Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02J—ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
  • H02J7/00—Circuit arrangements for charging or discharging batteries or for supplying loads from batteries
  • H02J7/90—Regulation of charging or discharging current or voltage
  • H02J7/971—Regulation of charging or discharging current or voltage the charge cycle being controlled or terminated in response to non-electric parameters
  • H02J7/975—Regulation of charging or discharging current or voltage the charge cycle being controlled or terminated in response to non-electric parameters in response to temperature
  • H02J7/977—Regulation of charging or discharging current or voltage the charge cycle being controlled or terminated in response to non-electric parameters in response to temperature of the battery

Definitions

• the present invention relates to a charging device for rapidly charging a capacitor.
• a battery is used as a power source. In such a case, if the power supply is cut off for some reason, the hydraulic control can not be performed, and the vehicle can not be braked.
• Japanese Patent Laid-Open Publication No. 5-116571 is known as a charging device for a battery for a notch assistance at engine start.
• a capacitor having a capacitance of several tens of farads after engine start-up is rapidly charged to a predetermined voltage within a relatively short time of about 100 seconds, for example. It is required to
• FIG. 13 shows an example of a conventional charging device for rapid charging with a constant current.
• the operation of this circuit is as follows. That is, the charging current I is supplied to the capacitor 2 having a capacitance of several tens of farads via the charging element 1 attached to the heat sink (not shown) from the constant voltage source V.
• the charge current I is detected by the current detection unit 3, converted to the voltage V 3, and then the first of the constant current control circuit 4. Input to input terminal 4a.
• a reference voltage 5 is given to the second input terminal 4 b of the constant current control circuit 4.
• a voltage corresponding to the difference between the voltage V 3 detected by the current detection unit 3 and the reference voltage 5 is taken out to the output terminal 4 c of the constant current control circuit 4.
• the constant current control circuit 4 amplifies the voltage of the difference between the two input to the first input terminal 4a and the second input terminal 4b.
• the voltage V 4 extracted from the output terminal 4 c of the constant current control circuit 4 is fed back to the control terminal side of the charging element 1 through the resistor 6.
• the charging current I flowing to the charging element 1 is controlled to be constant, and the capacitor 2 is charged to a voltage substantially equal to the constant voltage source V.
• FIG. 14A, FIG. 14B and FIG. 14C respectively show the change with time of various characteristics of the conventional charging device shown in FIG.
• the horizontal axis of FIG. 14A-FIG. 14C shows charge time t.
• the charge start time is indicated by tO
• the charge completion time is indicated by t2 (100 seconds).
• the vertical axes in FIG. 14A to FIG. 14C show various characteristics.
• the vertical axes in FIG. 14A, FIG. 14B and FIG. 14C respectively represent the charging voltage VC and charging current I of capacitor 2, the power dissipation W consumed by charging element 1, and the surface temperature TH of charging element 1
• the changes over time in the internal temperature Tjc are shown.
• the charging device shown in FIG. 13 is of a type that performs constant current control, so as shown in FIG. Flow to the As a result, the charging voltage VC of the capacitor 2 rises with time, and becomes approximately equal to the voltage of the constant voltage source V at t2 of the charging completion time.
• FIG. 14B shows a time-dependent change of the power loss W consumed by the charging element 1 in the charging process. That is, since the charging voltage VC is not applied to the capacitor 2 at the initial stage of charging, the voltage of the constant voltage source V is applied to the charging element 1. Thereafter, as the charging progresses, the charging voltage VC of the capacitor 2 rises and the voltage applied to the charging element 1 decreases. Therefore, as shown in FIG. 14B, the power loss W shows the maximum value at the charge start time tO, and thereafter decreases with the progress of the charge.
• FIG. 14C shows the temperature change of the charging element 1 during charging. Since the charging element 1 that was initially at room temperature TO generates heat due to the power loss W, the internal temperature Tjc of the charging element 1 rises. Along with that, the surface temperature TH of the charging element 1 also rises.
• the power loss W decreases with the passage of charging time. Go. Therefore, as shown in FIG. 14C, the internal temperature Tjc of the charging element 1 exhibits the maximum value Tjcmax at time tl, and the subsequent internal temperature Tjc decreases with the passage of time t. Along with that, the surface temperature TH of the charging element 1 exhibits a similar temperature change.
• the problem with such temperature change is that the inside of the charging element 1 is kept at a high temperature by the power loss W. That is, there is a problem that the inside of the charging element 1 receives a thermal shock every time the vehicle is started.
• the present invention overcomes the problems of the prior art and provides a highly reliable charging device.
• the charging device of the present invention includes a constant voltage control circuit that controls the charging voltage to the capacitor at a constant level, a current detection unit that detects the charging current in the charging path to the DC power supply capacitor, the voltage of the capacitor, A voltage detection unit that detects a difference between DC power source equivalent voltages, and an integrator that integrates the output signals of the current detection unit and the voltage detection unit.
• the power of the charging element is determined by the output signal output of the integrator.
• the capacitor is controlled to be controlled to the value of, and the charging element is controlled by the constant voltage control circuit to charge the capacitor to a predetermined voltage near the completion of charging.
• Another charging device of the present invention is a charging device having a charging element connected in series between a DC power supply and a capacitor, and charging the capacitor by the DC power supply via the charging element.
• a constant voltage control circuit that controls the charging voltage of the capacitor constant, a current detection unit that detects the charging current in the charging path from the DC power supply to the capacitor, a current limiting unit that controls the charging current to the capacitor, A voltage detection unit that detects a difference between DC power source equivalent voltages and an integrator that integrates the output signals of the current detection unit and the voltage detection unit, and controls the power of the charging element to a predetermined value by the output signal of the integrator. While charging the capacitor to a predetermined voltage by limiting the maximum value of the charging current by the current limiting unit near the end of charging, and then charging the charging element by the constant voltage control circuit. Controlled to a charging device for charging the capacitor to a predetermined voltage.
• Still another charging device of the present invention is a charging device having a charging element connected between a DC power supply and a capacitor, and charging the capacitor by the DC power supply via the charging element.
• a constant current control circuit that controls the charging current to the capacitor at a constant level, a constant voltage control circuit that controls the charging voltage to the capacitor, a capacitor voltage detection unit that detects the voltage of the capacitor, a current at the constant current control circuit Based on the output of the capacitor voltage detector so that the average power of the charging element in the charging process becomes constant when the charging element is controlled by the output signal of the constant current control circuit.
• This is a charging device that switches a plurality of charging currents to charge a capacitor, and when near charging completion, controls a charging element by a constant voltage control circuit to charge the capacitor to a predetermined voltage.
• the charging apparatus of the present invention with such a configuration, constant power is applied to the charging element, and the internal temperature of the charging element mounted on the charging apparatus gradually rises. This can suppress an increase in the internal temperature of the charging element.
• the internal temperature of the charging element can be kept low, the thermal shock that occurs each time the vehicle is started can be mitigated, and the reliability of the charging element can be improved.
• FIG. 1 is a block circuit diagram of a charging apparatus according to a first embodiment of the present invention.
• FIG. 2 is a circuit diagram of a voltage detection unit and an integrator of the charging apparatus according to the first embodiment of the present invention.
• FIG. 3A shows a time-dependent change of capacitor charging current and voltage during charging operation of the charging apparatus according to the first embodiment of the present invention.
• FIG. 3B shows a time-dependent change of the power loss of the charging element according to Embodiment 1 of the present invention.
• FIG. 3C shows a time-dependent change of the internal temperature of the charging element according to Embodiment 1 of the present invention and the surface temperature thereof.
• FIG. 4 is a block circuit diagram of a charging device according to a second embodiment of the present invention.
• FIG. 5 is a circuit diagram of a voltage detection unit, a power switching unit, and an integrator of the charging apparatus according to Embodiment 2 of the present invention.
• FIG. 6A shows a time-dependent change of capacitor charging current and voltage during charging operation of the charging apparatus according to Embodiment 2 of the present invention.
• FIG. 6B shows a time-dependent change in power loss of the charging element according to Embodiment 2 of the present invention.
• FIG. 6C shows a change with time of the internal temperature of the charging element according to Embodiment 2 of the present invention and the surface temperature thereof.
• FIG. 7 is a block circuit diagram of a charging device according to a third embodiment of the present invention.
• FIG. 8A shows a time-dependent change of capacitor charging current and voltage during charging operation of the charging device according to the third embodiment of the present invention.
• FIG. 8B shows a time-dependent change in power loss of the charging element according to Embodiment 3 of the present invention.
• FIG. 8C shows a time-dependent change of the internal temperature of the charging element according to Embodiment 3 of the present invention and the surface temperature thereof.
• FIG. 9 is a block circuit diagram of a charging device according to Embodiment 4 of the present invention.
• FIG. 10A shows a time-dependent change of capacitor charging current and capacitor voltage at the time of charging operation of the charging device according to the fourth embodiment of the present invention.
• FIG. 10B shows a time-dependent change of power loss of the charging element according to the fourth embodiment of the present invention.
• FIG. 10C shows a change with time of the internal chip temperature of the element and the element surface temperature according to the fourth embodiment of the present invention.
• FIG. 11 is a block circuit diagram of the periphery of the charging element of the charging apparatus according to the fifth embodiment of the present invention.
• FIG. 12 shows a time-dependent change of capacitor charging current of the charging device according to the fifth embodiment of the present invention.
• FIG. 13 is a block circuit diagram of a conventional charging device.
• FIG. 14A shows time-dependent changes of capacitor charging current and voltage during charging operation of the conventional charging device.
• FIG. 14B shows a time-dependent change of power loss of the conventional charging element.
• FIG. 14C shows the change over time of the internal temperature of the conventional charging element and its surface temperature. Explanation of sign
• FIG. 1 is a block circuit diagram of the charging device.
• FIG. 2 is a circuit diagram of a voltage detection unit and an integrator of the charging device.
• Fig. 3A shows the charging current of the capacitor and the time-dependent change of the voltage generated in the capacitor
• Fig. 3B shows the aging of the power loss of the charging element
• Fig. 3C shows the aging of the internal temperature and the surface temperature of the charging element.
• DC power supply 10 and capacitor 11 are connected to charging device 100.
• the DC power supply 10 supplies power to the charging device 100, and the capacitor 11 supplies power to the DC power supply 10. The force causes the charge to accumulate through the charging device 100.
• Capacitor 11 is formed of, for example, an electric double layer capacitor. As a result, it becomes possible to discharge a large amount of power in an emergency when braking the vehicle, which can not only charge the battery rapidly.
• the charging device in the first embodiment is, for example, an electric double layer capacitor because it is exemplified as being used for vehicle braking.
• the capacitor may be a commonly used capacitor in general charging applications.
• a charging circuit 100 is connected with a backup circuit 200 which is an electronic device 14 such as a switch 12, a diode 13 and a braking device of a vehicle.
• a backup circuit 200 which is an electronic device 14 such as a switch 12, a diode 13 and a braking device of a vehicle.
• the switch 12 is closed by the signal of a sensor circuit (not shown) that detects a drop in the voltage of the DC power supply 10, and the electronic device 14 via the diode 13.
• the capacitor 11 is configured to be supplied with a charge.
• the charging element 15 controls the current for accumulating charge in the capacitor 11.
• charging element 15 is attached to a heat sink (not shown), and provided in a connection path between DC power supply 10 and capacitor 11. Connect the anode of diode 16 to DC power supply 10 side and the power sword to charging element 15 to prevent reverse current from flowing to DC power supply 10! /.
• the voltage appearing at the terminal 18, that is, the voltage VC generated at both terminals of the capacitor 11 and the reference voltage 19 are separately input to two input terminals of the constant voltage control circuit 17.
• the voltage differentially amplified by the constant voltage control circuit 17 is input to the control synthesis circuit 20.
• the output terminal of the control synthesis circuit 20 is connected to the charging element 15 connected to the capacitor 11. Thereby, the charging voltage to the capacitor 11 can be kept constant.
• the circuit operation of the constant voltage control circuit 17 will be described later.
• the voltage detection unit 21 includes a first input terminal 21a and a second input terminal 21b.
• a voltage input to the charging element 15, that is, an input voltage V15a corresponding to the DC power supply 10 is input to the first input terminal 21a.
• the voltage of the terminal 18, that is, the voltage VC of the capacitor 11 is input to the second input terminal 21b.
• the voltage detection unit 21 detects the voltage of the difference between the two, further amplifies the magnitude thereof, and outputs the amplified voltage to the output terminal 21c.
• Output of voltage detection unit 21 The output voltage extracted from the terminal 21 c is input to the integrator 22.
• Current detection unit 23 is generally constituted by a resistor but other elements, for example, a current sensor that outputs a voltage proportional to the current. Convert current to voltage. The voltage extracted from the current detection unit 23 is input to the integrator 22 via the terminal 22a.
• the integrator 22 integrates the voltages of the voltage detection unit 21 and the current detection unit 23 to calculate electric power.
• the output voltage of the integrator 22 is input to the control synthesis circuit 20 via the terminal 22b. The detailed operation of the integrator 22 will be described later.
• the control synthesis circuit 20 is composed of resistors 24a to 24d, a transistor 25, and diodes 26a and 26b.
• One terminal of each of the resistors 24a and 24b is connected to the collector and emitter of the transistor 25 respectively.
• the other terminals of the resistors 24a and 24b are connected to the resistor 28 and the ground terminal (GND), respectively.
• the base of transistor 25 is provided with a base voltage determined by the division of resistors 24c and 24d.
• diodes 26a and 26b are connected to the base of the transistor 25.
• the diodes 26a, 26b constitute a so-called OR circuit.
• diodes 26 a and 26 b are separately connected to the multiplier 22 and the constant voltage control circuit 17 to constitute an OR circuit on the input side of the control synthesis circuit 20.
• the control synthesis circuit 20 is configured to be controlled by the operation of either the integrator 22 or the constant voltage control circuit 17.
• the control synthesis circuit 20 drives the transistor 25 by a current supplied via the resistor 24 c connected to the internal power supply 27, and is connected between the other terminal of the resistor 24 a and the charging element 15.
• the charging element 15 is controlled via the resistor 28.
• the control of the base voltage of the transistor 25 is determined by the force-sword voltage of the diodes 26a and 26b configured in an OR circuit.
• FIG. 2 shows a specific circuit configuration of voltage detection unit 21 and integrator 22 shown in FIG.
• the integrator 22 is composed of a comparator 29, a sawtooth oscillator 30 for generating stable frequency and voltage, a smoother 34 comprising an amplifier 31 and resistors 32a and 32b and a capacitor 33, and a reference voltage 35.
• a voltage detection unit 21 is connected to the integrator 22 via a terminal 21 c.
• the voltage detection unit 21 comprises a differential amplifier 36, resistors 38a, 38b, 38c, 38d and terminals 21a, 21b, 21c.
• the voltage on the input side of the charging element 15 is applied via the terminal 21a to the non-inverting input terminal (+) of the differential amplifier 36 through the voltage divided by the resistors 38a and 38b.
• the voltage VC of the capacitor 11, ie, the voltage of the terminal 18, is input to the inverting input terminal (one) of the differential amplifier 36 via the terminal 21b and the resistor 38d.
• a negative feedback resistor 38c is connected between the output terminal 21c of the differential amplifier 36 and the inverting input terminal (one).
• the differential amplifier 36 amplifies the differential voltage between the inverting input terminal (one) and the noninverting input terminal (+). That is, the voltage proportional to the input voltage input to the charging element 15 is compared with the voltage VC appearing on the capacitor 11, and the difference voltage between them is amplified and output to the output terminal 21c.
• the output voltage output to the output terminal 21 c is input to the non-inverted input terminal (+) of the comparator 29.
• a sawtooth voltage is input from the sawtooth oscillator 30 to the inverting input terminal (one) of the comparator 29.
• the comparator 29 is configured to determine the difference between the two voltages. That is, while the output voltage of the voltage detection unit 21 is higher than the voltage of the sawtooth oscillator 30, the output of the current detection unit 23 is input to the smoothing unit 34 from the terminal 22a.
• the difference voltage between the charging current I and the input voltage VI 5a of the charging element 15 and the voltage VC of the capacitor 11 is integrated from the output terminal 22b of the smoothing unit 34, which corresponds to a universal power.
• a signal is output.
• the output voltage output from the output terminal 22 b is controlled to be equal to the reference voltage 35 and input to the control synthesis circuit 20.
• the power of the charging element 15 is controlled to be constant during the charging process.
• FIG. 3A, FIG. 3B and FIG. 3C show the change with time of the charging device configured as described above.
• the operating conditions of the present invention were set so as to use the same heat sink and charging element as in the prior art, and to have the same charging completion time t2.
• the horizontal and vertical axes in FIGS. 3A to 3C are the same as in FIG. 14 showing the conventional example. That is, the horizontal axis indicates time t. The charge start time is indicated by tO, and the charge completion time is indicated by t2 (100 seconds).
• the vertical axis shows various electrical characteristics.
• the vertical axes in FIGS. 3A, 3B and 3C respectively represent the charging voltage VC and charging current I of the capacitor 11, the power dissipation W consumed by the charging element 15, and the surface temperature of the charging element 15 as TH.
• the internal temperature of each is denoted as Tj.
• FIG. 3C also shows temporal changes in internal temperature Tjc of the conventional charging element 1 for comparison.
• the first embodiment is different from the conventional example 14 in that the surface temperature TH of the charging element 15 and its surface temperature are controlled by controlling the power loss W (see FIG. 3B) in the charging process constant.
• the internal temperature Tj is a substantially straight line and a gradual rise.
• maximum value Tjmax of internal temperature Tj of charging element 15 is about 80% of conventional maximum value Tjcmax, and the problem that charging element 15 is exposed to high temperatures is eliminated. be able to.
• the base voltage of the transistor 25 also gradually decreases.
• the forward bias voltage of the charging element 15 is also reduced, and eventually the voltage at the terminal 18 is continuously constant voltage controlled at the constant voltage control voltage Vcs.
• time t2f to time t2 from the above operation can not be defined uniformly, and the apparent voltage generated at terminal 18 depending on the magnitude of the charging current is higher as the internal resistance of capacitor 11 is larger. Become. For this reason, the time to reach the constant voltage control voltage Vcs becomes faster. On the contrary, the time from time t2f to time t2 becomes longer, and depends on the internal resistance of the capacitor. It will be the charging time.
• FIG. 4 to 6C show a charging device according to Embodiment 2 of the present invention.
• FIG. 5 is a circuit diagram of a voltage detection unit, a power switching unit, and an integrator of the charging device.
• Figures 6A, 6B and 6C show the time course of the charging operation of the charging device.
• Fig. 6A shows the charging current and capacitor voltage of the capacitor
• Fig. 6B shows the power loss of the charging element
• Fig. 6C shows the change in internal temperature of the charging element and its surface temperature with time.
• FIGS. 4 and 5 the same components as in FIGS. 1 and 2 are respectively assigned the same reference numerals.
• the second embodiment differs from the first embodiment in that the power switching unit 37 is connected between the terminal 21 c of the voltage detection unit 21 and the integrator 22.
• a power switching unit 37 including a hysteresis comparator 38 which compares the reference voltage 35 with the voltage of the terminal 21 c of the voltage detection unit 21 is provided. Furthermore, in the second embodiment, the integrator 22 is provided with resistors 39a, 39b and 39c for switching the reference voltage of the smoothing device 34 by the operation of the hysteresis comparator 38. It is different.
• the charging completion time is t2 100 seconds).
• the hysteresis comparator 38 compares the terminal 21c of the voltage detection unit 21 with the reference voltage 35, and when the output of the terminal 21c becomes larger than a predetermined value determined by the reference voltage 35. , Hysteresis comparator 38 is turned off.
• the output of the smoothing unit 34 is a power signal based on a voltage obtained by resistance-dividing the reference voltage 35 with the resistors 39 b and 39 c.
• the output voltage of the smoothing unit 34 is input to the control and synthesis circuit 20 through the terminal 22 b.
• the power loss W of the charging element 15 is controlled to be constant. Charging will proceed.
• 6A, 6B and 6C show the capacitor charging current and voltage during charging operation of the charging device according to Embodiment 2 of the present invention, the power loss of the charging element, and the internal temperature of the charging element, respectively. And the time-dependent change of the surface temperature is shown, respectively.
• FIG. 5 In FIG. 5, FIG. 6A, FIG. 6B and FIG. 6C, when time t3 is reached, the output voltage of output terminal 21c of voltage detection unit 21 becomes lower than a predetermined value determined by reference voltage 35, and hysteresis comparator 38 It turns on.
• the resistors 39a and 39b are connected in parallel, and the output of the smoother 34 is a power determined by a voltage smaller than a voltage obtained by resistively dividing the reference voltage 35 by the resistors 39b and 39c. Since it becomes a signal, the power loss W of the charging element 15 is controlled to be small.
• charging current I increases as the difference between input voltage V15 of charging element 15 and voltage VC of capacitor 11 decreases in the charging process. , And can be suppressed smaller than the charging current I in FIG. 3A.
• the voltage from the constant voltage control circuit 17 is preferentially output to the control synthesis circuit 20. Ru.
• the charging of the capacitor 11 proceeds and the charging element 15 is controlled with a constant voltage gradually, so the charging current I takes about several seconds and decreases.
• the first terminal 21a of the voltage detection unit 21 is electrically connected to the common connection point of the charging element 15 and the diode 16 through the connection line 21ab.
• the terminal 21a is connected to the common connection point between the DC power supply 10 and the diode 16 via the connection line 21ac. Just connect.
• the voltage detection unit 21 measures the voltage of the circuit portion including all the circuit components constituting the circuit in which the charging current flows between the DC power supply 10 and the capacitor 11. As a result, since the voltage detection unit 21 always measures in a state including the voltage of the diode 16, it is possible to control so that the total power of the circuit components including the diode 16 becomes constant. As a result, the heat generation of the circuit element including the diode 16 interposed in the charging path can be suppressed, and a highly reliable charging device can be provided.
• current detection unit 23 is connected between DC power supply 10 and terminal 18 of capacitor 11, and a voltage difference including the voltage of current detection unit 23 is detected by voltage detection unit 21. It may be configured to measure by
• FIG. 7 is a block circuit diagram of the charging device.
• Fig. 8A shows the capacitor charging current and the capacitor voltage
• Fig. 8B shows the power loss of the charging element
• Fig. 8C shows the change over time of the internal temperature of the charging element and its surface temperature.
• the third embodiment shown in FIG. 7 includes a current limiter 40 and a diode 41 in addition to the configuration of the first embodiment.
• the current limiting unit 40 is, for example, a differential amplifier, and the voltage of the current detecting unit 23 and the reference voltage 19 are separately provided to the two inputs of the current limiting unit 40. Further, the output terminal of the current limiting unit 40 is connected to the control synthesis circuit 20 via the diode 41.
• the diode 41 constitutes a so-called OR circuit together with the diodes 26a and 26b. That is, in the third embodiment, in addition to the integrator 22 and the constant voltage control circuit 17, a current limiting unit 40 is newly connected to the input side of the control combining circuit 20, and a new OR circuit is provided by these circuits. It is composed.
• the charge loss from the DC power supply 10 to the capacitor 11 proceeds by controlling the loss power W of the charging element 15 constant as in the first embodiment until the charge start time tO power and the charge completion time t2. As a result, the charging current I increases as shown in FIG. 8A.
• the output voltage of the current detection unit 23 also increases.
• the current limiting unit 40 outputs a signal to the control / combination circuit 20 via the diode 41 so that the voltage generated in the current detection unit 23 becomes equal to the reference voltage 19, so the charging current has a maximum value Im at time t5. Charging proceeds in a restricted state.
• charging element 15 is controlled by constant voltage control circuit 17 as in the first embodiment so that overcurrent does not flow. While charging the capacitor 11 to a predetermined voltage and completing the charging operation at the charging completion time t2.
• the surface temperature TH of the charging element 15 and the internal temperature thereof over time when charged in this way are shown in FIG. 8C. It has been found that the surface temperature TH of the charging element 15 and the maximum temperature Tjmax of its internal temperature Tj are even lower than those in the case of the first embodiment.
• the circuit components constituting the charging path can flow the charging current to the charging device within the range of the rated current, so that the maximum temperature Tjmax in the charging element 15 is further lowered. Can provide a reliable charging device.
• connection line 21 a b connected to the terminal 21 a of the voltage detection unit 21 is not connected to the common connection point of the diode 16, the charging element 15 and the resistor 28. It may be connected to the common connection point between the DC power supply 10 and the diode 16 as shown in 21ac (see FIG. 7).
• the output voltage measured by the voltage detection unit 21 includes all the circuit components that constitute the circuit in which the charging current flows between the DC power supply 10 and the capacitor 11 including the diode 16. Since it becomes a voltage, it is possible to suppress heat generation of circuit parts such as a transistor, a diode, a resistor, and a capacitor, which are present in the charging path, and it is possible to provide a charging apparatus having high V and reliability.
• the diode 16 may be attached to a heat sink (not shown) to which the charging element 15 is attached. Thereby, the heat generated from charging element 15 and diode 16 can be efficiently conducted to the heat sink, and the maximum temperature Tjmax inside charging element 15 can be further reduced. Can.
• FIG. 9 to 10C show a charging device according to a fourth embodiment of the present invention.
• FIG. 9 is a block circuit diagram of the charging device.
• Fig. 10A shows the capacitor charging current and the capacitor voltage
• Fig. 10B shows the power loss of the charging element
• Fig. 10C shows the internal temperature of the charging element and its surface temperature with time.
• the capacitor voltage detection unit 42 detects the voltage of the capacitor 11, and outputs an on / off signal according to the voltage.
• the current switching unit 43 receives the output signal of the capacitor voltage detection unit 42 and turns on and off the switch 45 connected to the resistor 44 to change the charging current.
• capacitor voltage detection unit 42 and current switching unit 43 are configured by a microcomputer. That is, the voltage VC of the capacitor 11 is detected as a digital signal by an AZD converter (not shown) built in the microcomputer. Based on this digital signal, it is determined by the microcomputer whether or not a predetermined voltage Va described later is generated or not, and the switch 45 of the current switching unit 43 is switched according to the result of the determination. With such a configuration, the capacitor voltage detection unit 42 and the current switching unit 43 can be simplified and downsized.
• the current / voltage conversion voltage and the reference voltage 19 are supplied from the current detection unit 23 to the constant current control circuit 46, and the output voltage is input to the control synthesis circuit 20.
• a signal for turning on the switch 45 of the current switching unit 43 is output from the capacitor voltage detection unit 42.
• the voltage on the reference side of the constant current control circuit 46 is set to a voltage obtained by dividing the reference voltage 19 by a parallel resistor consisting of a resistor 44 and a resistor 47 and a resistor 48, whereby the charging current is constant current II 1 Works to be
• voltage VC of capacitor 11 is higher than predetermined voltage Va at time t7.
• a signal to turn off the switch 45 is output from the capacitor voltage detection unit 42 and switched to the constant current 112.
• FIG. 10B and FIG. 10C use the same heat sink and charging element as in the prior art to cut off the charging current so that charging is completed from DC power supply 10 to capacitor 11 in the same charging time t2
• the power loss and heat generation of the charging element 15 when charging instead are shown.
• the power loss of the charging element 15 is denoted by Wl l and W12, respectively.
• FIG. 10B shows the average power Wa (shown by the lower right diagonal line in the figure) obtained by averaging the loss power W11 of time t7 from the charge start time tO of the charge process from the charge start time tO
• Charge flows 111 and 112 and predetermined voltage Va are set so that average power Wb (shown by lower left diagonal lines in the figure) obtained by averaging power loss W12 from time t7 to time t8 at times t7 to t8 is substantially constant.
• average power Wb shown by lower left diagonal lines in the figure
• the heat generation of the charging element 15 generated from the charging start time t0 to the charging completion time t2 is a two-stage force as shown in FIG. 10C. Also, if the internal temperature Tjc of the conventional charging element 1 exceeds the maximum temperature Tjcmax V, the failure can be eliminated.
• the maximum internal temperature Tjmax (maximum value of the internal temperature Tj) of the charging element 15 can be reduced under the same charging time, charging element and heat sink conditions as before.
• a highly reliable charging device can be realized.
• switching of the current has been described as two stages. However, the current may be switched in two or more stages depending on factors such as the difference in heat transfer characteristics depending on the shape of the heat sink.
• FIG. 11 to 12 show a charging device according to a fifth embodiment of the present invention.
• the fifth embodiment will be described in connection with the fourth embodiment.
• FIG. 11 is a block circuit diagram around the charging element of the charging device according to the fifth embodiment.
• FIG. 12 shows the time course of the capacitor charging current of the charging device.
• the same reference numerals as in FIG. 9 denote the same parts in FIG.
• FIG. 11 is an excerpt of the charging element 15 and the control synthesis circuit 20 in the charging device 100 shown in the fourth embodiment.
• another charging element 49 is connected to the charging element 15 in parallel thereto.
• the control terminals of the charging elements 15, 49 are separately connected to one terminal of switches 50a and 50b for transmitting the charge control signal output from the control combining circuit 20.
• the other terminals of the switches 50 a and 50 b are connected in common to the control combining circuit 20.
• the switches 50 a and 50 b are each driven on and off by a switch drive unit 51.
• the circuit units such as the control synthesis circuit 20, the switch drive unit 51, and the switches 50a and 50b are constituted by microcomputers, so the circuit is simplified and the cost and size of the charging apparatus 100 can be reduced.
• the switch driver 51 outputs signals 51a and 51b alternately turned on and off in the same cycle.
• the charging control signal output from the control combining circuit 20 is alternately transmitted to the charging elements 15 and 49 via the switches 50a and 50b to perform charging.
• FIG. 12 shows the change with time of the charge current.
• the currents flowing through the charging element 15 and the charging element 49 are denoted by If 1 and If 2 respectively.
• the power loss of the charging element from the charging start time tO to the charging completion time t2 can be equally distributed to the two charging elements 15, 49.
• the heat generated by this power loss is transferred to the heat radiation fins (not shown) of the charging elements 15 and 49 to the heat radiation plate, and the thermal resistance between the radiation fins and the heat radiation plate is equivalent to 1/2.
• the temperature rise of the charging elements 15, 49 can be reduced.
• the duty of currents If1 and H2 is set to 50%, that is, the on period is set to 1Z2 of the whole. Therefore, as a result of conducting various studies under this condition, it was found that it is desirable to set the on / off cycle of the charging elements 15, 49 to 20 milliseconds or less where the thermal resistance reduction characteristics can be applied. As a result, the thermal resistances of charging elements 15, 49 can be reduced to drive them, thereby reducing their maximum internal temperature Tjmax. be able to.
• three or more forces using two charging elements 15 and 49 may be used.
• all charging elements are connected in parallel as in the fifth embodiment, and the same number of switches are prepared.
• the charging elements are driven in order by sequentially switching the switches. As a result, it is possible to further suppress the heat generation of the charging elements 15, 49.
• the maximum temperature Tjmax of the charging elements 15, 49 can be reduced, and a highly reliable charging device can be provided.
• the charging apparatus to which the present invention can be applied can keep the temperature inside the charging element low.
• the reliability of the charging element can be improved. For this reason, since it is useful as a charging device etc. which charge especially a capacitor rapidly, its industrial applicability is high.

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• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Charge And Discharge Circuits For Batteries Or The Like (AREA)

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• 2005
  • 2005-06-02 JP JP2005162252A patent/JP2006340505A/ja active Pending
• 2006
  • 2006-06-02 WO PCT/JP2006/311064 patent/WO2006129782A1/ja not_active Ceased
  • 2006-06-02 US US11/909,751 patent/US7855533B2/en active Active
  • 2006-06-02 EP EP06747108A patent/EP1860752A1/en not_active Withdrawn

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