POWER CONTROL SYSTEM

• US 3,686,549 A
• Filed: 02/01/1971
• Issued: 08/22/1972
• Est. Priority Date: 02/01/1971
• Status: Expired due to Term

• Current Assignee: Gary L. Winebrener
• Original Assignee: Gary L. Winebrener
• Inventors: Winebrener, Gary L.
• Primary Examiner(s): Simmons, G. R.
• Application Number:
  US05/111,181
• Time in Patent Office: 568 Days
• Field of Search: 318/139,440,341 307/80,81 180/60 290/38,50
• US Class Current: 318/139
• CPC Class Codes: H02P 7/29 using pulse modulation

Abstract

A primary battery or energy battery and a secondary battery or power battery are connected through a pair of synchronized pulse modulators with a drive motor in the vehicle electric drive power supply system of this invention. The energy battery alone supplies power to the drive motor when power, voltage, current, and speed parameters of the electric drive are each within a first predetermined range of values. If one or more of the measured parameters is within a second predetermined range of values, power from the power battery complements power from the energy battery to supply the motor. According to the invention, when the two batteries are jointly supplying the motor, each battery is sequentially and periodically connected with the motor through its respective pulse modulator such that each battery has a variable duty cycle; however, conduction by the batteries is complementary in time within each cycle of the pulse modulators and simultaneous connection of both batteries with the motor is precluded.

Claims

1. A power supply for supplying an electric drive motor in a vehicle electric drive comprising:

a primary source of direct voltage, a secondary source of direct voltage, a first energizing circuit path including a first semiconductor controllable switching device interconnecting said electric drive motor and said primary source of direct voltage, said first semiconductor controllable switching device affording control of the connection of said electric drive motor and said primary source of direct voltage including control of the time of initiation and the time of termination of current flow therebetween, a second energizing circuit path including a second semiconductor controllable switching device and excluding both said primary source of direct voltage and said first semicondUctor controllable switching device for interconnecting said electric drive motor and said secondary source of direct voltage, said second semiconductor controllable switching device affording control of the connection of said electric drive motor and said secondary source of direct voltage including control of the time of initiation and the time of termination of current flow therebetween, and a control means coupled to said first and second semiconductor switches for controlling the switching of said first semiconductor switch while preventing conduction of said second semiconductor switch during a first mode of operation whereby said motor is supplied solely by said primary battery during said first mode of operation, said control means including means responsive to a predetermined electrical loading condition of said primary source of direct voltage of said vehicle drive system for causing said semiconductor switches to operate in a second mode of operation, said control means during said second mode of operation sequentially rendering said first and second semiconductor controllable switching devices alternately and consecutively conductive to provide power from both said primary and secondary sources of direct voltage when said loading condition is attained, said control means including means for varying the duty cycle of each of said controllable switching devices in response to an operating condition of said system whereby each source supplies a predetermined portion of the power required to operate said electric drive motor during said second mode of operation.

2. A dual battery power supply for an electric drive vehicle comprising:

an electric drive motor, an energy battery, a power battery, a first pulse modulator including a first controlled rectifier, a first circuit path including said first pulse modulator interconnecting said electric drive motor and said energy battery, said first controlled rectifier affording control of the connection of said electric drive motor and said energy battery including control of the time of initiation and the time of termination of current flow therebetween, a second pulse modulator including a second controlled rectifier, a second circuit path including said second pulse modulator and excluding both said energy battery and said first pulse modulator for interconnecting said electric drive motor and said power battery, said second controlled rectifier affording control of the connection between said electric drive motor and said power battery including control of the time of initiation and the time of termination of current flow therebetween, and a control means coupled to said first and second controlled rectifiers for controlling the switching of said first controlled rectifier while preventing conduction of said second controlled rectifier during a first mode of operation whereby said motor is supplied solely by said energy battery during said first mode of operation, said control means including means responsive to a predetermined electrical loading condition of said energy battery for sequentially rendering said first controlled rectifier and said second controlled rectifier alternately and consecutively conductive to provide power from both said energy battery and said power battery to said electric drive motor when said electrical loading condition attains said predetermined value and during a second mode of operation, said control means effecting control of said batteries such that each of said batteries has a variable duty cycle and provides a controllable portion of the power required to operate said electric drive motor during said second mode of operation.

3. A power control system for a vehicle electric drive comprising:

an electric drive motor, a primary direct voltage source, a secondary direct voltage source, a first circuit path including a first controllable switching device interconnecting said electric drive motor and said primary direct voltage source, said first controllable switching device affording control of tHe connection of said electric drive motor and said primary direct voltage source including control of the time of initiation and the time of termination of current flow therebetween, a second circuit path including a second controllable switching device and excluding both said primary direct voltage source and said first controllable switching device interconnecting said electric drive motor and said secondary direct voltage source, said second controllable switching device affording control of the connection of said electric drive motor and said secondary direct voltage source including control of the time of initiation and the time of termination of current flow therebetween, and a control means connected with both said first controllable switching device and said second controllable switching device to control the power from said first and second direct voltage sources to said electric drive motor, said control means including means sensing at least one vehicle operating parameter, said control means causing distinct modes of operation by said power control system according to the instantaneous values of the sensed vehicle operating parameter, said control means causing said primary direct voltage source to be the exclusive supply for said electric drive motor when said sensed vehicle operating parameter is within a first predetermined range of values, said control means causing said switching devices to become alternately and consecutively conductive whereby said primary and secondary direct voltage sources alternately supply said electric drive motor when said sensed vehicle operating parameter is within a second predetermined range of values, said control means effecting control of said primary direct voltage source and said secondary direct voltage source such that each source has a variable duty cycle and such that each source provides a portion of the power required to operate said electric drive motor when said sensed vehicle operating parameter is within said second predetermined range of values.

4. A dual battery power supply for an electric drive vehicle comprising:

an electric drive motor, an energy battery, a power battery, a first pulse modulator including a first semiconductor controllable switching device, a first circuit path including said first pulse modulator interconnecting said electric drive motor and said energy battery, said first semiconductor controllable switching device affording control of the connection of said electric drive motor and said energy battery including control of the time of initiation and the time of termination of current flow therebetween, a second pulse modulator including a second semiconductor controllable switching device, a second circuit path including said second pulse modulator and excluding both said energy battery and said first pulse modulator for interconnecting said electric drive motor and said power battery, said second semiconductor controllable switching device affording control of the connection between said electric drive motor and said power battery including control of the time of initiation and the time of termination of current flow therebetween, and a control source connected with both said first pulse modulator and said second pulse modulator to control the conduction of both said first semiconductor controllable switching device and said second semiconductor controllable switching device, said control source including means for sensing operating parameters of the electric drive, said control source effecting cyclic operation of said first and second pulse modulators, said control source causing said first semiconductor controllable switching device to conduct during each cycle and said second semiconductor controllable switching device to remain nonconductive throughout each cycle when said sensed parameters have values in a first predetermined range of values, said control source causing said first semiconductor controllable switching device to conduct during each cycle and said second semiconducTor controllable switching device to conduct each cycle during a time interval in which said first semiconductor controllable switching device is nonconductive when said sensed parameters have values in a second predetermined range of values, said energy battery exclusively supplying said electric drive motor when said sensed parameters are in said first predetermined range of values, said power battery augmenting the power from said energy battery to supply said electric drive motor from both batteries when said sensed parameters are in said second predetermined range of values.

5. A power supply for supplying electric power to an electric drive motor of an electrically propelled vehicle, comprising:

an electric motor for driving at least one wheel of said vehicle, a primary source of direct voltage, a secondary source of direct voltage, a first energizing circuit for said motor including a first switching means operable to connect and disconnect said primary source of direct voltage and said motor to thereby control the average voltage applied to said motor, a second energizing circuit for said motor including a second switching device for energizing said electric motor from said secondary source of direct voltage, a control means coupled to said first and second switching devices for controlling the switching operation of said first and second switching devices, said control means during a first mode of operation of said vehicle causing said first switching device to periodically connect and disconnect said motor and said primary source of direct voltage while maintaining said second switching device nonconductive to maintain said motor disconnected from said secondary source of direct voltage to thereby supply said motor solely from said primary source and at a voltage determined by the switching of said first switching device, said control means during a second mode of operation causing alternate and consecutive conduction of said first and second switching devices whereby said motor is alternately and consecutively connected to said primary source of direct voltage and said secondary source of direct voltage, and means responsive to a predetermined electrical loading condition of said primary source of direct voltage when said control means is operating in said first mode of operation for causing said control means to shift from said first mode of operation to said second mode of operation.