KR101983253B1 - Precharge system operating according to overheat preventing algorithm and battery pack including the same - Google Patents

Abstract

The present invention discloses a precharge system that performs a precharge cycle in accordance with an overheat prevention algorithm.
A precharge system according to an embodiment of the present invention includes: a precharge relay connected in parallel with a main relay; A precharge resistor connected in series with the precharge relay; And a precharge cycle in which a precharge cycle period that is periodically repeated, a precharge cycle period that is a idle period between the precharge cycles, and a precharge cycle that is a period after the precharge cycle and the precharge cycle period form one cycle The precharge period and the precharge period are repeated until the temperature of the precharge resistor, which has changed as the crossing between the precharge period and the precharge period is repeated, reaches a threshold temperature, Is repeated.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a precharge system that operates in accordance with an overheat prevention algorithm, and a battery pack including the precharge system.

FIELD OF THE INVENTION The present invention relates to precharge techniques and, more particularly, to precharge systems that operate in accordance with an algorithm that prevents overheating of precharge resistors.

2. Description of the Related Art In recent years, demand for portable electronic products such as notebook computers, video cameras, and portable telephones has been rapidly increased, and electric vehicles, storage batteries for energy storage, robots, and satellites have been developed in earnest. Are being studied actively.

The secondary rechargeable batteries are nickel-cadmium batteries, nickel-hydrogen batteries, nickel-zinc batteries, and lithium secondary batteries. Among them, lithium secondary batteries have almost no memory effect compared to nickel- It is very popular because of its low self-discharge rate and high energy density.

On the other hand, the secondary battery transmits and receives electric power to and from a charge / discharge system such as a load or a charger. In order to prevent an overcurrent or an inrush current from flowing during the charging / discharging process, The charging system according to the related art has a main relay, a ground relay and a precharge relay, and by performing precharging by turning on the ground relay and the precharge relay, an overcurrent or an inrush current is generated when the main relay is turned on To prevent flow.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic view showing a configuration of a charging system having a precharge system according to the prior art; FIG. Referring to FIG. 1, the charging system 30 includes a main relay 110, a ground relay 120, a precharge relay 130, and a precharge resistor 140. The charging system (30) is provided between the battery (10) and the load (20).

The operation of the charging system 30 according to the prior art will be briefly described as follows.

First, the ground relay 120 is turned on. Then, the precharge relay 130 is turned on. As the ground relay 120 and the precharge relay 130 are turned on, a current path is formed between the battery 10 and the load 20 to precharge the load 20. At this time, the precharge resistor 140 prevents the overcurrent or the inrush current from flowing in the current path.

Next, when the charging of the load 20 is sufficiently performed, the main relay 110 is turned on. When the main relay 110 is turned on, most of the current flows through the main relay 110. The precharge relay 130 may then be selectively turned off.

The precharge resistor 140 connected in series to the precharge relay 130 and the precharge relay 130 prevents the overcurrent or the inrush current in the initial process of connecting the battery 10 and the load 20 . However, when performing the above process, the precharge resistor 140 may inevitably generate heat, and the precharge resistor 140 may deteriorate. Therefore, in order to reduce the deterioration of the precharge resistor 140, a sufficient cooling process must be performed, and in particular, a cooling process optimized for the precharging operation needs to be performed.

It is an object of the present invention to provide an overheat prevention algorithm which is developed to solve the problems of the precharge system according to the prior art and can reduce deterioration of precharge resistance.

Other objects and advantages of the present invention will become apparent from the following description, and it will be understood by those skilled in the art that the present invention is not limited thereto. It is also to be understood that the objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations thereof.

Various embodiments of the present invention for achieving the above object are as follows.

(1) A precharge system comprising: a precharge relay connected in parallel with a main relay; A precharge resistor connected in series with the precharge relay; And a precharge cycle in which a precharge cycle period that is periodically repeated, a precharge cycle period that is a idle period between the precharge cycles, and a precharge cycle that is a period after the precharge cycle and the precharge cycle period form one cycle The precharge period and the precharge period are repeated until the temperature of the precharge resistor, which has changed as the crossing between the precharge period and the precharge period is repeated, reaches a threshold temperature, And repeats the cycle of the precharge operation.

(2) In (1), the controller may control the precharge period and the precharge period so that the precharge period and the precharge period are alternately repeated until the temperature of the precharge resistance reaches the threshold temperature, And determines the size of the precharge cycle period and the precharge cycle period according to the determined number of times of the precharge cycle, the number of times of the precharge cycle period, and the size of the precharge cycle period The precharge system comprising:

(3) In (2), the control unit may be configured such that the amount of change in the temperature of the pre-charge resistance that changes as one pre-charge period and the pre-charge idle period are cross- And determines the size of the precharge hibernation period and the number of repetitions of the precharge period and the precharge hibernation period so as to be k times the variation amount of the temperature of the charge resistance.

(4) In (3), the controller may determine the size of the pre-charge idle period and the number of repetitions of the pre-charge period and the pre-charge idle period using the following equation: .

Here, n is the number of iterations, T _threshold is the critical temperature of the pre-charging period and the precharge idle period, T _normal is the operating temperature, a temperature rising coefficient of the pre-charging resistor, b is the cooling coefficient of the pre-charging resistor, t _precharge is Size of pre-charge interval

(5) The pre-charge system according to any one of (1) to (4), wherein the size of the pre-charge interval is a preset value or a value input from the outside by the control unit.

(6) The pre-charging system according to any one of (3) to (5), wherein the control unit receives the value of k from the outside.

(7) In any one of (2) to (6), the controller may determine the size of the pre-charge cooling interval so that the pre-charge resistance is cooled during the pre-charge cooling interval to reach an operating temperature, And the controller performs the precharge cycle according to the determined size of the precharge cooling section.

(8) The pre-charge system according to (7), wherein the controller determines the size of the pre-charge cooling section using the following equation.

Where T _threshold is the critical temperature, T _normal is the operating temperature, b is the cooling coefficient of the pre-charge resistance, t _cooldown is the size of the pre-

(9) In any one of (1) to (8), the pre-charge interval is a period in which the pre-charge relay is turned on, and the pre-charge idle period and the pre- Lt; RTI ID = 0.0 > 1, < / RTI >

(10) A charging system comprising a precharge system according to any one of (1) to (9).

(11) A battery pack comprising a precharge system according to any one of (1) to (9).

(12) A vehicle comprising a pre-charging system according to any one of (1) to (9).

(13) A method of precharging by using a precharge system including a precharge relay connected in parallel with a main relay, and a precharge resistor serially connected to the precharge relay, A precharge step of alternately repeating the turn-on and turn-off of the precharge relay so that the precharge break period is repeated; And a cooling step of turning off the pre-charge relay so that the pre-charge resistance is cooled after the pre-charging step, wherein the pre-charging step is performed by repeating the pre-charging period and the pre- Wherein the precharge period and the precharge period are alternately repeated until the temperature of the changed precharge resistance reaches the threshold temperature.

(14) The method as described in (13), wherein the pre-charge step is preceded by the pre-charge period so that the pre-charge period and the pre-charge idle period are alternately repeated until the temperature of the pre- And determining a size of the precharge period and the number of repetitions of the precharge period, the precharge period, the precharge period, the charge period, the number of repetitions of the precharge period and the precharge period, And repeating the turn-on and turn-off of the precharge relay according to the number of repetitions of the interval and the size of the precharge period.

(15) The method as set forth in (14), wherein the determining step comprises a step of determining whether a change in the temperature of the pre-charge resistor, which varies as a single pre-charge interval and a pre- And determining the number of times the precharge hibernation interval is repeated and the number of times the precharge hibernation interval is repeated so that the precharge hibernation duration is k times the variation amount of the temperature of the precharge hysteresis.

(16) In the step (15), the determining step may determine the size of the pre-charge idle period and the number of repetitions of the pre-charge period and the pre-charge idle period using the following equation: Charge method.

Here, n is the number of iterations, T _threshold is the critical temperature of the pre-charging period and the precharge idle period, T _normal is the operating temperature, a temperature rising coefficient of the pre-charging resistor, b is the cooling coefficient of the pre-charging resistor, t _precharge is Size of pre-charge interval

(17) The pre-charge method according to any one of (13) to (16), wherein the size of the pre-charge interval is a preset value or an input value before the determining step.

(18) The method of any one of (15) to (17), wherein the method further comprises the step of inputting the value of k before the determining step.

(19) The method as described in any one of (14) to (18) above, wherein after the determining, determining the size of the pre-charge cooling section such that the pre-charge resistance is cooled to reach an operating temperature And the cooling step is a step of turning off the pre-charge relay according to a size of the pre-charge cooling section determined in the step of determining the size of the pre-charge cooling section.

(20) The pre-charge cooling method according to (19), wherein the size of the pre-charge cooling interval is determined by using the following equation.

Where T _threshold is the critical temperature, T _normal is the operating temperature, b is the cooling coefficient of the pre-charge resistance, t _cooldown is the size of the pre-

According to an aspect of the present invention, precharging is performed as the precharging interval and the precharging rest interval are alternately repeated until the critical temperature is reached, and after reaching the critical temperature, the precharging cooling period is performed, It is possible to prevent the resistance from being damaged.

According to another aspect of the present invention, it is possible to determine the remaining parameters required to perform the precharge cycle based on the size of the required precharge section, thereby operating the precharge system.

In addition, the present invention can have various other effects, and other effects of the present invention can be understood by the following description, and can be more clearly understood by the embodiments of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate preferred embodiments of the invention and, together with the description of the invention given below, serve to further the understanding of the technical idea of the invention. And should not be construed as limiting.
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic view showing a configuration of a charging system having a precharge system according to the prior art; FIG.
2 is a diagram illustrating a configuration of a precharge system according to an embodiment of the present invention.
3 is a diagram illustrating a precharge cycle according to an embodiment of the present invention.
4 is a flowchart illustrating a precharge method according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It should be construed as meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined.

Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.

In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

Throughout the specification, when an element is referred to as including an element, it does not exclude other elements unless specifically stated otherwise, but may also include other elements. Furthermore, the term " control unit " as described in the specification means a unit for processing at least one function or operation, and may be implemented by hardware, software, or a combination of hardware and software.

In addition, in the entire specification, when a part is connected to another part, it is not only a case where it is directly connected, but also a case where it is indirectly connected with another element in between .

2 is a diagram illustrating a configuration of a precharge system according to an embodiment of the present invention.

Referring to FIG. 2, a precharge system 100 according to an embodiment of the present invention constitutes a part of a charging system 30 provided between a battery 10 and a load 20. In the embodiment of Figure 2, the load 20 is a motor 22 connected to an inverter 21 and an inverter 21. The charging system 30 includes a main relay 110, a ground relay 120, and a precharge system 100.

The main relay 110 and the ground relay 120 are provided on a line connecting the battery 10 and the inverter 21, respectively. The main relay 110 and the ground relay 120 are configured to be selectively turned on or off. The main relay 110 and the ground relay 120 may receive a control signal and turn on or off. At this time, the control signal may be a signal output from the control unit 150, which will be described later.

The precharge system 100 includes a precharge relay 130, a precharge resistor 140, and a controller 150.

The precharge relay 130 is configured to be connected in parallel with the main relay 110. The precharge relay 130 is configured to be selectively turned on or off. The precharge relay 130 may be turned on or off by receiving a control signal of the controller 150, which will be described later.

The precharge resistor 140 is a resistance element connected in series with the precharge relay 130. The precharge resistor 140 prevents a current from flowing to the precharge resistor 140 when precharging is performed, thereby preventing an overcurrent or an inrush current from being generated. The precharge resistor 140 has a predetermined temperature rise coefficient and a predetermined cooling coefficient. Here, the temperature rise coefficient is a measure indicating a temperature amount that rises for a unit time when a voltage is applied to the precharge resistor 140, and the cooling coefficient is a unit time at an operating temperature of the precharge resistor 140 Lt; RTI ID = 0.0 > naturally < / RTI > Generally, the temperature rise coefficient has a value larger than the cooling coefficient.

The controller 150 may output a control signal to the precharge relay 130 to turn on or off the precharge relay 130. [ The controller 150 may be configured to control not only the precharge relay 130 but also the main relay 110 and the ground relay 120 as described above. The controller 150 controls the turn-on / turn-off of the precharge relay 130 in a state in which the ground relay 120 is turned on to perform precharging. That is, when the ground relay 120 is turned on, the controller 150 turns on the pre-charge relay 130 to perform pre-charge, turns off the pre-charge relay 130, 140) is naturally cooled.

Also, the controller 150 may be configured to calculate an equation to perform an algorithm related to pre-charge and cooling, and to receive or store information required for calculation of the equation. According to one embodiment, the controller 150 may be a microprocessor having an arithmetic unit, a storage unit, and an input / output port.

The controller 150 may determine an algorithm for precharging and cooling, and may perform precharging and cooling according to a determined algorithm.

More specifically, the control unit 150 may perform the following precharge cycle. The control unit 150 is configured to perform a precharge interval and a precharge idle interval in an alternating manner, and to perform a precharge interval after the precharge interval and the precharge idle interval are completed. Here, the controller 150 repeatedly repeats the pre-charge interval and the pre-charge idle interval until the temperature of the changed (increased) pre-charge resistance reaches the critical temperature as the pre-charge interval and the pre- .

3 is a diagram illustrating a precharge cycle according to an embodiment of the present invention.

Referring to FIG. 3, the pre-charge cycle according to an embodiment of the present invention includes a pre-charge period, a pre-charge idle period, and a pre-charge cooling period. As shown in FIG. 3, the pre-charge interval and the pre-charge idle interval are performed in an alternating manner. The pre-charge period is repeated periodically. The pre-charge idle period corresponds to a idle period between pre-charge intervals. The pre-charge cooling section is performed after the completion of the pre-charge section and the pre-charge idling section.

As shown in the figure, the precharge period is a period in which the precharge relay 130 is turned on, and the precharge period and the precharge period are periods in which the precharge relay 130 is turned off. Accordingly, the precharge cycle may be performed as the control unit 150 controls the precharge relay 130. That is, the controller 150 may perform the precharge cycle by adjusting the opening and closing of the precharge relay 130 to correspond to each section.

More specifically, in the embodiment of Fig. 3, the precharge period is performed three times, and the precharge period is also performed three times. And, the time at which one pre-charge interval is performed is t _precharge . That is, the _{precharge period} is t _precharge . Similarly, the time at which one pre-charge idle period is performed is t _interval , and the size of the pre-charge idle period is t _interval .

Also, in the embodiment of FIG. 3, the pre-charge interval and the pre-charge idle interval are repeated three times each, and then the pre-charge cooling interval is performed. The time during which the precharge cooling section is performed is t _cooldown , and the size of the precharge cooling section is t _cooldown .

Hereinafter, the temperature change process of the precharge resistance will be described with reference to the precharge cycle shown in FIG.

Prior to the description, the temperature rise coefficient and the cooling coefficient of the pre-charge resistance applied to the pre-charge system 100 are denoted by a and b, respectively, and the operating temperature at which the precharge system 100 operates is denoted by T _normal . The operating temperature at which the precharge system 100 operates may be the temperature of the surrounding environment or the rated temperature of the system to which the precharge system 100 is applied (for example, an electric vehicle). The threshold temperature is denoted by T _threshold . The threshold temperature is the upper temperature limit associated with precharge resistor 140 applied to precharge system 100. The critical temperature means a temperature value at which a predetermined margin is considered in a maximum temperature value or a maximum temperature value at which the precharge resistor 140 can operate normally. The threshold temperature may be set differently according to the pre-charge resistance 140, and may be predetermined through experimentation, simulation, or the like.

First, the temperature changes after the pre-charge interval and the pre-charge idle interval are repeated three times are as follows.

The temperature change when the pre-charge interval and the pre-charge idle interval are repeated three times is determined by the temperature increase due to three pre-charge intervals and the temperature decrease due to cooling by the three pre-charge idle periods. Therefore, the temperature of the pre-charge resistance after the pre-charge interval and the pre-charge idle interval are repeated three times can be expressed by the following equation.

Here, T ₁ is the temperature of the pre-charge resistance after the pre-charge interval and the pre-charge idle period are repeated three times, T _normal is the operating temperature or operating temperature, a is the temperature rise coefficient of the pre- The pre-charge resistance cooling coefficient, t _precharge, is the size of the pre-charge interval, and t _interval is the size of the pre-charge idle interval.

Next, the temperature changes when the pre-charge interval and the pre-charge idle interval are repeated three times and the pre-charge cooling interval is performed are as follows.

After the pre-charge interval and the pre-charge idle period are repeated three times, the temperature change when the pre-charge cooling interval is performed is the temperature increase by three pre-charge intervals, the temperature decrease by three pre- And is determined by the temperature decrease due to the pre-charge cooling section. Therefore, the temperature of the pre-charge resistance when the pre-charge interval and the pre-charge idle period are repeated three times and then the pre-charge cooling interval is performed can be expressed by the following equation.

Here, T _2, the pre-charging period and the precharge idle period is repeated three times and then, the temperature after the pre-charge cooling interval is performed precharge resistance, T ₁ is the pre-charging period and the precharge idle period three times the temperature of the pre-repeat after the charge resistance, T _normal, the operating temperature or operating temperature, a is, the temperature rising coefficient of the pre-charging resistor, b, the cooling coefficient of the pre-charging resistor, t _precharge, the precharge interval size, t _interval is the size of the pre-charge idle period, and t _cooldown is the size of the pre-charge cooling period.

Equations (1) and (2) are derived from the case where the pre-charge interval and the pre-charge idle interval are alternately repeated three times. If the equations (1) and (2) are generalized, same.

Here, T ₁ is the temperature of the pre-charge resistance after the pre-charge interval and the pre-charge idling interval are repeated n times, T _normal is the operating temperature or rated temperature, a is the temperature rise coefficient of the pre- The pre-charge resistance cooling coefficient, t _precharge, is the size of the pre-charge interval, and t _interval is the size of the pre-charge idle interval.

Here, T ₂ is the temperature of the pre-charge resistance after the pre-charge interval and the pre-charge idle period are repeated n times, the temperature of the pre-charge resistance after the pre-charge cooling interval is performed, and T ₁ is the pre- the temperature of the pre-repeat after the charge resistance, T _normal, the operating temperature or operating temperature, a is, the temperature rising coefficient of the pre-charging resistor, b, the cooling coefficient of the pre-charging resistor, t _precharge, the precharge interval size, t _interval is the size of the pre-charge idle period, and t _cooldown is the size of the pre-charge cooling period.

The above description relates to the temperature change of the pre-charge resistance during the execution of the pre-charge cycle. Hereinafter, the process of determining the algorithm for the pre-charge cycle will be described.

The control unit 150 is configured to perform a precharge cycle and a precharge cycle period by repeating the precharge cycle and the precharge cycle period according to the above description, and to perform the precharge cycle after the precharge cycle and the precharge cycle period are completed.

In carrying out the pre-charge cycle, the parameters to be determined are as follows.

n: number of repetitions of pre-charge interval and pre-charge idle interval

t _precharge : Size of precharge section

t _interval : the size of the pre-charge idle interval

t _cooldown : Size of pre-charge cooling section

T _normal : Operating temperature

T _threshold : critical temperature

a: Temperature rise coefficient of pre-charge resistance

b: cooling coefficient of pre-charge resistance

Here, the operating temperature, the critical temperature, the temperature rise coefficient of the pre-charge resistance, and the cooling coefficient of the pre-charge resistance are treated as constants. Also, since the size of the precharge section is determined by the apparatus to which the battery 10 is to be applied, the size of the precharge section is also treated as a constant. That is, the operation temperature, the threshold temperature, the temperature rise coefficient of the precharge resistance, the cooling coefficient of the precharge resistance, and the size of the precharge section may be predetermined and stored in a memory device or the like. However, it is to be understood that the operating temperature and the like are treated as constants, and it is not excluded that they can be used as input variables to the control unit 150. [

Finally, the parameters to be determined are the pre-charge interval and the number of repetitions n of the pre-charge idle period, the size of the pre-charge idle period t _interval , and the size of the pre-charge cooling period t _cooldown .

If the parameter is determined, the controller 150 may repeat the pre-charge interval and the pre-charge idle interval based on the determined parameter, and then perform the pre-charge cooling interval.

According to one embodiment, the control unit 150 determines three parameters (n, t _interval , t _cooldown ) based on k. Here, k represents a change amount of the temperature of the pre-charge resistance that changes as the pre-charge period and the pre-charge idle period are crossed once and a change amount of the temperature change amount of the pre- It means rain.

That is, k can be expressed by the following equation.

Here, T _pi is the amount of change in the temperature of the pre-charge resistor that changes as the pre-charge interval and the pre-charge idle period are crossed once, and T _p is the change amount of the precharge transition period Is the amount of change in the temperature of the pre-charge resistor.

Also, it is preferable that the temperature change of the pre-charge resistance varies as the pre-charge interval and the pre-charge idle interval are crossed once, and the temperature of the pre-charge resistance changes as the pre-charge interval and the pre- Can be expressed by the following equation.

Substituting Equation (6) and Equation (7) into Equation (5), the following mathematical expression is derived.

This is summarized as follows for a and b.

Referring again to Equation (3), the following Equation 3 is obtained.

&Quot; (3) "

Here, assuming that the current temperature has reached the critical temperature, Equation (3) can be expressed by the following equation.

When substituted into the equation (9) or equation (10) in equation (11), organized for the _precharge t, it can be expressed as the following mathematical expression of.

The above equation (12) can be summarized as follows.

Therefore, by using the equation (13), n can be obtained. That is, the number of repetitions of the pre-charge interval and the pre-charge idle interval can be obtained.

Further, by substituting the equation 9 or the equation 10 in equation 11, summarized for the _interval t, it may be expressed as the following mathematical expression of.

Substituting Equation (13) into Equation (14), the following equation is derived.

Therefore, using equation (15), t _interval can be obtained. That is, the size of the pre-charge idle period can be obtained.

Using Equations (13) and (15), it is possible to derive the number of repetitions of the pre-charge period, the pre-charge idle period, and the size of the pre-charge idle period. In other words, using equations (13) and (15), parameters for performing the pre-charge cycle before the pre-charge cooling period can be derived. Since the number of repetitions of the pre-charge interval and the pre-charge idle interval must be a natural number, when the number n derived from Equation (13) is not a natural number, the controller 150 increments, rounds, To a natural number. Preferably, the control unit 150 is configured to convert n to a natural number by truncating below the decimal point. This is because, if n is rounded up or rounded down below the decimal point, the pre-charge temperature may exceed the threshold temperature if n pre-charge periods and pre-charge idle periods are repeated.

Next, the process of deriving the size (t _cooldown ) of the pre-charge cooling section will be described.

The size of the pre-charge cooling period is determined according to the temperature of the pre-charge resistance after n pre-charge periods and pre-charge idle periods are performed. This is because the pre-charge cooling section cools the pre-charge resistance close to the critical temperature to the operating temperature. Since the temperature of the pre-charge resistance is substantially equal to the threshold temperature after n pre-charge periods and pre-charge idle periods are performed, after n pre-charge periods and pre-charge idle periods are performed, The temperature can be approximated to a critical temperature. Accordingly, the controller 150 can determine the size of the pre-charge cooling section using the following equation.

Where T _threshold is the critical temperature, T _normal is the operating temperature, b is the cooling coefficient of the pre-charge resistance, t _cooldown is the size of the pre-

Thus, using the equation (16), the size of the pre-charge cooling section can be derived.

Consequently, using Equations (13), (15), and (16), it is possible to determine all the parameters required to perform the pre-charge cycle. Accordingly, the controller 150 can determine the parameters required to perform the pre-charge cycle using the above-described equation, and can perform the pre-charge cycle using the determined parameters.

According to another aspect of the present invention, the precharge system described above may be included in the charging system. As described above, the precharge system can constitute a part of the charging system.

According to another aspect of the present invention, the precharge system described above may be included in a battery pack. That is, the battery pack according to another aspect of the present invention may include the precharge system described above. At this time, the precharge system may be included in the charging system and included in the battery pack.

According to another aspect of the present invention, the above-described precharge system can be included in an automobile. That is, the automobile according to another aspect of the present invention may include the precharge system described above. On the other hand, the automobile includes an electric vehicle or a hybrid vehicle, which is a means of transportation using electric energy as a power source, and a vehicle equipped with electrical equipment supplied with electric power from electric energy.

Hereinafter, a precharge method according to another aspect of the present invention will be described. As for the precharge method according to another aspect of the present invention, the description of the precharge system as described above can be applied as it is, and repetitive description thereof will be omitted.

The precharge method according to another aspect of the present invention may use the precharge system described above, and the subject of each step of performing the method may be each component of the precharge system.

4 is a flowchart illustrating a precharge method according to an embodiment of the present invention.

4, a precharge method according to an embodiment of the present invention includes a precharge relay 130 connected in parallel with a main relay 110, a precharge relay 130 connected in series with a precharge relay 130, The preprocessing system 100 is prepared (step S410). Next, the method performs a pre-charging step of alternately repeating turn-on and turn-off of the pre-charge relay 130 so that a pre-charge idle period, which is a idle period between the pre-charge period and the pre- (S440). Here, the pre-charge period and the pre-charge idle period are alternately repeated until the temperature of the pre-charge resistor reaches the threshold temperature in the pre-charge step S440.

After the precharge step S440, the method performs a cooling step of turning off the precharge relay 130 so that the precharge resistor 140 is cooled (S450).

On the other hand, the method can perform the pre-charge cycle according to the above-mentioned steps, but can determine the operation algorithm for performing the pre-difference cycle in advance.

That is, before the pre-charge step, the pre-charge period and the pre-charge period are repeated such that the pre-charge period and the pre-charge idle period are alternately repeated until the temperature of the pre-charge resistor reaches the threshold temperature, And determining the number of repetitions of the interval and the size of the pre-charge pause interval (S420). In this case, the pre-charge step S440 may include the pre-charge relay 130, the pre-charge relay 130, and the pre-charge relay 130, depending on the number of repetitions of the pre-charge interval, ) Can be alternately repeated.

According to one embodiment, the determining step may include a step of determining a change amount of the temperature of the pre-charge resistance that changes as one pre-charge period and a pre-charge idle period are cross- The size of the pre-charge idle period and the number of times the pre-charge idle period is repeated may be determined so as to be k times the variation amount of the temperature of the resistor.

In this case, the determining step may determine the size of the precharge hibernation period and the number of repetitions of the precharge period and the precharge hibernation period using the previously derived equations (13) and (15).

Here, n is the number of iterations, T _threshold is the critical temperature of the pre-charging period and the precharge idle period, T _normal is the operating temperature, a temperature rising coefficient of the pre-charging resistor, b is the cooling coefficient of the pre-charging resistor, t _precharge is Size of pre-charge interval

According to one embodiment, the method further comprises, after the determining, determining (S430) the size of the precharge cooling section such that the precharge resistor 140 is cooled to reach the operating temperature The cooling step S450 may be a step of turning off the precharge relay 130 according to the size of the precharge cooling interval determined in the step S430 of determining the size of the precharge cooling interval have.

In the step of determining the size of the pre-charge cooling interval (S430), the size of the pre-charge cooling interval may be determined using Equation (16).

Where T _threshold is the critical temperature, T _normal is the operating temperature, b is the cooling coefficient of the pre-charge resistance, t _cooldown is the size of the pre-

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not to be limited to the details thereof and that various changes and modifications will be apparent to those skilled in the art. And various modifications and variations are possible within the scope of the appended claims.

The features described in the individual embodiments herein may be combined and implemented in a single embodiment. Conversely, various features described herein in a single embodiment may be implemented in various embodiments individually or in a suitable subcombination.

10: Battery
20: load 21: inverter 22: motor
30: Charging system 100: Precharge system
110: main relay 120: ground relay
130: pre-charge relay 140: pre-charge resistance
150:

Claims (20)

In the precharge system,
A precharge relay connected in parallel with the main relay;
A precharge resistor connected in series with the precharge relay; And
A precharge cycle in which a precharge cycle period that is periodically repeated, a precharge cycle period that is a idle period between the precharge cycles, and a precharge cycle that is a period after the precharge cycle and the precharge cycle period form one cycle And a controller,
Wherein,
Charging resistance is changed so that the amount of change of the temperature of the pre-charging resistance that varies as one pre-charge period and the pre-charge idling period are crossed is k times the amount of change of the temperature of the pre- The size of the pre-charge idle period, the number of repetitions of the pre-charge period and the pre-charge idle period are determined using Equation (1)
[Equation 1]

And repeatedly repeats the precharge period and the precharge period until the temperature of the precharge resistor reaches the threshold temperature,
In Equation 1, n is the number of iterations, T _threshold is the critical temperature, T _normal is the operating temperature, a temperature rising coefficient of the pre-charging resistor, b is the cooling coefficient of the pre-charging resistor, t _precharge is the Wherein the precharge period is a size of the precharge period, and the period _tinterval is a period of the precharge period.
delete delete delete The method according to claim 1,
Wherein the size of the precharge section is a preset value or a value received from the outside by the control section.
The method according to claim 1,
Wherein the control unit receives the value of k from the outside.
The method of claim 6,
The control unit determines the size of the pre-charge cooling interval so that the pre-charge resistance is cooled during the pre-charge cooling interval to reach the operating temperature,
Wherein the controller performs the pre-charge cycle according to the determined size of the pre-charge cooling section.
The method of claim 7,
The controller determines the size of the pre-charge cooling section by using Equation (2) below,
&Quot; (2) "

_Wherein T _threshold is the critical temperature, T _normal is the operating temperature, b is the cooling coefficient of the pre-charge resistance, and t _cooldown is the size of the pre-charge cooling period.
The method according to claim 1,
Wherein the precharge period is a period during which the precharge relay is turned on, and the precharge period and the precharge period are periods during which the precharge relay is turned off.
A charging system comprising a pre-charging system according to any of claims 1 and 5 to 9.
A battery pack comprising a precharge system according to any one of claims 1 to 9.
A car comprising a pre-charging system according to any of claims 1 and 5 to 9.
A precharging method using a precharge system including a precharge relay connected in parallel to a main relay and a precharge resistor connected in series with the precharge relay,
A precharge transition period which is a transition period between one precharge transition period and a precharge transition period between a precharge transition period and a precharge transition period, Determining the number of repetitions of the pre-charge interval, the pre-charge idle interval, and the size of the pre-charge idle interval so that the temperature becomes k times the change amount of the temperature of the pre-charge interval;
A precharge step of alternately repeating the turn-on and turn-off of the precharge relay such that the precharge section and the precharge break section are repeatedly crossed by the determined number of times until the temperature of the precharge resistor reaches the threshold temperature ; And
And a cooling step of turning off the precharge relay so that the precharge resistor is cooled after the precharge step,
The precharge step may be configured to repeatedly repeat the precharge period and the precharge period until the temperature of the precharge resistance, which is changed as the precharge period and the precharge period are repeated, And,
[Equation 1]

In Equation 1, n is the number of iterations, T _threshold is the critical temperature, T _normal is the operating temperature, a temperature rising coefficient of the pre-charging resistor, b is the cooling coefficient of the pre-charging resistor, t _precharge is the The size of the pre-charge _interval , and t _interval is the size of the pre-charge idle interval,
delete delete delete 14. The method of claim 13,
Wherein the size of the precharge section is a preset value or an input value before the determining step.
14. The method of claim 13,
Characterized in that the method further comprises the step of receiving the value of k from the outside before said determining step.
19. The method of claim 18,
The method may further comprise, after the determining, determining the size of the precharge cooling section such that the precharge resistor is cooled to reach the operating temperature,
Wherein the cooling step is a step of turning off the precharge relay according to the size of the precharge cooling section determined in the step of determining the size of the precharge cooling section.
The method of claim 19,
Wherein the step of determining the size of the pre-charge cooling section determines a size of the pre-charge cooling section using Equation (2) below,
&Quot; (2) "

_Wherein T _threshold is the critical temperature, T _normal is the operating temperature, b is the cooling coefficient of the pre-charge resistance, and t _cooldown is the size of the pre-charge cooling period.

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