CN103368235A - Nickel-metal hydride battery charge-discharge circuit in uninterruptible power supply - Google Patents

Abstract

Translated fromChinese

一种不间断电源内的镍氢电池充放电电路，它包括充电器、放电二极管和充放电控制电路，所述充放电控制电路包括单片机、充电继电器和充电MOS管，所述充电器经充电继电器的常开触点给镍氢电池充电并经充电继电器的常闭触点接不间断电源直流升压的输入端，其控制信号输入端接单片机的输出端口；所述充电MOS管控制充电继电器控制线圈，其栅极接单片机的输出端口；镍氢电池的输出电压经第一电阻和第二电阻分压后接单片机的电压采样端口，第三电阻串接在镍氢电池负极与充电器输出地之间，其输出信号接单片机的电流采样端口；镍氢电池经放电二极管给逆变器供电。本发明大大减少了充电频次，从而延长了镍氢电池使用寿命，降低了不间断电源的运行和维护成本。

A nickel-metal hydride battery charge and discharge circuit in an uninterruptible power supply, which includes a charger, a discharge diode and a charge and discharge control circuit, the charge and discharge control circuit includes a single-chip microcomputer, a charging relay and a charging MOS tube, and the charger is charged through the charging relay The normally open contact of the charging relay charges the Ni-MH battery and is connected to the input terminal of the uninterruptible power supply DC boost through the normally closed contact of the charging relay, and its control signal input terminal is connected to the output port of the single-chip microcomputer; the charging MOS tube controls the charging relay control Coil, the gate of which is connected to the output port of the single-chip microcomputer; the output voltage of the nickel-metal hydride battery is divided by the first resistor and the second resistor and then connected to the voltage sampling port of the single-chip microcomputer, and the third resistor is connected in series between the negative pole of the nickel-hydrogen battery and the output ground of the charger Between, the output signal is connected to the current sampling port of the microcontroller; the nickel metal hydride battery supplies power to the inverter through the discharge diode. The invention greatly reduces the frequency of charging, thereby prolonging the service life of the nickel-metal hydride battery and reducing the operation and maintenance costs of the uninterruptible power supply.

Description

Translated fromChinese

一种不间断电源内的镍氢电池充放电电路A Ni-MH battery charging and discharging circuit in an uninterruptible power supply

技术领域technical field

本发明涉及一种可防止不间断电源内部镍氢电池频繁充放电的电池充电电路，属电源技术领域。The invention relates to a battery charging circuit capable of preventing frequent charging and discharging of nickel-metal hydride batteries inside an uninterruptible power supply, belonging to the technical field of power supplies.

背景技术Background technique

由于铅酸电池与锂电池不能在低温条件下大电流放电，因此工作于低温环境中的不间断电源一般需选用镍氢电池。镍氢电池的充电方式与铅酸电池和锂电池的不同，不能长时间浮充充电，只能采用恒流充电方式。现有不间断电源的恒流充电器将电池充满电后就会停止工作，但为实现不间断电源的在线零切换功能，镍氢电池一直保持热备份状态，也就是说镍氢电池充满电后一直处于小电流放电状态，致使镍氢电池的充电周期缩短，充电频次增加，大大降低了镍氢电池的使用寿命，提高了不间断电源的运行和维护成本。Since lead-acid batteries and lithium batteries cannot be discharged at high currents at low temperatures, nickel-metal hydride batteries are generally required for uninterruptible power supplies that work in low-temperature environments. The charging method of Ni-MH batteries is different from that of lead-acid batteries and lithium batteries. It cannot be floated and charged for a long time, and can only be charged by constant current. The current constant current charger of the uninterruptible power supply will stop working after the battery is fully charged. It has been in a low current discharge state, which shortens the charging cycle of the Ni-MH battery and increases the charging frequency, which greatly reduces the service life of the Ni-MH battery and increases the operation and maintenance costs of the uninterruptible power supply.

发明内容Contents of the invention

本发明的目的在于针对现有技术之弊端，提供一种不间断电源内部镍氢电池充电电路，以延长镍氢电池的使用寿命，降低不间断电源的运行和维护成本。The object of the present invention is to aim at the drawbacks of the prior art, and provide an internal Ni-MH battery charging circuit of the UPS to prolong the service life of the Ni-MH battery and reduce the operation and maintenance costs of the UPS.

本发明所述问题是以下述技术方案实现的：Problem described in the present invention is realized with following technical scheme:

一种不间断电源内的镍氢电池充放电电路，构成中包括充电器、放电二极管和充放电控制电路，所述充放电控制电路包括单片机、充电继电器、充电MOS管和三个电阻，所述充电器经充电继电器的常开触点给镍氢电池充电并经充电继电器的常闭触点接不间断电源的直流升压输入端，其控制信号输入端接单片机的输出端口；所述充电MOS管控制充电继电器控制线圈，其栅极接单片机的输出端口；镍氢电池的输出电压经第一电阻和第二电阻分压后接单片机的电压采样端口，第三电阻串接在镍氢电池负极与充电器输出地之间，其输出信号经过放大器接单片机的电流采样端口；镍氢电池经放电二极管给不间断电源的直流升压电路供电。A nickel-metal hydride battery charging and discharging circuit in an uninterruptible power supply, comprising a charger, a discharging diode and a charging and discharging control circuit, the charging and discharging control circuit including a single-chip microcomputer, a charging relay, a charging MOS tube and three resistors, the The charger charges the Ni-MH battery through the normally open contact of the charging relay and is connected to the DC boost input terminal of the uninterruptible power supply through the normally closed contact of the charging relay, and its control signal input terminal is connected to the output port of the single-chip microcomputer; the charging MOS The tube controls the charging relay control coil, and its gate is connected to the output port of the single-chip microcomputer; the output voltage of the nickel-metal hydride battery is divided by the first resistor and the second resistor and then connected to the voltage sampling port of the single-chip microcomputer, and the third resistor is connected in series to the negative pole of the nickel-hydrogen battery Between the charger and the output ground, the output signal is connected to the current sampling port of the single-chip microcomputer through the amplifier; the Ni-MH battery supplies power to the DC boost circuit of the uninterruptible power supply through the discharge diode.

上述不间断电源内的镍氢电池充放电电路，构成中还包括放电继电器、放电MOS管和直流接触器，所述放电继电器的常开触点与直流接触器的控制线圈串接后接于镍氢电池两端，所述放电MOS管控制放电继电器的控制线圈，其栅极接单片机的输出端口；所述直流接触器的常开触点并接在放电二极管上。The Ni-MH battery charging and discharging circuit in the above-mentioned uninterruptible power supply also includes a discharge relay, a discharge MOS tube and a DC contactor in the composition, and the normally open contact of the discharge relay is connected in series with the control coil of the DC contactor and then connected to the nickel At both ends of the hydrogen battery, the discharge MOS tube controls the control coil of the discharge relay, and its gate is connected to the output port of the single-chip microcomputer; the normally open contact of the DC contactor is also connected to the discharge diode.

上述不间断电源内的镍氢电池充放电电路，所述充电器包括整流桥、开关管、变压器、整流二极管和PWM隔离驱动电路，所述开关管与变压器的原边线圈串联连接后接整流桥输出的直流电压，所述PWM隔离驱动电路的输入端接单片机的输出端口，其输出端接开关管的栅极；所述变压器的副边线圈一端接充电器输出地，一端经整流二极管接充电继电器的公共触点。The Ni-MH battery charging and discharging circuit in the above-mentioned uninterruptible power supply, the charger includes a rectifier bridge, a switch tube, a transformer, a rectifier diode and a PWM isolation drive circuit, and the switch tube is connected in series with the primary coil of the transformer and then connected to the rectifier bridge The output DC voltage, the input terminal of the PWM isolation drive circuit is connected to the output port of the single chip microcomputer, and the output terminal is connected to the gate of the switch tube; one end of the secondary coil of the transformer is connected to the output ground of the charger, and one end is connected to the charging port through the rectifier diode Common contact of the relay.

上述不间断电源内的镍氢电池充放电电路，所述充放电控制电路由DC/DC辅助电源供电，所述辅助电源的输入端接不间断电源的直流输入端。For the Ni-MH battery charge and discharge circuit in the uninterruptible power supply, the charge and discharge control circuit is powered by a DC/DC auxiliary power supply, and the input terminal of the auxiliary power supply is connected to the DC input terminal of the uninterruptible power supply.

上述不间断电源内的镍氢电池充放电电路，所述充电继电器和放电继电器的控制线圈上均并接有续流二极管。In the charging and discharging circuit of the Ni-MH battery in the above-mentioned uninterruptible power supply, the control coils of the charging relay and the discharging relay are all connected in parallel with freewheeling diodes.

上述不间断电源内的镍氢电池充放电电路，在镍氢电池的放电回路中串接有熔断器。The charging and discharging circuit of the Ni-MH battery in the above-mentioned uninterruptible power supply has a fuse connected in series in the discharge circuit of the Ni-MH battery.

本发明的充放电控制电路可对镍氢电池的电压进行实时监测，当电池充电完成后，将充电器输出端切换到不间断电源的直流升压输入端，由充电器为不间断电源提供热备份所需能耗；当镍氢电池因自放电导致电池电压降低时，容量随之减少，单片机程序根据镍氢电池的采样电压，计算出电池容量，当镍氢电池容量降到额定值的80%时，充放电控制电路再将充电器输出端切换至镍氢电池，开始给镍氢电池充电。由于镍氢电池在充满电后不用提供热备份能量，大大降低了电池的放电速度，减少了充电频次，从而延长了镍氢电池的使用寿命，降低了不间断电源的运行和维护成本。此外，本发明还具有电路结构简单、成本低廉、可靠性高等优点。The charging and discharging control circuit of the present invention can monitor the voltage of the nickel-metal hydride battery in real time. When the battery is charged, the output terminal of the charger is switched to the DC boost input terminal of the uninterruptible power supply, and the charger provides heat for the uninterruptible power supply. Energy consumption required for backup; when the battery voltage drops due to self-discharge of the Ni-MH battery, the capacity will decrease accordingly, and the single-chip computer program calculates the battery capacity according to the sampling voltage of the Ni-MH battery. %, the charge and discharge control circuit switches the output of the charger to the Ni-MH battery and starts charging the Ni-MH battery. Since the Ni-MH battery does not need to provide thermal backup energy after it is fully charged, the discharge speed of the battery is greatly reduced and the frequency of charging is reduced, thereby prolonging the service life of the Ni-MH battery and reducing the operation and maintenance costs of the UPS. In addition, the invention also has the advantages of simple circuit structure, low cost and high reliability.

附图说明Description of drawings

下面结合附图对本发明作进一步说明。The present invention will be further described below in conjunction with accompanying drawing.

图1为本发明的电原理图。Fig. 1 is the electrical schematic diagram of the present invention.

图中各标号清单为：B、镍氢电池；U1、单片机； U2、PWM隔离驱动；ZQ、整流桥；DC/DC、辅助电源；T、变压器；NB、不间断电源直流升压；K1、放电继电器；K2、充电继电器；   K3、直流接触器；D1、第一续流二极管；D2、第二续流二极管；D3、放电二极管；D4、整流二极管；T1、放电MOS管；T2、充电MOS管；T3、开关管； R1～R3、第一电阻～第三电阻；FU、熔断器。The list of labels in the figure is: B, Ni-MH battery; U1, single-chip microcomputer; U2, PWM isolation drive; ZQ, rectifier bridge; DC/DC, auxiliary power supply; T, transformer; NB, uninterruptible power supply DC boost; K1, Discharging relay; K2, charging relay; K3, DC contactor; D1, first freewheeling diode; D2, second freewheeling diode; D3, discharging diode; D4, rectifying diode; T1, discharging MOS tube; T2, charging MOS Tube; T3, switch tube; R1 ~ R3, the first resistor to the third resistor; FU, fuse.

具体实施方式Detailed ways

参看图1，本发明由充电器、放电二极管、辅助电源和充放电控制电路组成。其中充电器由PWM隔离驱动U2、整流桥ZQ、变压器T、整流二极管D4和开关管T3组成；充放电控制电路由单片机U1、放电继电器K1、充电继电器K2、直流接触器K3、第一续流二极管D1、第二续流二极管D2、放电二极管D3、放电MOS管T1、充电MOS管T2、第一电阻R1～第三电阻R3和熔断器FU组成，辅助电源为充放电控制电路供电。Referring to Fig. 1, the present invention is made up of charger, discharge diode, auxiliary power supply and charge and discharge control circuit. The charger is composed of PWM isolation driver U2, rectifier bridge ZQ, transformer T, rectifier diode D4 and switch tube T3; the charge and discharge control circuit is composed of single-chip microcomputer U1, discharge relay K1, charge relay K2, DC contactor K3, the first freewheeling circuit The diode D1, the second freewheeling diode D2, the discharge diode D3, the discharge MOS transistor T1, the charge MOS transistor T2, the first resistor R1 to the third resistor R3 and the fuse FU are composed, and the auxiliary power supply supplies power for the charge and discharge control circuit.

该电路的工作原理如下：The circuit works as follows:

单片机U1通过第一电阻R1和第二电阻R2组成的分压电路监测镍氢电池B的端电压，判断镍氢电池B是否需要充电，通过第三电阻R3监测镍氢电池B的充电电流，并控制恒流充电器的输出电流。当镍氢电池B被监测到充满电时，单片机U1的P1.3端口给出低电平信号，该信号送至放电MOS管T1的栅极，放电MOS管T1截止，使放电继电器K1断开，放电继电器K1断开后，直流接触器K3断开；与此同时，单片机U1的P1.4端口也给出的低电平信号，该信号送至充电MOS管T2的栅极，充电MOS管T2截止，充电继电器K2的常开触点断开，常闭触点闭合，使充电器的输出端连接在不间断电源的直流升压NB的输入端，同时，控制程序将充电器的输出电压稳定在最高充电电压上，此时充电器输出电压≥镍氢电池B的端电压，即放电二极管D3的阴极电压≥其阳极电压，镍氢电池B不会向外放电，电池也不会被充电。此时，直流输入热备份所需功率完全由充电器提供。The single-chip microcomputer U1 monitors the terminal voltage of the Ni-MH battery B through the voltage divider circuit composed of the first resistor R1 and the second resistor R2, judges whether the Ni-MH battery B needs to be charged, monitors the charging current of the Ni-MH battery B through the third resistor R3, and Controls the output current of the constant current charger. When the Ni-MH battery B is detected to be fully charged, the P1.3 port of the microcontroller U1 gives a low-level signal, which is sent to the gate of the discharge MOS transistor T1, and the discharge MOS transistor T1 is cut off, so that the discharge relay K1 is disconnected , after the discharge relay K1 is disconnected, the DC contactor K3 is disconnected; at the same time, the P1.4 port of the microcontroller U1 also gives a low-level signal, which is sent to the gate of the charging MOS tube T2, and the charging MOS tube T2 cuts off, the normally open contact of the charging relay K2 is disconnected, and the normally closed contact is closed, so that the output terminal of the charger is connected to the input terminal of the DC boost NB of the uninterruptible power supply. At the same time, the control program converts the output voltage of the charger to Stable at the highest charging voltage. At this time, the output voltage of the charger ≥ the terminal voltage of the Ni-MH battery B, that is, the cathode voltage of the discharge diode D3 ≥ its anode voltage, the Ni-MH battery B will not be discharged, and the battery will not be charged. . At this time, the power required by the DC input hot backup is completely provided by the charger.

当不间断电源的交流输入出现异常时，充电器输出电压V+迅速降低，当镍氢电池B的端电压≥放电二极管D3的导通压降+充电器输出电压V+时，不间断电源直流升压NB的输入由镍氢电池B通过放电二极管D3供电，实现不间断电源零切换功能。与此同时，单片机U1的P1.3端口给出高电平信号，该信号送至放电MOS管T1的栅极，放电MOS管T1导通，进而导致放电继电器K1吸合，放电继电器K1吸合后，直流接触器K3吸合，放电二极管D3被直流接触器K3短路，保证放电二极管D3不长时间工作，减少了能量的损耗。整个过程中Vin+不会低于电池欠压电压，辅助电源工作稳定正常。When the AC input of the uninterruptible power supply is abnormal, the output voltage V+ of the charger will drop rapidly. The input of NB is powered by Ni-MH battery B through discharge diode D3, realizing the zero switching function of uninterruptible power supply. At the same time, the P1.3 port of the single-chip microcomputer U1 gives a high-level signal, which is sent to the gate of the discharge MOS transistor T1, and the discharge MOS transistor T1 is turned on, thereby causing the discharge relay K1 to pull in, and the discharge relay K1 to pull in Finally, the DC contactor K3 pulls in, and the discharge diode D3 is short-circuited by the DC contactor K3, ensuring that the discharge diode D3 does not work for a long time and reduces energy loss. During the whole process, Vin+ will not be lower than the battery undervoltage voltage, and the auxiliary power supply works stably and normally.

当镍氢电池B的电压被检测到过低时，不间断电源直流升压NB欠压保护，不再消耗电池电量。当交流输入恢复正常时，单片机U1将其P1.4端口的输出信号调整为高电平，该电平送至充电MOS管T2栅极，充电MOS管T2导通，充电继电器K2吸合，使V+连接在镍氢电池B的正极，开始给镍氢电池B充电。此时单片机U1的P1.3端口为低电平，直流接触器K3断开，充电器为电池充电的同时通过二极管D3为不间断电源直流升压NB提供热备份直流电源。When the voltage of Ni-MH battery B is detected to be too low, the uninterruptible power supply DC boost NB undervoltage protection will no longer consume battery power. When the AC input returns to normal, the single-chip microcomputer U1 adjusts the output signal of its P1. V+ is connected to the positive pole of Ni-MH battery B, and starts to charge Ni-MH battery B. At this time, the P1.3 port of the single chip microcomputer U1 is at low level, the DC contactor K3 is disconnected, and the charger is charging the battery while providing hot backup DC power for the uninterruptible power supply DC boost NB through the diode D3.

熔断器FU在电路中的作用是保护镍氢电池B和直流电路；第一续流二极管D1和第二续流二极管D2的作用为减缓浪涌电压扰动。The role of the fuse FU in the circuit is to protect the Ni-MH battery B and the DC circuit; the role of the first freewheeling diode D1 and the second freewheeling diode D2 is to slow down the surge voltage disturbance.

Claims (6)

Translated fromChinese

1.一种不间断电源内的镍氢电池充放电电路，其特征是，所述电路包括充电器、放电二极管（D3）和充放电控制电路，所述充放电控制电路包括单片机（U1）、充电继电器（K2）和充电MOS管（T2），所述充电器经充电继电器（K2）的常开触点给镍氢电池（B）充电并经充电继电器（K2）的常闭触点接不间断电源直流升压（NB）的输入端；所述充电MOS管（T2）控制充电继电器（K2）控制线圈，其栅极接单片机（U1）的输出端口；镍氢电池（B）的输出电压经第一电阻（R1）和第二电阻（R2）分压后接单片机（U1）的电压采样端口，第三电阻（R3）串接在镍氢电池（B）负极与充电器输出地之间，其输出信号接单片机（U1）的电流采样端口；镍氢电池（B）经放电二极管（D3）给不间断电源的直流升压（NB）供电。1. A Ni-MH battery charge and discharge circuit in an uninterruptible power supply, characterized in that the circuit includes a charger, a discharge diode (D3) and a charge and discharge control circuit, and the charge and discharge control circuit includes a single-chip microcomputer (U1), Charging relay (K2) and charging MOS tube (T2), the charger charges the Ni-MH battery (B) through the normally open contact of the charging relay (K2) and is not connected through the normally closed contact of the charging relay (K2). The input terminal of the DC boost (NB) of the intermittent power supply; the charging MOS tube (T2) controls the charging relay (K2) control coil, and its gate is connected to the output port of the single-chip microcomputer (U1); the output voltage of the Ni-MH battery (B) After the voltage is divided by the first resistor (R1) and the second resistor (R2), it is connected to the voltage sampling port of the microcontroller (U1), and the third resistor (R3) is connected in series between the negative pole of the Ni-MH battery (B) and the output ground of the charger. , whose output signal is connected to the current sampling port of the single-chip microcomputer (U1); the nickel-metal hydride battery (B) supplies power to the DC boost (NB) of the uninterruptible power supply through the discharge diode (D3).2.根据权利要求1所述的一种不间断电源内的镍氢电池充放电电路，其特征是，构成中还包括放电继电器（K1）、放电MOS管（T1）和直流接触器（K3），所述放电继电器（K1）的常开触点与直流接触器（K3）的控制线圈串接后接于镍氢电池（B）两端，所述放电MOS管（T1）控制放电继电器（K1）的控制线圈，其栅极接单片机（U1）的输出端口；所述直流接触器（K3）的常开触点并接在放电二极管（D3）上。2. A Ni-MH battery charge and discharge circuit in an uninterruptible power supply according to claim 1, characterized in that the composition also includes a discharge relay (K1), a discharge MOS tube (T1) and a DC contactor (K3) , the normally open contact of the discharge relay (K1) is connected in series with the control coil of the DC contactor (K3) and then connected to both ends of the Ni-MH battery (B), and the discharge MOS tube (T1) controls the discharge relay (K1 ) of the control coil, the gate of which is connected to the output port of the microcontroller (U1); the normally open contact of the DC contactor (K3) is also connected to the discharge diode (D3).3.根据权利要求1或2所述的一种不间断电源内的镍氢电池充放电电路，其特征是，所述充电器包括整流桥（ZQ）、开关管（T3）、变压器（T）、整流二极管（D4）和PWM隔离驱动电路（U2），所述开关管（T3）与变压器（T）的原边线圈串联连接后接整流桥（ZQ）输出的直流电压，所述PWM隔离驱动电路（U2）的输入端接单片机（U1）的输出端口，其输出端接开关管（T3）的栅极；所述变压器（T）的副边线圈一端接充电器输出地，一端经整流二极管（D4）接充电继电器（K2）的公共触点。3. A Ni-MH battery charging and discharging circuit in an uninterruptible power supply according to claim 1 or 2, characterized in that the charger includes a rectifier bridge (ZQ), a switch tube (T3), and a transformer (T) , a rectifier diode (D4) and a PWM isolation drive circuit (U2), the switch tube (T3) is connected in series with the primary coil of the transformer (T) and then connected to the DC voltage output by the rectifier bridge (ZQ), and the PWM isolation drive The input terminal of the circuit (U2) is connected to the output port of the single-chip microcomputer (U1), and its output terminal is connected to the gate of the switch tube (T3); one end of the secondary coil of the transformer (T) is connected to the output ground of the charger, and the other end is passed through a rectifier diode (D4) Connect to the common contact of charging relay (K2).4.根据权利要求3所述的一种不间断电源内的镍氢电池充放电电路，其特征是， 所述充放电控制电路由DC/DC辅助电源供电，所述辅助电源的输入端接不间断电源直流升压（NB）的输入端。4. The Ni-MH battery charging and discharging circuit in a kind of uninterruptible power supply according to claim 3, it is characterized in that, said charging and discharging control circuit is powered by DC/DC auxiliary power supply, and the input terminal of said auxiliary power supply is not connected The input terminal of the DC boost (NB) of the intermittent power supply.5.根据权利要求4所述的一种不间断电源内的镍氢电池充放电电路，其特征是，所述充电继电器（K2）和放电继电器（K1）的控制线圈上均并接有续流二极管。5. The Ni-MH battery charging and discharging circuit in an uninterruptible power supply according to claim 4, characterized in that the control coils of the charging relay (K2) and the discharging relay (K1) are both connected in parallel with freewheeling diode.6.根据权利要求5所述的一种不间断电源内的镍氢电池充放电电路，其特征是，在镍氢电池（B）的放电回路中串接有熔断器（FU）。6. The Ni-MH battery charge-discharge circuit in an uninterruptible power supply according to claim 5, characterized in that a fuse (FU) is connected in series in the discharge circuit of the Ni-MH battery (B).

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