Phase change assisted heat sink

• US 6,417,577 B1
• Filed: 03/29/2001
• Issued: 07/09/2002
• Est. Priority Date: 11/22/1999
• Status: Expired due to Fees

• Current Assignee: BAE Systems Controls Incorporated (BAE Systems Plc)
• Original Assignee: BAE Systems Controls Incorporated (BAE Systems Plc)
• Inventors: Osovski, Steve William, Grewe, Timothy Michael
• Primary Examiner(s): PONOMARENKO, NICHOLAS
• Application Number:
  US09/820,399
• Publication Number:
  US 20020024221A1
• Time in Patent Office: 467 Days
• Field of Search: 290/40.C, 290/40.B, 322/16, 318/362, 180/65.2, 180/65.4, 123/41.13, 123/41.14
• US Class Current: 290/40.00C
• CPC Class Codes: B60K 11/00 Arrangement in connection with cooling of propulsion units heating the interior space B60H; cooling internal combustion engines per se F01P
• CPC Class Codes: B60K 2001/003 with means for cooling the electrical propulsion units
• CPC Class Codes: B60K 6/46 Series type
• CPC Class Codes: B60L 2270/44 Heat storages, e.g. for cabin heating
• CPC Class Codes: B60L 50/15 with additional electric power supply with capacitors charged by engine-driven generators B60L50/40; with batteries charged by engine-driven generators B60L50/61
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/15 Control strategies specially adapted for achieving a particular effect
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: F01P 1/06 Arrangements for cooling other engine or machine parts
• CPC Class Codes: F01P 2003/2278 Heat pipes
• CPC Class Codes: F01P 2050/24 Hybrid vehicles
• CPC Class Codes: F01P 2050/30 Circuit boards
• CPC Class Codes: H02K 2209/00 Specific aspects not provided for in the other groups of this subclass relating to systems for cooling or ventilating
• CPC Class Codes: H02K 7/006 Structural association of a motor or generator with the drive train of a motor vehicle
• CPC Class Codes: H02K 9/00 Arrangements for cooling or ventilating channels or ducts in parts of the magnetic circuit H02K1/20, H02K1/32; channels or ducts in or between conductors H02K3/22, H02K3/24
• CPC Class Codes: H02K 9/22 by solid heat conducting material embedded in, or arranged in contact with, the stator or rotor, e.g. heat bridges
• CPC Class Codes: H05K 7/20 Modifications to facilitate cooling, ventilating, or heating
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors

Abstract

In an electric vehicle, the traction motor is driven from a battery by way of a controllable electric power switcher. In operation of the switcher, the power losses of the switches depends upon the power being handled; during acceleration the power is high, and at constant speed on level ground the power is small. Thus, the power “dissipated” by the switches varies with time. A cooler transfers heat from the switcher. During acceleration, the cooler may not be sufficient to limit the instantaneous switch temperature. A phase-change heat “sink” coupled to the switches absorbs heat from the switches during hard acceleration, and returns the heat to the cooler under more constant-speed conditions.

Claims

1. A vehicle including

an electric traction drive machine;

a source of electrical energy;

a controllable switching arrangement coupled to said traction drive machine and to said source of electrical energy, for coupling energy between said source of electrical energy and said motor under the control of control signals;

operator-controlled control means coupled to said switching arrangement, for controlling the amount of energy coupled between said source and said machine by synthesizing a current waveform;

a cooling system coupled to said controllable switching arrangement, for transferring heat from said switching arrangement to ambient; and

a phase change energy transducer coupled to said cooling system and to said switching arrangement, for transiently absorbing heat generated by said switching arrangement in excess of that which said cooling system can instantaneously transfer.

2. An apparatus, comprising:

an electrical machine [drive motor];

a source of electrical energy;

controllable switching means coupled to said machine [motor] and to said source of electrical energy, for providing energy to said machine [motor] from said source in an amount which varies with time, whereby the energy handled by said switching means varies with time, and the power-loss-generated heat in said switching means also varies with time;

cooling means coupled to said switching means, for transferring said heat from said switching means to ambient, whereby the instantaneous temperature of said switching means tends to vary in response to the power being handled by said switching means; and

phase change energy transducing means thermally coupled to said switching means and to said cooling means, for absorbing heat from said switching means when said instantaneous temperature of said switching means tends to rise, and for releasing heat to said cooling means when said instantaneous temperature of said switching means tends to fall, thereby tending to maintain said temperature of said switching means constant.

3. a vehicle, comprising:

a drive wheel;

a generator coupled to said wheel for generating electrical energy in response to braking;

an electrical resistor coupled to said generator, for converting the electrical energy of braking into heat; and

a phase change transducer thermally coupled to said resistor, for storing heat from resistor.

4. A vehicle according to claim 3, further comprising:

a cooling system for cooling said resistor, said cooling system being dimensioned to accommodate an average heat generated by said resistor;

whereby said phase change transducer stores heat during those times in which the heat generated by said resistor exceeds the steady-state cooling capacity of said cooling system.

5. An apparatus, comprising:

a drive motor;

a source of electrical energy;

controllable switching means coupled to said motor and to said source of electrical energy, for providing energy to said motor from said source in an amount which varies with time, whereby the energy handled by said switching means varies with time, and the power losses in said switching means also varies with time;

cooling means coupled to said switching means, for transferring heat from said switching means to ambient, whereby the temperature of said switching means may vary depending upon the instantaneous power being handled; and

phase change energy transducing means coupled to said switching means and to said cooling means, for temporarily changing phase and tending to maintain said temperature of said switching means constant.