for extended periods. In order to safely do this you must choose a transformer with a power rating at least 20% higher than your rice cooker’s power requirements. If the transformer fails your rice cooker will die an immediate death, and not necessarily in a safe & controlled way. (In other words, cheaping out on the transformer might result in burning down your house!)
If you are going to a country with 220V to 240V power then this Kashimura NTI-20 transformer should safely power a ~1200W rice cooker. However if you are looking at a rice cooker that draws more than 1250W you should purchase a larger transformer such as the Kashimura NTI-151.
For those who are going to North America or elsewhere with 110V to 130V power the Kashimura NTI-149 would be suitable for a typical ~1200W rice cooker and the NTI-150 for more power hungry models that exceed 1250W.
You will see smaller & cheaper units advertised with “optimistic” (i.e. unrealistic!) maximum power ratings. It is not safe to use such compact transformers for a product like a rice cooker that draws a lot of power for an extended period of time. As mentioned above, cheaping out on the transformer may result in burning down your house. Please choose the transformer you purchase carefully.
Finally, it’s important to note that transformers must be kept dry, and they generate heat while in use. Really, using a transformer in your kitchen is not an ideal thing to do. For maximum safety you need to run the transformer and rice cooker away from anywhere a splash of liquid is likely to reach.
Buy an Export Model
The cheaper & safer option is to purchase a rice cooker designed for use outside Japan. These devices will already have power supplies that are suitable for ~115V or ~230V power systems and therefore do not require the use of a transformer.
The recent boom in visitors from China has resulted in many more 220V rice cookers available, including very recent models. The Zojirushi NP-HLH10 was released last year and has features similar to Zojirushi’s top Japanese Domestic Market (JDM) models. The big Japanese makers are all competing for purchases from Chinese visitors so it’s reasonable to expect the regular release of 220V models with market leading features.
Unfortunately the number of ~120V rice cooker options has not seen a similar increase, and the few that do exist do not have features comparable to the best JDM models. As of this writing in early 2018 the best option is actually available in the US from Amazon.com, the Tiger JKT-S10U. It has the features of Japanese rice cookers priced around 15,000yen, and these are the types of rice cookers used in many Japanese households.
Good luck, and happy eating!