Voltage equalizer apparatus and method thereof

A voltage equalizer comprising:

• a plurality of first windings electromagnetically coupled to each other;
• a plurality of storage elements series-connected to each other;
• a plurality of first switching elements, each connected to one of the first windings and one of the storage elements to constitute a closed circuit;
• a second winding electromagnetically coupled to the first windings;
• a second switching element series-connected to the second winding;
• a DC power supply series-connected to the second winding and the second switching element, the DC power supply for applying reference voltage to the second winding;
• a monitoring storage element connected between the second winding and the second switching element;
• and
• a third switching element connected between the DC power supply and the monitoring storage element,
• wherein all of the first switching elements and the second switching element are turned ON/OFF in synchronous;
• and
• the third switching element is turned OFF when voltage between terminals of the monitoring storage element is monitored.

A voltage equalizer comprising:

• a plurality of first windings electromagnetically coupled to each other;
• a plurality of storage elements series-connected to each other;
• a plurality of first switching elements, each connected to one of the first windings and one of the storage elements to constitute a closed circuit;
• a second winding electromagnetically coupled to the first windings;
• a second switching element series-connected to the second winding;
• a DC power supply series-connected to the second winding and the second switching element, the DC power supply for applying reference voltage to the second winding;
• a monitoring storage element connected between the second winding and the second switching element;
• and
• a diode biased along a forward direction to supply a current to the second winding if the voltage of the DC power supply is higher than a voltage between terminals of the monitoring storage element;
• wherein all of the first switching elements and the second switching element are turned ON/OFF in synchronous.

A voltage equalizer comprising:

• a plurality of first windings electromagnetically coupled to each other;
• a plurality of storage elements series-connected to each other;
• a plurality of first switching elements, each connected to one of the first windings and one of the storage elements to constitute a closed circuit;
• a second winding electromagnetically coupled to the first windings;
• a second switching element series-connected to the second winding;
• a DC power supply series-connected to the second winding and the second switching element, the DC power supply for applying reference voltage to the second winding;
• and
• a controller for turning ON/OFF all of the first switching elements and the second switching element in synchronous.

A voltage equalizing method for a voltage equalizer including a plurality of first windings electromagnetically coupled to each other;

• a plurality of storage elements series-connected to each other;
• a plurality of first switching elements, each connected to one of the first windings and one of the storage elements to constitute a closed circuit;
• a second winding electromagnetically coupled to the first windings;
• a second switching element series-connected to the second winding;
• a DC power supply series-connected to the second winding and the second switching element, the DC power supply for applying reference voltage to the second winding;
• a monitoring storage element connected between the second winding and the second switching element;
• and a third switching element connected between the DC power supply and the monitoring storage element, wherein all of the first switching elements and the second switching element are turned ON/OFF in synchronous;
• and the third switching element is turned OFF when voltage between terminals of the monitoring storage element is monitored,
• the voltage equalizing method comprising:
• charging the plurality of storage elements rapidly up to a predetermined charge voltage by a charging operation of an external power supply when a voltage between terminals of the storage elements is different from a target value by a predetermined voltage, or a higher voltage thereof;
• and
• turning both the first switching elements and the second switching element ON/OFF to control a terminal-to-terminal voltage of the storage elements to be equal to the target value.

A voltage equalizing method for a voltage equalizer including a plurality of first windings electromagnetically coupled to each other;

• a plurality of storage elements series-connected to each other;
• a plurality of first switching elements, each connected to one of the first windings and one of the storage elements to constitute a closed circuit;
• a second winding electromagnetically coupled to the first windings;
• a second switching element series-connected to the second winding;
• a DC power supply series-connected to the second winding and the second switching element, the DC power supply for applying reference voltage to the second winding;
• a monitoring storage element connected between the second winding and the second switching element;
• and
• a third switching element connected between the DC power supply and the monitoring storage element, wherein all of the first switching elements and the second switching element are turned ON/OFF in synchronous;
• and
• the third switching element is turned OFF when voltage between terminals of the monitoring storage element is monitored,
• the voltage equalizing method comprising:
• setting the voltage of the DC power supply to a voltage on the side of the target value and in the vicinity of a voltage of the monitoring storage element when a voltage between terminals of the storage element becomes a value different from a target value by a predetermined voltage, or a higher voltage thereof,;
• and
• turning both the first switching elements and the second switching element ON/OFF;
• and
• carrying out a control operation to gradually approximate the voltage of the DC power supply to the target value.