Type B EVSE MD Series Residual Current Monitoring Unit

1. Electric vehicles are developing rapidly, and the demand for charging piles is strong

The international standard "IEC62752-2016 (IC-CPD)" was officially released in 2016. The IC-CPD function and role are specified in the standard. Among them, TypeB residual current detection has become an important function. Residual current detection has also become a mode 2 charging cable and a standard accessory for charging piles. According to statistics, as of September 2019, there were 440,000 public charging piles in China, with an annual growth rate of 20%. The RCPD series residual current sensor launched by Shanghai Yiwen Electronic Technology Co., Ltd. (IVY) fully meets this standard. The second charging mode (Mode2) is gradually popularized. IC-CPD has become a standard accessory in electric vehicles. The popularity of IC-CPD can greatly facilitate charging at any time, including home charging and going out charging. As the second charging mode (Mode2), it is also accepted by more users. With the upgrade and unification of the standard, more OEMs will also choose IC-CPD as a standard accessory. 

2. The prevention of residual current of charging pile type B is more urgent

The residual current monitoring and the popular application of residual current can be traced back to around 1990. The earliest type is TypeAC, and so far, TypeB type residual current monitoring has been successively adopted in many fields. Its inclusion relationship is shown in Figure 2. It is precisely due to the complexity of electrical equipment and circuit topology that the residual current monitoring has been developed from TypeAC to the current TypeB. TypeB residual current definition includes TypeAC, TypeA and DC residual current, so TypeB residual current detection is a relatively high requirement for residual current detection at present. Type B refers to smooth DC and intermittent DC based on type A leakage (AC, jumping DC, half-wave AC). In order to ensure the safety of life and property, it is recommended to install a Type B leakage current sensor or a Type B leakage current circuit breaker with a higher protection level on the charging pile. There are two conventional means of preventing residual current:

1) Add Residual Current Circuit Breaker (RCD)

Leakage switches are commonly installed in household and industrial fields, such as TypeA leakage switches in gas water heaters, and leakage circuit breakers in industrial fields. Especially in the field of charging piles, since the standard stipulates that TypeA or TypeB leakage circuit breakers are required, the scheme of adding leakage circuit breakers in the circuit system is generally adopted. In 2018, many companies such as China Southern Power Grid also promoted B-type leakage current sensors in the field of charging piles.

2) Add Type B current sensor

For example, residual current sensors are commonly used in photovoltaic inverters for leakage protection. At present, this kind of scheme is widely used in IC-CPD.

IVY METERING Co., Ltd. (IVY METERING) has many years of experience in research and development of leakage current sensors, and has successively launched MD series leakage current sensors, MD0630T01A(PCB Mount), MD0630T41A(PCB&Cable Mount), MD0630T41A-1(Cable Mount), TypeB residual current sensor, small RCDs used in portable charger, Realize the AC and DC TypeB residual current detection function to meet the requirements of the new standard.