Wireless power reception method of a wireless power receiver in which first demanded power of the wireless power receiver is adjusted within a first available power of the wireless power tansmitter

1. A method for transmitting wireless power by a wireless power transmitter, the method comprising:

performing an initiation process with a wireless power receiver, the initiation process comprising:

transmitting a connection signal to the wireless power receiver for detecting and identifying the wireless power receiver, and

in response to transmitting the connection signal, receiving a response signal from the wireless power receiver and identifying the wireless power receiver based on the response signal;

performing a negotiation process with the wireless power receiver for negotiating a power transmission condition, the negotiation process being performed in a specific order comprising:

receiving a request signal from the wireless power receiver to retrieve a capability of the wireless power transmitter, the capability including a first available amount of power of the wireless power transmitter,

transmitting the capability to the wireless power receiver, in response to the request signal, so that the wireless power receiver determines a demanded amount of power based on the first available amount of power, and

receiving the demanded amount of power to set up the power transmission condition from the wireless power receiver, the demanded amount of power being less than the first available amount of power of the wireless power transmitter;

transmitting first wireless power to the wireless power receiver based on the power transmission condition when the demanded amount of power is less than the first available amount of power and allowable by the wireless power transmitter based on the capability of the wireless power transmitter;

in response to a state of the wireless power transmitter changing to a reduced capability based on an external factor while conducting power transmission, stopping transmission of the first wireless power and directly re-entering the negotiation process with the wireless power receiver without re-entering the initiation process to generate an adjusted power transmission condition different than the power transmission condition; and

after the re-entering of the negotiation process, transmitting second wireless power to the wireless power receiver without re-entering the initiation process according to the adjusted power transmission condition, the second wireless power being different than the first wireless power.

2. The method of claim 1 , further comprising:

in response to a state of the wireless power receiver changing while conducting power transmission, re-entering the negotiation process with the wireless power receiver to adjust the power transmission condition.

3. The method of claim 1 , wherein the demanded amount of power of the wireless power receiver is within a range of the first available amount of power of the wireless power transmitter.

4. A method for receiving wireless power by a wireless power receiver, the method comprising:

performing an initiation process with a wireless power transmitter, the initiation process comprising:

receiving a connection signal from the wireless power transmitter for detecting and identifying the wireless power receiver, and

in response to receiving the connection signal, transmitting a response signal to the wireless power transmitter including information for identification of the wireless power receiver;

performing a negotiation process with the wireless power transmitter for negotiating a power transmission condition, the negotiation process being performing in a specific order comprising:

transmitting a request signal to the wireless power transmitter to retrieve a capability of the wireless power transmitter,

receiving the capability from the wireless power transmitter in response to the request signal, the capability including a first available amount of power of the wireless power transmitter,

determining a demanded amount of power that is less than the first available amount of power, and

transmitting the demanded amount of power to set up the power transmission condition to the wireless power transmitter;

receiving first wireless power from the wireless power transmitter based on the power transmission condition when the demanded amount of power is less than the first available amount of power and allowable by the wireless power transmitter based on the capability of the wireless power transmitter;

in response to a state of the wireless power transmitter changing to a reduced capability based on an external factor during power transmission, losing reception of the first wireless power and directly re-entering the negotiation process with the wireless power transmitter without re-entering the initiation process to generate an adjusted power transmission condition different than the power transmission condition; and

after the re-entering of the negotiation process, receiving second wireless power from the wireless power transmitter without re-entering the initiation process according to the adjusted power transmission condition, the second wireless power being different than the first wireless power.

5. The method of claim 4 , further comprising:

in response to a state of the wireless power receiver changing while conducting power transmission, re-entering the negotiation process with the wireless power transmitter to adjust the power transmission condition.

6. The method of claim 4 , wherein the demanded amount of power of the wireless power receiver is within a range of the first available amount of power of the wireless power transmitter.

7. A wireless power receiver for receiving wireless power, the wireless power receiver comprising

a controller configured to:

perform an initiation process with a wireless power transmitter, the initiation process comprising:

receiving a connection signal from the wireless power transmitter for detecting and identifying the wireless power receiver, and

in response to receiving the connection signal, transmitting a response signal to the wireless power transmitter including information for identification of the wireless power receiver;

perform a negotiation process with the wireless power transmitter for negotiating a power transmission condition, the negotiation process being performed in a specific order comprising:

transmitting a request signal to the wireless power transmitter to retrieve a capability of the wireless power transmitter,

receiving the capability from the wireless power transmitter in response to the request signal, the capability including a first available amount of power of the wireless power transmitter,

determining a demanded amount of power that is less than the first available amount of power, and

transmitting the demanded amount of power to set up the power transmission condition to the wireless power transmitter;

a coil configured to receive first wireless power from the wireless power transmitter based on the power transmission condition when the demanded amount of power is less than the first available amount of power and allowable by the wireless power transmitter based on the capability of the wireless power transmitter; and

a rectifier configured to transfer DC power to a load by converting the wireless power received from the wireless power transmitter,

wherein the controller is further configured to:

in response to a state of the wireless power transmitter changing to a reduced capability based on an external factor during power transmission, directly re-enter the negotiation process with the wireless power transmitter without re-entering the initiation process to generate an adjusted power transmission condition different than the power transmission condition, and

wherein the coil is further configured to after the re-entering of the negotiation process, receive second wireless power from the wireless power transmitter without re-entering the initiation process according to the adjusted power transmission condition, the second wireless power being different than the first wireless power.

8. The wireless power receiver of claim 7 , wherein the controller is further configured to:

in response to a state of the wireless power receiver changing while conducting power transmission, re-enter the negotiation process with the wireless power transmitter to adjust the power transmission condition.

9. The wireless power receiver of claim 7 , wherein the demanded amount of power of the wireless power receiver is within a range of the first available amount of power of the wireless power transmitter.